Vendored dependencies

Godeps/Godeps.json

@@ -0,0 +1,72 @@
+{
+	"ImportPath": "github.com/Luzifer/elb-instance-status",
+	"GoVersion": "go1.6",
+	"GodepVersion": "v62",
+	"Deps": [
+		{
+			"ImportPath": "bitbucket.org/ww/goautoneg",
+			"Comment": "null-5",
+			"Rev": "'75cd24fc2f2c2a2088577d12123ddee5f54e0675'"
+		},
+		{
+			"ImportPath": "github.com/Luzifer/rconfig",
+			"Comment": "v1.0.3-2-g2677653",
+			"Rev": "26776536e61487fdffbd3ce87f827177a5903f98"
+		},
+		{
+			"ImportPath": "github.com/beorn7/perks/quantile",
+			"Rev": "b965b613227fddccbfffe13eae360ed3fa822f8d"
+		},
+		{
+			"ImportPath": "github.com/golang/protobuf/proto",
+			"Rev": "8df8a93c670173cd1d8737a507a253b94f2d0b5a"
+		},
+		{
+			"ImportPath": "github.com/gorilla/context",
+			"Rev": "1c83b3eabd45b6d76072b66b746c20815fb2872d"
+		},
+		{
+			"ImportPath": "github.com/gorilla/mux",
+			"Rev": "49c024275504f0341e5a9971eb7ba7fa3dc7af40"
+		},
+		{
+			"ImportPath": "github.com/matttproud/golang_protobuf_extensions/pbutil",
+			"Rev": "fc2b8d3a73c4867e51861bbdd5ae3c1f0869dd6a"
+		},
+		{
+			"ImportPath": "github.com/prometheus/client_golang/prometheus",
+			"Comment": "0.7.0-39-g3b78d7a",
+			"Rev": "3b78d7a77f51ccbc364d4bc170920153022cfd08"
+		},
+		{
+			"ImportPath": "github.com/prometheus/client_model/go",
+			"Comment": "model-0.0.2-12-gfa8ad6f",
+			"Rev": "fa8ad6fec33561be4280a8f0514318c79d7f6cb6"
+		},
+		{
+			"ImportPath": "github.com/prometheus/common/expfmt",
+			"Rev": "ffd5d0f2976124c788687ec2ac194f5479e1f9c2"
+		},
+		{
+			"ImportPath": "github.com/prometheus/common/model",
+			"Rev": "ffd5d0f2976124c788687ec2ac194f5479e1f9c2"
+		},
+		{
+			"ImportPath": "github.com/prometheus/procfs",
+			"Rev": "3b231703e7dd0ca93302b5242ad6aeb4b5c603a2"
+		},
+		{
+			"ImportPath": "github.com/robfig/cron",
+			"Comment": "v1-2-g67823cd",
+			"Rev": "67823cd24dece1b04cced3a0a0b3ca2bc84d875e"
+		},
+		{
+			"ImportPath": "github.com/spf13/pflag",
+			"Rev": "b084184666e02084b8ccb9b704bf0d79c466eb1d"
+		},
+		{
+			"ImportPath": "gopkg.in/yaml.v2",
+			"Rev": "53feefa2559fb8dfa8d81baad31be332c97d6c77"
+		}
+	]
+}

Godeps/Readme

@@ -0,0 +1,5 @@
+This directory tree is generated automatically by godep.
+
+Please do not edit.
+
+See https://github.com/tools/godep for more information.

vendor/bitbucket.org/ww/goautoneg/Makefile

@@ -0,0 +1,13 @@
+include $(GOROOT)/src/Make.inc
+
+TARG=bitbucket.org/ww/goautoneg
+GOFILES=autoneg.go
+
+include $(GOROOT)/src/Make.pkg
+
+format:
+	gofmt -w *.go
+
+docs:
+	gomake clean
+	godoc ${TARG} > README.txt

vendor/bitbucket.org/ww/goautoneg/README.txt

@@ -0,0 +1,67 @@
+PACKAGE
+
+package goautoneg
+import "bitbucket.org/ww/goautoneg"
+
+HTTP Content-Type Autonegotiation.
+
+The functions in this package implement the behaviour specified in
+http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+
+Copyright (c) 2011, Open Knowledge Foundation Ltd.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    Neither the name of the Open Knowledge Foundation Ltd. nor the
+    names of its contributors may be used to endorse or promote
+    products derived from this software without specific prior written
+    permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+FUNCTIONS
+
+func Negotiate(header string, alternatives []string) (content_type string)
+Negotiate the most appropriate content_type given the accept header
+and a list of alternatives.
+
+func ParseAccept(header string) (accept []Accept)
+Parse an Accept Header string returning a sorted list
+of clauses
+
+
+TYPES
+
+type Accept struct {
+    Type, SubType string
+    Q             float32
+    Params        map[string]string
+}
+Structure to represent a clause in an HTTP Accept Header
+
+
+SUBDIRECTORIES
+
+	.hg

vendor/bitbucket.org/ww/goautoneg/autoneg.go

@@ -0,0 +1,162 @@
+/*
+HTTP Content-Type Autonegotiation.
+
+The functions in this package implement the behaviour specified in
+http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+
+Copyright (c) 2011, Open Knowledge Foundation Ltd.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    Neither the name of the Open Knowledge Foundation Ltd. nor the
+    names of its contributors may be used to endorse or promote
+    products derived from this software without specific prior written
+    permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+*/
+package goautoneg
+
+import (
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// Structure to represent a clause in an HTTP Accept Header
+type Accept struct {
+	Type, SubType string
+	Q             float64
+	Params        map[string]string
+}
+
+// For internal use, so that we can use the sort interface
+type accept_slice []Accept
+
+func (accept accept_slice) Len() int {
+	slice := []Accept(accept)
+	return len(slice)
+}
+
+func (accept accept_slice) Less(i, j int) bool {
+	slice := []Accept(accept)
+	ai, aj := slice[i], slice[j]
+	if ai.Q > aj.Q {
+		return true
+	}
+	if ai.Type != "*" && aj.Type == "*" {
+		return true
+	}
+	if ai.SubType != "*" && aj.SubType == "*" {
+		return true
+	}
+	return false
+}
+
+func (accept accept_slice) Swap(i, j int) {
+	slice := []Accept(accept)
+	slice[i], slice[j] = slice[j], slice[i]
+}
+
+// Parse an Accept Header string returning a sorted list
+// of clauses
+func ParseAccept(header string) (accept []Accept) {
+	parts := strings.Split(header, ",")
+	accept = make([]Accept, 0, len(parts))
+	for _, part := range parts {
+		part := strings.Trim(part, " ")
+
+		a := Accept{}
+		a.Params = make(map[string]string)
+		a.Q = 1.0
+
+		mrp := strings.Split(part, ";")
+
+		media_range := mrp[0]
+		sp := strings.Split(media_range, "/")
+		a.Type = strings.Trim(sp[0], " ")
+
+		switch {
+		case len(sp) == 1 && a.Type == "*":
+			a.SubType = "*"
+		case len(sp) == 2:
+			a.SubType = strings.Trim(sp[1], " ")
+		default:
+			continue
+		}
+
+		if len(mrp) == 1 {
+			accept = append(accept, a)
+			continue
+		}
+
+		for _, param := range mrp[1:] {
+			sp := strings.SplitN(param, "=", 2)
+			if len(sp) != 2 {
+				continue
+			}
+			token := strings.Trim(sp[0], " ")
+			if token == "q" {
+				a.Q, _ = strconv.ParseFloat(sp[1], 32)
+			} else {
+				a.Params[token] = strings.Trim(sp[1], " ")
+			}
+		}
+
+		accept = append(accept, a)
+	}
+
+	slice := accept_slice(accept)
+	sort.Sort(slice)
+
+	return
+}
+
+// Negotiate the most appropriate content_type given the accept header
+// and a list of alternatives.
+func Negotiate(header string, alternatives []string) (content_type string) {
+	asp := make([][]string, 0, len(alternatives))
+	for _, ctype := range alternatives {
+		asp = append(asp, strings.SplitN(ctype, "/", 2))
+	}
+	for _, clause := range ParseAccept(header) {
+		for i, ctsp := range asp {
+			if clause.Type == ctsp[0] && clause.SubType == ctsp[1] {
+				content_type = alternatives[i]
+				return
+			}
+			if clause.Type == ctsp[0] && clause.SubType == "*" {
+				content_type = alternatives[i]
+				return
+			}
+			if clause.Type == "*" && clause.SubType == "*" {
+				content_type = alternatives[i]
+				return
+			}
+		}
+	}
+	return
+}

vendor/github.com/Luzifer/rconfig/.travis.yml

@@ -0,0 +1,8 @@
+language: go
+
+go:
+  - 1.4
+  - 1.5
+  - tip
+
+script: go test -v -race -cover ./...

vendor/github.com/Luzifer/rconfig/LICENSE

@@ -0,0 +1,13 @@
+Copyright 2015 Knut Ahlers <knut@ahlers.me>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/github.com/Luzifer/rconfig/README.md

@@ -0,0 +1,94 @@
+[![Build Status](https://travis-ci.org/Luzifer/rconfig.svg?branch=master)](https://travis-ci.org/Luzifer/rconfig)
+[![License: Apache v2.0](https://badge.luzifer.io/v1/badge?color=5d79b5&title=license&text=Apache+v2.0)](http://www.apache.org/licenses/LICENSE-2.0)
+[![Documentation](https://badge.luzifer.io/v1/badge?title=godoc&text=reference)](https://godoc.org/github.com/Luzifer/rconfig)
+[![Go Report](http://goreportcard.com/badge/Luzifer/rconfig)](http://goreportcard.com/report/Luzifer/rconfig)
+
+## Description
+
+> Package rconfig implements a CLI configuration reader with struct-embedded defaults, environment variables and posix compatible flag parsing using the [pflag](https://github.com/spf13/pflag) library.
+
+## Installation
+
+Install by running:
+
+```
+go get -u github.com/Luzifer/rconfig
+```
+
+OR fetch a specific version:
+
+```
+go get -u gopkg.in/luzifer/rconfig.v1
+```
+
+Run tests by running:
+
+```
+go test -v -race -cover github.com/Luzifer/rconfig
+```
+
+## Usage
+
+As a first step define a struct holding your configuration:
+
+```go
+type config struct {
+  Username string `default:"unknown" flag:"user" description:"Your name"`
+  Details  struct {
+    Age int `default:"25" flag:"age" env:"age" description:"Your age"`
+  }
+}
+```
+
+Next create an instance of that struct and let `rconfig` fill that config:
+
+```go
+var cfg config
+func init() {
+  cfg = config{}
+  rconfig.Parse(&cfg)
+}
+```
+
+You're ready to access your configuration:
+
+```go
+func main() {
+  fmt.Printf("Hello %s, happy birthday for your %dth birthday.",
+		cfg.Username,
+		cfg.Details.Age)
+}
+```
+
+### Provide variable defaults by using a file
+
+Given you have a file `~/.myapp.yml` containing some secrets or usernames (for the example below username is assumed to be "luzifer") as a default configuration for your application you can use this source code to load the defaults from that file using the `vardefault` tag in your configuration struct.
+
+The order of the directives (lower number = higher precedence):
+
+1. Flags provided in command line
+1. Environment variables
+1. Variable defaults (`vardefault` tag in the struct)
+1. `default` tag in the struct
+
+```go
+type config struct {
+  Username string `vardefault:"username" flag:"username" description:"Your username"`
+}
+
+var cfg = config{}
+
+func init() {
+  rconfig.SetVariableDefaults(rconfig.VarDefaultsFromYAMLFile("~/.myapp.yml"))
+  rconfig.Parse(&cfg)
+}
+
+func main() {
+  fmt.Printf("Username = %s", cfg.Username)
+  // Output: Username = luzifer
+}
+```
+
+## More info
+
+You can see the full reference documentation of the rconfig package [at godoc.org](https://godoc.org/github.com/Luzifer/rconfig), or through go's standard documentation system by running `godoc -http=:6060` and browsing to [http://localhost:6060/pkg/github.com/Luzifer/rconfig](http://localhost:6060/pkg/github.com/Luzifer/rconfig) after installation.

vendor/github.com/Luzifer/rconfig/config.go

@@ -0,0 +1,314 @@
+// Package rconfig implements a CLI configuration reader with struct-embedded
+// defaults, environment variables and posix compatible flag parsing using
+// the pflag library.
+package rconfig
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"reflect"
+	"strconv"
+	"strings"
+
+	"github.com/spf13/pflag"
+)
+
+var (
+	fs               *pflag.FlagSet
+	variableDefaults map[string]string
+)
+
+func init() {
+	variableDefaults = make(map[string]string)
+}
+
+// Parse takes the pointer to a struct filled with variables which should be read
+// from ENV, default or flag. The precedence in this is flag > ENV > default. So
+// if a flag is specified on the CLI it will overwrite the ENV and otherwise ENV
+// overwrites the default specified.
+//
+// For your configuration struct you can use the following struct-tags to control
+// the behavior of rconfig:
+//
+//     default: Set a default value
+//     vardefault: Read the default value from the variable defaults
+//     env: Read the value from this environment variable
+//     flag: Flag to read in format "long,short" (for example "listen,l")
+//     description: A help text for Usage output to guide your users
+//
+// The format you need to specify those values you can see in the example to this
+// function.
+//
+func Parse(config interface{}) error {
+	return parse(config, nil)
+}
+
+// Args returns the non-flag command-line arguments.
+func Args() []string {
+	return fs.Args()
+}
+
+// Usage prints a basic usage with the corresponding defaults for the flags to
+// os.Stdout. The defaults are derived from the `default` struct-tag and the ENV.
+func Usage() {
+	if fs != nil && fs.Parsed() {
+		fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+		fs.PrintDefaults()
+	}
+}
+
+// SetVariableDefaults presets the parser with a map of default values to be used
+// when specifying the vardefault tag
+func SetVariableDefaults(defaults map[string]string) {
+	variableDefaults = defaults
+}
+
+func parse(in interface{}, args []string) error {
+	if args == nil {
+		args = os.Args
+	}
+
+	fs = pflag.NewFlagSet(os.Args[0], pflag.ExitOnError)
+	if err := execTags(in, fs); err != nil {
+		return err
+	}
+
+	return fs.Parse(args)
+}
+
+func execTags(in interface{}, fs *pflag.FlagSet) error {
+	if reflect.TypeOf(in).Kind() != reflect.Ptr {
+		return errors.New("Calling parser with non-pointer")
+	}
+
+	if reflect.ValueOf(in).Elem().Kind() != reflect.Struct {
+		return errors.New("Calling parser with pointer to non-struct")
+	}
+
+	st := reflect.ValueOf(in).Elem()
+	for i := 0; i < st.NumField(); i++ {
+		valField := st.Field(i)
+		typeField := st.Type().Field(i)
+
+		if typeField.Tag.Get("default") == "" && typeField.Tag.Get("env") == "" && typeField.Tag.Get("flag") == "" && typeField.Type.Kind() != reflect.Struct {
+			// None of our supported tags is present and it's not a sub-struct
+			continue
+		}
+
+		value := varDefault(typeField.Tag.Get("vardefault"), typeField.Tag.Get("default"))
+		value = envDefault(typeField.Tag.Get("env"), value)
+		parts := strings.Split(typeField.Tag.Get("flag"), ",")
+
+		switch typeField.Type.Kind() {
+		case reflect.String:
+			if typeField.Tag.Get("flag") != "" {
+				if len(parts) == 1 {
+					fs.StringVar(valField.Addr().Interface().(*string), parts[0], value, typeField.Tag.Get("description"))
+				} else {
+					fs.StringVarP(valField.Addr().Interface().(*string), parts[0], parts[1], value, typeField.Tag.Get("description"))
+				}
+			} else {
+				valField.SetString(value)
+			}
+
+		case reflect.Bool:
+			v := value == "true"
+			if typeField.Tag.Get("flag") != "" {
+				if len(parts) == 1 {
+					fs.BoolVar(valField.Addr().Interface().(*bool), parts[0], v, typeField.Tag.Get("description"))
+				} else {
+					fs.BoolVarP(valField.Addr().Interface().(*bool), parts[0], parts[1], v, typeField.Tag.Get("description"))
+				}
+			} else {
+				valField.SetBool(v)
+			}
+
+		case reflect.Int, reflect.Int8, reflect.Int32, reflect.Int64:
+			vt, err := strconv.ParseInt(value, 10, 64)
+			if err != nil {
+				if value == "" {
+					vt = 0
+				} else {
+					return err
+				}
+			}
+			if typeField.Tag.Get("flag") != "" {
+				registerFlagInt(typeField.Type.Kind(), fs, valField.Addr().Interface(), parts, vt, typeField.Tag.Get("description"))
+			} else {
+				valField.SetInt(vt)
+			}
+
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+			vt, err := strconv.ParseUint(value, 10, 64)
+			if err != nil {
+				if value == "" {
+					vt = 0
+				} else {
+					return err
+				}
+			}
+			if typeField.Tag.Get("flag") != "" {
+				registerFlagUint(typeField.Type.Kind(), fs, valField.Addr().Interface(), parts, vt, typeField.Tag.Get("description"))
+			} else {
+				valField.SetUint(vt)
+			}
+
+		case reflect.Float32, reflect.Float64:
+			vt, err := strconv.ParseFloat(value, 64)
+			if err != nil {
+				if value == "" {
+					vt = 0.0
+				} else {
+					return err
+				}
+			}
+			if typeField.Tag.Get("flag") != "" {
+				registerFlagFloat(typeField.Type.Kind(), fs, valField.Addr().Interface(), parts, vt, typeField.Tag.Get("description"))
+			} else {
+				valField.SetFloat(vt)
+			}
+
+		case reflect.Struct:
+			if err := execTags(valField.Addr().Interface(), fs); err != nil {
+				return err
+			}
+
+		case reflect.Slice:
+			switch typeField.Type.Elem().Kind() {
+			case reflect.Int:
+				def := []int{}
+				for _, v := range strings.Split(value, ",") {
+					it, err := strconv.ParseInt(strings.TrimSpace(v), 10, 64)
+					if err != nil {
+						return err
+					}
+					def = append(def, int(it))
+				}
+				if len(parts) == 1 {
+					fs.IntSliceVar(valField.Addr().Interface().(*[]int), parts[0], def, typeField.Tag.Get("description"))
+				} else {
+					fs.IntSliceVarP(valField.Addr().Interface().(*[]int), parts[0], parts[1], def, typeField.Tag.Get("description"))
+				}
+			case reflect.String:
+				del := typeField.Tag.Get("delimiter")
+				if len(del) == 0 {
+					del = ","
+				}
+				def := strings.Split(value, del)
+				if len(parts) == 1 {
+					fs.StringSliceVar(valField.Addr().Interface().(*[]string), parts[0], def, typeField.Tag.Get("description"))
+				} else {
+					fs.StringSliceVarP(valField.Addr().Interface().(*[]string), parts[0], parts[1], def, typeField.Tag.Get("description"))
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func registerFlagFloat(t reflect.Kind, fs *pflag.FlagSet, field interface{}, parts []string, vt float64, desc string) {
+	switch t {
+	case reflect.Float32:
+		if len(parts) == 1 {
+			fs.Float32Var(field.(*float32), parts[0], float32(vt), desc)
+		} else {
+			fs.Float32VarP(field.(*float32), parts[0], parts[1], float32(vt), desc)
+		}
+	case reflect.Float64:
+		if len(parts) == 1 {
+			fs.Float64Var(field.(*float64), parts[0], float64(vt), desc)
+		} else {
+			fs.Float64VarP(field.(*float64), parts[0], parts[1], float64(vt), desc)
+		}
+	}
+}
+
+func registerFlagInt(t reflect.Kind, fs *pflag.FlagSet, field interface{}, parts []string, vt int64, desc string) {
+	switch t {
+	case reflect.Int:
+		if len(parts) == 1 {
+			fs.IntVar(field.(*int), parts[0], int(vt), desc)
+		} else {
+			fs.IntVarP(field.(*int), parts[0], parts[1], int(vt), desc)
+		}
+	case reflect.Int8:
+		if len(parts) == 1 {
+			fs.Int8Var(field.(*int8), parts[0], int8(vt), desc)
+		} else {
+			fs.Int8VarP(field.(*int8), parts[0], parts[1], int8(vt), desc)
+		}
+	case reflect.Int32:
+		if len(parts) == 1 {
+			fs.Int32Var(field.(*int32), parts[0], int32(vt), desc)
+		} else {
+			fs.Int32VarP(field.(*int32), parts[0], parts[1], int32(vt), desc)
+		}
+	case reflect.Int64:
+		if len(parts) == 1 {
+			fs.Int64Var(field.(*int64), parts[0], int64(vt), desc)
+		} else {
+			fs.Int64VarP(field.(*int64), parts[0], parts[1], int64(vt), desc)
+		}
+	}
+}
+
+func registerFlagUint(t reflect.Kind, fs *pflag.FlagSet, field interface{}, parts []string, vt uint64, desc string) {
+	switch t {
+	case reflect.Uint:
+		if len(parts) == 1 {
+			fs.UintVar(field.(*uint), parts[0], uint(vt), desc)
+		} else {
+			fs.UintVarP(field.(*uint), parts[0], parts[1], uint(vt), desc)
+		}
+	case reflect.Uint8:
+		if len(parts) == 1 {
+			fs.Uint8Var(field.(*uint8), parts[0], uint8(vt), desc)
+		} else {
+			fs.Uint8VarP(field.(*uint8), parts[0], parts[1], uint8(vt), desc)
+		}
+	case reflect.Uint16:
+		if len(parts) == 1 {
+			fs.Uint16Var(field.(*uint16), parts[0], uint16(vt), desc)
+		} else {
+			fs.Uint16VarP(field.(*uint16), parts[0], parts[1], uint16(vt), desc)
+		}
+	case reflect.Uint32:
+		if len(parts) == 1 {
+			fs.Uint32Var(field.(*uint32), parts[0], uint32(vt), desc)
+		} else {
+			fs.Uint32VarP(field.(*uint32), parts[0], parts[1], uint32(vt), desc)
+		}
+	case reflect.Uint64:
+		if len(parts) == 1 {
+			fs.Uint64Var(field.(*uint64), parts[0], uint64(vt), desc)
+		} else {
+			fs.Uint64VarP(field.(*uint64), parts[0], parts[1], uint64(vt), desc)
+		}
+	}
+}
+
+func envDefault(env, def string) string {
+	value := def
+
+	if env != "" {
+		if e := os.Getenv(env); e != "" {
+			value = e
+		}
+	}
+
+	return value
+}
+
+func varDefault(name, def string) string {
+	value := def
+
+	if name != "" {
+		if v, ok := variableDefaults[name]; ok {
+			value = v
+		}
+	}
+
+	return value
+}

vendor/github.com/Luzifer/rconfig/vardefault_providers.go

@@ -0,0 +1,27 @@
+package rconfig
+
+import (
+	"io/ioutil"
+
+	"gopkg.in/yaml.v2"
+)
+
+// VarDefaultsFromYAMLFile reads contents of a file and calls VarDefaultsFromYAML
+func VarDefaultsFromYAMLFile(filename string) map[string]string {
+	data, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return make(map[string]string)
+	}
+
+	return VarDefaultsFromYAML(data)
+}
+
+// VarDefaultsFromYAML creates a vardefaults map from YAML raw data
+func VarDefaultsFromYAML(in []byte) map[string]string {
+	out := make(map[string]string)
+	err := yaml.Unmarshal(in, &out)
+	if err != nil {
+		return make(map[string]string)
+	}
+	return out
+}

vendor/github.com/beorn7/perks/quantile/stream.go

@@ -0,0 +1,292 @@
+// Package quantile computes approximate quantiles over an unbounded data
+// stream within low memory and CPU bounds.
+//
+// A small amount of accuracy is traded to achieve the above properties.
+//
+// Multiple streams can be merged before calling Query to generate a single set
+// of results. This is meaningful when the streams represent the same type of
+// data. See Merge and Samples.
+//
+// For more detailed information about the algorithm used, see:
+//
+// Effective Computation of Biased Quantiles over Data Streams
+//
+// http://www.cs.rutgers.edu/~muthu/bquant.pdf
+package quantile
+
+import (
+	"math"
+	"sort"
+)
+
+// Sample holds an observed value and meta information for compression. JSON
+// tags have been added for convenience.
+type Sample struct {
+	Value float64 `json:",string"`
+	Width float64 `json:",string"`
+	Delta float64 `json:",string"`
+}
+
+// Samples represents a slice of samples. It implements sort.Interface.
+type Samples []Sample
+
+func (a Samples) Len() int           { return len(a) }
+func (a Samples) Less(i, j int) bool { return a[i].Value < a[j].Value }
+func (a Samples) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+type invariant func(s *stream, r float64) float64
+
+// NewLowBiased returns an initialized Stream for low-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the lower ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within (1±Epsilon)*Quantile.
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewLowBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * r
+	}
+	return newStream(ƒ)
+}
+
+// NewHighBiased returns an initialized Stream for high-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the higher ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within 1-(1±Epsilon)*(1-Quantile).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewHighBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * (s.n - r)
+	}
+	return newStream(ƒ)
+}
+
+// NewTargeted returns an initialized Stream concerned with a particular set of
+// quantile values that are supplied a priori. Knowing these a priori reduces
+// space and computation time. The targets map maps the desired quantiles to
+// their absolute errors, i.e. the true quantile of a value returned by a query
+// is guaranteed to be within (Quantile±Epsilon).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error properties.
+func NewTargeted(targets map[float64]float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		var m = math.MaxFloat64
+		var f float64
+		for quantile, epsilon := range targets {
+			if quantile*s.n <= r {
+				f = (2 * epsilon * r) / quantile
+			} else {
+				f = (2 * epsilon * (s.n - r)) / (1 - quantile)
+			}
+			if f < m {
+				m = f
+			}
+		}
+		return m
+	}
+	return newStream(ƒ)
+}
+
+// Stream computes quantiles for a stream of float64s. It is not thread-safe by
+// design. Take care when using across multiple goroutines.
+type Stream struct {
+	*stream
+	b      Samples
+	sorted bool
+}
+
+func newStream(ƒ invariant) *Stream {
+	x := &stream{ƒ: ƒ}
+	return &Stream{x, make(Samples, 0, 500), true}
+}
+
+// Insert inserts v into the stream.
+func (s *Stream) Insert(v float64) {
+	s.insert(Sample{Value: v, Width: 1})
+}
+
+func (s *Stream) insert(sample Sample) {
+	s.b = append(s.b, sample)
+	s.sorted = false
+	if len(s.b) == cap(s.b) {
+		s.flush()
+	}
+}
+
+// Query returns the computed qth percentiles value. If s was created with
+// NewTargeted, and q is not in the set of quantiles provided a priori, Query
+// will return an unspecified result.
+func (s *Stream) Query(q float64) float64 {
+	if !s.flushed() {
+		// Fast path when there hasn't been enough data for a flush;
+		// this also yields better accuracy for small sets of data.
+		l := len(s.b)
+		if l == 0 {
+			return 0
+		}
+		i := int(float64(l) * q)
+		if i > 0 {
+			i -= 1
+		}
+		s.maybeSort()
+		return s.b[i].Value
+	}
+	s.flush()
+	return s.stream.query(q)
+}
+
+// Merge merges samples into the underlying streams samples. This is handy when
+// merging multiple streams from separate threads, database shards, etc.
+//
+// ATTENTION: This method is broken and does not yield correct results. The
+// underlying algorithm is not capable of merging streams correctly.
+func (s *Stream) Merge(samples Samples) {
+	sort.Sort(samples)
+	s.stream.merge(samples)
+}
+
+// Reset reinitializes and clears the list reusing the samples buffer memory.
+func (s *Stream) Reset() {
+	s.stream.reset()
+	s.b = s.b[:0]
+}
+
+// Samples returns stream samples held by s.
+func (s *Stream) Samples() Samples {
+	if !s.flushed() {
+		return s.b
+	}
+	s.flush()
+	return s.stream.samples()
+}
+
+// Count returns the total number of samples observed in the stream
+// since initialization.
+func (s *Stream) Count() int {
+	return len(s.b) + s.stream.count()
+}
+
+func (s *Stream) flush() {
+	s.maybeSort()
+	s.stream.merge(s.b)
+	s.b = s.b[:0]
+}
+
+func (s *Stream) maybeSort() {
+	if !s.sorted {
+		s.sorted = true
+		sort.Sort(s.b)
+	}
+}
+
+func (s *Stream) flushed() bool {
+	return len(s.stream.l) > 0
+}
+
+type stream struct {
+	n float64
+	l []Sample
+	ƒ invariant
+}
+
+func (s *stream) reset() {
+	s.l = s.l[:0]
+	s.n = 0
+}
+
+func (s *stream) insert(v float64) {
+	s.merge(Samples{{v, 1, 0}})
+}
+
+func (s *stream) merge(samples Samples) {
+	// TODO(beorn7): This tries to merge not only individual samples, but
+	// whole summaries. The paper doesn't mention merging summaries at
+	// all. Unittests show that the merging is inaccurate. Find out how to
+	// do merges properly.
+	var r float64
+	i := 0
+	for _, sample := range samples {
+		for ; i < len(s.l); i++ {
+			c := s.l[i]
+			if c.Value > sample.Value {
+				// Insert at position i.
+				s.l = append(s.l, Sample{})
+				copy(s.l[i+1:], s.l[i:])
+				s.l[i] = Sample{
+					sample.Value,
+					sample.Width,
+					math.Max(sample.Delta, math.Floor(s.ƒ(s, r))-1),
+					// TODO(beorn7): How to calculate delta correctly?
+				}
+				i++
+				goto inserted
+			}
+			r += c.Width
+		}
+		s.l = append(s.l, Sample{sample.Value, sample.Width, 0})
+		i++
+	inserted:
+		s.n += sample.Width
+		r += sample.Width
+	}
+	s.compress()
+}
+
+func (s *stream) count() int {
+	return int(s.n)
+}
+
+func (s *stream) query(q float64) float64 {
+	t := math.Ceil(q * s.n)
+	t += math.Ceil(s.ƒ(s, t) / 2)
+	p := s.l[0]
+	var r float64
+	for _, c := range s.l[1:] {
+		r += p.Width
+		if r+c.Width+c.Delta > t {
+			return p.Value
+		}
+		p = c
+	}
+	return p.Value
+}
+
+func (s *stream) compress() {
+	if len(s.l) < 2 {
+		return
+	}
+	x := s.l[len(s.l)-1]
+	xi := len(s.l) - 1
+	r := s.n - 1 - x.Width
+
+	for i := len(s.l) - 2; i >= 0; i-- {
+		c := s.l[i]
+		if c.Width+x.Width+x.Delta <= s.ƒ(s, r) {
+			x.Width += c.Width
+			s.l[xi] = x
+			// Remove element at i.
+			copy(s.l[i:], s.l[i+1:])
+			s.l = s.l[:len(s.l)-1]
+			xi -= 1
+		} else {
+			x = c
+			xi = i
+		}
+		r -= c.Width
+	}
+}
+
+func (s *stream) samples() Samples {
+	samples := make(Samples, len(s.l))
+	copy(samples, s.l)
+	return samples
+}

vendor/github.com/golang/protobuf/LICENSE

@@ -0,0 +1,31 @@
+Go support for Protocol Buffers - Google's data interchange format
+
+Copyright 2010 The Go Authors.  All rights reserved.
+https://github.com/golang/protobuf
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+

vendor/github.com/golang/protobuf/proto/Makefile

@@ -0,0 +1,43 @@
+# Go support for Protocol Buffers - Google's data interchange format
+#
+# Copyright 2010 The Go Authors.  All rights reserved.
+# https://github.com/golang/protobuf
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+install:
+	go install
+
+test: install generate-test-pbs
+	go test
+
+
+generate-test-pbs:
+	make install
+	make -C testdata
+	protoc --go_out=Mtestdata/test.proto=github.com/golang/protobuf/proto/testdata:. proto3_proto/proto3.proto
+	make

vendor/github.com/golang/protobuf/proto/clone.go

@@ -0,0 +1,223 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Protocol buffer deep copy and merge.
+// TODO: MessageSet and RawMessage.
+
+package proto
+
+import (
+	"log"
+	"reflect"
+	"strings"
+)
+
+// Clone returns a deep copy of a protocol buffer.
+func Clone(pb Message) Message {
+	in := reflect.ValueOf(pb)
+	if in.IsNil() {
+		return pb
+	}
+
+	out := reflect.New(in.Type().Elem())
+	// out is empty so a merge is a deep copy.
+	mergeStruct(out.Elem(), in.Elem())
+	return out.Interface().(Message)
+}
+
+// Merge merges src into dst.
+// Required and optional fields that are set in src will be set to that value in dst.
+// Elements of repeated fields will be appended.
+// Merge panics if src and dst are not the same type, or if dst is nil.
+func Merge(dst, src Message) {
+	in := reflect.ValueOf(src)
+	out := reflect.ValueOf(dst)
+	if out.IsNil() {
+		panic("proto: nil destination")
+	}
+	if in.Type() != out.Type() {
+		// Explicit test prior to mergeStruct so that mistyped nils will fail
+		panic("proto: type mismatch")
+	}
+	if in.IsNil() {
+		// Merging nil into non-nil is a quiet no-op
+		return
+	}
+	mergeStruct(out.Elem(), in.Elem())
+}
+
+func mergeStruct(out, in reflect.Value) {
+	sprop := GetProperties(in.Type())
+	for i := 0; i < in.NumField(); i++ {
+		f := in.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
+	}
+
+	if emIn, ok := in.Addr().Interface().(extendableProto); ok {
+		emOut := out.Addr().Interface().(extendableProto)
+		mergeExtension(emOut.ExtensionMap(), emIn.ExtensionMap())
+	}
+
+	uf := in.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return
+	}
+	uin := uf.Bytes()
+	if len(uin) > 0 {
+		out.FieldByName("XXX_unrecognized").SetBytes(append([]byte(nil), uin...))
+	}
+}
+
+// mergeAny performs a merge between two values of the same type.
+// viaPtr indicates whether the values were indirected through a pointer (implying proto2).
+// prop is set if this is a struct field (it may be nil).
+func mergeAny(out, in reflect.Value, viaPtr bool, prop *Properties) {
+	if in.Type() == protoMessageType {
+		if !in.IsNil() {
+			if out.IsNil() {
+				out.Set(reflect.ValueOf(Clone(in.Interface().(Message))))
+			} else {
+				Merge(out.Interface().(Message), in.Interface().(Message))
+			}
+		}
+		return
+	}
+	switch in.Kind() {
+	case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+		reflect.String, reflect.Uint32, reflect.Uint64:
+		if !viaPtr && isProto3Zero(in) {
+			return
+		}
+		out.Set(in)
+	case reflect.Interface:
+		// Probably a oneof field; copy non-nil values.
+		if in.IsNil() {
+			return
+		}
+		// Allocate destination if it is not set, or set to a different type.
+		// Otherwise we will merge as normal.
+		if out.IsNil() || out.Elem().Type() != in.Elem().Type() {
+			out.Set(reflect.New(in.Elem().Elem().Type())) // interface -> *T -> T -> new(T)
+		}
+		mergeAny(out.Elem(), in.Elem(), false, nil)
+	case reflect.Map:
+		if in.Len() == 0 {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.MakeMap(in.Type()))
+		}
+		// For maps with value types of *T or []byte we need to deep copy each value.
+		elemKind := in.Type().Elem().Kind()
+		for _, key := range in.MapKeys() {
+			var val reflect.Value
+			switch elemKind {
+			case reflect.Ptr:
+				val = reflect.New(in.Type().Elem().Elem())
+				mergeAny(val, in.MapIndex(key), false, nil)
+			case reflect.Slice:
+				val = in.MapIndex(key)
+				val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
+			default:
+				val = in.MapIndex(key)
+			}
+			out.SetMapIndex(key, val)
+		}
+	case reflect.Ptr:
+		if in.IsNil() {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.New(in.Elem().Type()))
+		}
+		mergeAny(out.Elem(), in.Elem(), true, nil)
+	case reflect.Slice:
+		if in.IsNil() {
+			return
+		}
+		if in.Type().Elem().Kind() == reflect.Uint8 {
+			// []byte is a scalar bytes field, not a repeated field.
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value, and should not
+			// be merged.
+			if prop != nil && prop.proto3 && in.Len() == 0 {
+				return
+			}
+
+			// Make a deep copy.
+			// Append to []byte{} instead of []byte(nil) so that we never end up
+			// with a nil result.
+			out.SetBytes(append([]byte{}, in.Bytes()...))
+			return
+		}
+		n := in.Len()
+		if out.IsNil() {
+			out.Set(reflect.MakeSlice(in.Type(), 0, n))
+		}
+		switch in.Type().Elem().Kind() {
+		case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+			reflect.String, reflect.Uint32, reflect.Uint64:
+			out.Set(reflect.AppendSlice(out, in))
+		default:
+			for i := 0; i < n; i++ {
+				x := reflect.Indirect(reflect.New(in.Type().Elem()))
+				mergeAny(x, in.Index(i), false, nil)
+				out.Set(reflect.Append(out, x))
+			}
+		}
+	case reflect.Struct:
+		mergeStruct(out, in)
+	default:
+		// unknown type, so not a protocol buffer
+		log.Printf("proto: don't know how to copy %v", in)
+	}
+}
+
+func mergeExtension(out, in map[int32]Extension) {
+	for extNum, eIn := range in {
+		eOut := Extension{desc: eIn.desc}
+		if eIn.value != nil {
+			v := reflect.New(reflect.TypeOf(eIn.value)).Elem()
+			mergeAny(v, reflect.ValueOf(eIn.value), false, nil)
+			eOut.value = v.Interface()
+		}
+		if eIn.enc != nil {
+			eOut.enc = make([]byte, len(eIn.enc))
+			copy(eOut.enc, eIn.enc)
+		}
+
+		out[extNum] = eOut
+	}
+}

vendor/github.com/golang/protobuf/proto/decode.go

@@ -0,0 +1,863 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for decoding protocol buffer data to construct in-memory representations.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+)
+
+// errOverflow is returned when an integer is too large to be represented.
+var errOverflow = errors.New("proto: integer overflow")
+
+// ErrInternalBadWireType is returned by generated code when an incorrect
+// wire type is encountered. It does not get returned to user code.
+var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for oneof")
+
+// The fundamental decoders that interpret bytes on the wire.
+// Those that take integer types all return uint64 and are
+// therefore of type valueDecoder.
+
+// DecodeVarint reads a varint-encoded integer from the slice.
+// It returns the integer and the number of bytes consumed, or
+// zero if there is not enough.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func DecodeVarint(buf []byte) (x uint64, n int) {
+	// x, n already 0
+	for shift := uint(0); shift < 64; shift += 7 {
+		if n >= len(buf) {
+			return 0, 0
+		}
+		b := uint64(buf[n])
+		n++
+		x |= (b & 0x7F) << shift
+		if (b & 0x80) == 0 {
+			return x, n
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	return 0, 0
+}
+
+// DecodeVarint reads a varint-encoded integer from the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) DecodeVarint() (x uint64, err error) {
+	// x, err already 0
+
+	i := p.index
+	l := len(p.buf)
+
+	for shift := uint(0); shift < 64; shift += 7 {
+		if i >= l {
+			err = io.ErrUnexpectedEOF
+			return
+		}
+		b := p.buf[i]
+		i++
+		x |= (uint64(b) & 0x7F) << shift
+		if b < 0x80 {
+			p.index = i
+			return
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	err = errOverflow
+	return
+}
+
+// DecodeFixed64 reads a 64-bit integer from the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) DecodeFixed64() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 8
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-8])
+	x |= uint64(p.buf[i-7]) << 8
+	x |= uint64(p.buf[i-6]) << 16
+	x |= uint64(p.buf[i-5]) << 24
+	x |= uint64(p.buf[i-4]) << 32
+	x |= uint64(p.buf[i-3]) << 40
+	x |= uint64(p.buf[i-2]) << 48
+	x |= uint64(p.buf[i-1]) << 56
+	return
+}
+
+// DecodeFixed32 reads a 32-bit integer from the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) DecodeFixed32() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 4
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-4])
+	x |= uint64(p.buf[i-3]) << 8
+	x |= uint64(p.buf[i-2]) << 16
+	x |= uint64(p.buf[i-1]) << 24
+	return
+}
+
+// DecodeZigzag64 reads a zigzag-encoded 64-bit integer
+// from the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) DecodeZigzag64() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = (x >> 1) ^ uint64((int64(x&1)<<63)>>63)
+	return
+}
+
+// DecodeZigzag32 reads a zigzag-encoded 32-bit integer
+// from  the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) DecodeZigzag32() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = uint64((uint32(x) >> 1) ^ uint32((int32(x&1)<<31)>>31))
+	return
+}
+
+// These are not ValueDecoders: they produce an array of bytes or a string.
+// bytes, embedded messages
+
+// DecodeRawBytes reads a count-delimited byte buffer from the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) DecodeRawBytes(alloc bool) (buf []byte, err error) {
+	n, err := p.DecodeVarint()
+	if err != nil {
+		return nil, err
+	}
+
+	nb := int(n)
+	if nb < 0 {
+		return nil, fmt.Errorf("proto: bad byte length %d", nb)
+	}
+	end := p.index + nb
+	if end < p.index || end > len(p.buf) {
+		return nil, io.ErrUnexpectedEOF
+	}
+
+	if !alloc {
+		// todo: check if can get more uses of alloc=false
+		buf = p.buf[p.index:end]
+		p.index += nb
+		return
+	}
+
+	buf = make([]byte, nb)
+	copy(buf, p.buf[p.index:])
+	p.index += nb
+	return
+}
+
+// DecodeStringBytes reads an encoded string from the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) DecodeStringBytes() (s string, err error) {
+	buf, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return
+	}
+	return string(buf), nil
+}
+
+// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
+// If the protocol buffer has extensions, and the field matches, add it as an extension.
+// Otherwise, if the XXX_unrecognized field exists, append the skipped data there.
+func (o *Buffer) skipAndSave(t reflect.Type, tag, wire int, base structPointer, unrecField field) error {
+	oi := o.index
+
+	err := o.skip(t, tag, wire)
+	if err != nil {
+		return err
+	}
+
+	if !unrecField.IsValid() {
+		return nil
+	}
+
+	ptr := structPointer_Bytes(base, unrecField)
+
+	// Add the skipped field to struct field
+	obuf := o.buf
+
+	o.buf = *ptr
+	o.EncodeVarint(uint64(tag<<3 | wire))
+	*ptr = append(o.buf, obuf[oi:o.index]...)
+
+	o.buf = obuf
+
+	return nil
+}
+
+// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
+func (o *Buffer) skip(t reflect.Type, tag, wire int) error {
+
+	var u uint64
+	var err error
+
+	switch wire {
+	case WireVarint:
+		_, err = o.DecodeVarint()
+	case WireFixed64:
+		_, err = o.DecodeFixed64()
+	case WireBytes:
+		_, err = o.DecodeRawBytes(false)
+	case WireFixed32:
+		_, err = o.DecodeFixed32()
+	case WireStartGroup:
+		for {
+			u, err = o.DecodeVarint()
+			if err != nil {
+				break
+			}
+			fwire := int(u & 0x7)
+			if fwire == WireEndGroup {
+				break
+			}
+			ftag := int(u >> 3)
+			err = o.skip(t, ftag, fwire)
+			if err != nil {
+				break
+			}
+		}
+	default:
+		err = fmt.Errorf("proto: can't skip unknown wire type %d for %s", wire, t)
+	}
+	return err
+}
+
+// Unmarshaler is the interface representing objects that can
+// unmarshal themselves.  The method should reset the receiver before
+// decoding starts.  The argument points to data that may be
+// overwritten, so implementations should not keep references to the
+// buffer.
+type Unmarshaler interface {
+	Unmarshal([]byte) error
+}
+
+// Unmarshal parses the protocol buffer representation in buf and places the
+// decoded result in pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// Unmarshal resets pb before starting to unmarshal, so any
+// existing data in pb is always removed. Use UnmarshalMerge
+// to preserve and append to existing data.
+func Unmarshal(buf []byte, pb Message) error {
+	pb.Reset()
+	return UnmarshalMerge(buf, pb)
+}
+
+// UnmarshalMerge parses the protocol buffer representation in buf and
+// writes the decoded result to pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// UnmarshalMerge merges into existing data in pb.
+// Most code should use Unmarshal instead.
+func UnmarshalMerge(buf []byte, pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(Unmarshaler); ok {
+		return u.Unmarshal(buf)
+	}
+	return NewBuffer(buf).Unmarshal(pb)
+}
+
+// DecodeMessage reads a count-delimited message from the Buffer.
+func (p *Buffer) DecodeMessage(pb Message) error {
+	enc, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	return NewBuffer(enc).Unmarshal(pb)
+}
+
+// DecodeGroup reads a tag-delimited group from the Buffer.
+func (p *Buffer) DecodeGroup(pb Message) error {
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+	return p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), true, base)
+}
+
+// Unmarshal parses the protocol buffer representation in the
+// Buffer and places the decoded result in pb.  If the struct
+// underlying pb does not match the data in the buffer, the results can be
+// unpredictable.
+func (p *Buffer) Unmarshal(pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(Unmarshaler); ok {
+		err := u.Unmarshal(p.buf[p.index:])
+		p.index = len(p.buf)
+		return err
+	}
+
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+
+	err = p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), false, base)
+
+	if collectStats {
+		stats.Decode++
+	}
+
+	return err
+}
+
+// unmarshalType does the work of unmarshaling a structure.
+func (o *Buffer) unmarshalType(st reflect.Type, prop *StructProperties, is_group bool, base structPointer) error {
+	var state errorState
+	required, reqFields := prop.reqCount, uint64(0)
+
+	var err error
+	for err == nil && o.index < len(o.buf) {
+		oi := o.index
+		var u uint64
+		u, err = o.DecodeVarint()
+		if err != nil {
+			break
+		}
+		wire := int(u & 0x7)
+		if wire == WireEndGroup {
+			if is_group {
+				return nil // input is satisfied
+			}
+			return fmt.Errorf("proto: %s: wiretype end group for non-group", st)
+		}
+		tag := int(u >> 3)
+		if tag <= 0 {
+			return fmt.Errorf("proto: %s: illegal tag %d (wire type %d)", st, tag, wire)
+		}
+		fieldnum, ok := prop.decoderTags.get(tag)
+		if !ok {
+			// Maybe it's an extension?
+			if prop.extendable {
+				if e := structPointer_Interface(base, st).(extendableProto); isExtensionField(e, int32(tag)) {
+					if err = o.skip(st, tag, wire); err == nil {
+						ext := e.ExtensionMap()[int32(tag)] // may be missing
+						ext.enc = append(ext.enc, o.buf[oi:o.index]...)
+						e.ExtensionMap()[int32(tag)] = ext
+					}
+					continue
+				}
+			}
+			// Maybe it's a oneof?
+			if prop.oneofUnmarshaler != nil {
+				m := structPointer_Interface(base, st).(Message)
+				// First return value indicates whether tag is a oneof field.
+				ok, err = prop.oneofUnmarshaler(m, tag, wire, o)
+				if err == ErrInternalBadWireType {
+					// Map the error to something more descriptive.
+					// Do the formatting here to save generated code space.
+					err = fmt.Errorf("bad wiretype for oneof field in %T", m)
+				}
+				if ok {
+					continue
+				}
+			}
+			err = o.skipAndSave(st, tag, wire, base, prop.unrecField)
+			continue
+		}
+		p := prop.Prop[fieldnum]
+
+		if p.dec == nil {
+			fmt.Fprintf(os.Stderr, "proto: no protobuf decoder for %s.%s\n", st, st.Field(fieldnum).Name)
+			continue
+		}
+		dec := p.dec
+		if wire != WireStartGroup && wire != p.WireType {
+			if wire == WireBytes && p.packedDec != nil {
+				// a packable field
+				dec = p.packedDec
+			} else {
+				err = fmt.Errorf("proto: bad wiretype for field %s.%s: got wiretype %d, want %d", st, st.Field(fieldnum).Name, wire, p.WireType)
+				continue
+			}
+		}
+		decErr := dec(o, p, base)
+		if decErr != nil && !state.shouldContinue(decErr, p) {
+			err = decErr
+		}
+		if err == nil && p.Required {
+			// Successfully decoded a required field.
+			if tag <= 64 {
+				// use bitmap for fields 1-64 to catch field reuse.
+				var mask uint64 = 1 << uint64(tag-1)
+				if reqFields&mask == 0 {
+					// new required field
+					reqFields |= mask
+					required--
+				}
+			} else {
+				// This is imprecise. It can be fooled by a required field
+				// with a tag > 64 that is encoded twice; that's very rare.
+				// A fully correct implementation would require allocating
+				// a data structure, which we would like to avoid.
+				required--
+			}
+		}
+	}
+	if err == nil {
+		if is_group {
+			return io.ErrUnexpectedEOF
+		}
+		if state.err != nil {
+			return state.err
+		}
+		if required > 0 {
+			// Not enough information to determine the exact field. If we use extra
+			// CPU, we could determine the field only if the missing required field
+			// has a tag <= 64 and we check reqFields.
+			return &RequiredNotSetError{"{Unknown}"}
+		}
+	}
+	return err
+}
+
+// Individual type decoders
+// For each,
+//	u is the decoded value,
+//	v is a pointer to the field (pointer) in the struct
+
+// Sizes of the pools to allocate inside the Buffer.
+// The goal is modest amortization and allocation
+// on at least 16-byte boundaries.
+const (
+	boolPoolSize   = 16
+	uint32PoolSize = 8
+	uint64PoolSize = 4
+)
+
+// Decode a bool.
+func (o *Buffer) dec_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	if len(o.bools) == 0 {
+		o.bools = make([]bool, boolPoolSize)
+	}
+	o.bools[0] = u != 0
+	*structPointer_Bool(base, p.field) = &o.bools[0]
+	o.bools = o.bools[1:]
+	return nil
+}
+
+func (o *Buffer) dec_proto3_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	*structPointer_BoolVal(base, p.field) = u != 0
+	return nil
+}
+
+// Decode an int32.
+func (o *Buffer) dec_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word32_Set(structPointer_Word32(base, p.field), o, uint32(u))
+	return nil
+}
+
+func (o *Buffer) dec_proto3_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word32Val_Set(structPointer_Word32Val(base, p.field), uint32(u))
+	return nil
+}
+
+// Decode an int64.
+func (o *Buffer) dec_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word64_Set(structPointer_Word64(base, p.field), o, u)
+	return nil
+}
+
+func (o *Buffer) dec_proto3_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word64Val_Set(structPointer_Word64Val(base, p.field), o, u)
+	return nil
+}
+
+// Decode a string.
+func (o *Buffer) dec_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	*structPointer_String(base, p.field) = &s
+	return nil
+}
+
+func (o *Buffer) dec_proto3_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	*structPointer_StringVal(base, p.field) = s
+	return nil
+}
+
+// Decode a slice of bytes ([]byte).
+func (o *Buffer) dec_slice_byte(p *Properties, base structPointer) error {
+	b, err := o.DecodeRawBytes(true)
+	if err != nil {
+		return err
+	}
+	*structPointer_Bytes(base, p.field) = b
+	return nil
+}
+
+// Decode a slice of bools ([]bool).
+func (o *Buffer) dec_slice_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	v := structPointer_BoolSlice(base, p.field)
+	*v = append(*v, u != 0)
+	return nil
+}
+
+// Decode a slice of bools ([]bool) in packed format.
+func (o *Buffer) dec_slice_packed_bool(p *Properties, base structPointer) error {
+	v := structPointer_BoolSlice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded bools
+
+	y := *v
+	for i := 0; i < nb; i++ {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		y = append(y, u != 0)
+	}
+
+	*v = y
+	return nil
+}
+
+// Decode a slice of int32s ([]int32).
+func (o *Buffer) dec_slice_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	structPointer_Word32Slice(base, p.field).Append(uint32(u))
+	return nil
+}
+
+// Decode a slice of int32s ([]int32) in packed format.
+func (o *Buffer) dec_slice_packed_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Slice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded int32s
+
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		v.Append(uint32(u))
+	}
+	return nil
+}
+
+// Decode a slice of int64s ([]int64).
+func (o *Buffer) dec_slice_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+
+	structPointer_Word64Slice(base, p.field).Append(u)
+	return nil
+}
+
+// Decode a slice of int64s ([]int64) in packed format.
+func (o *Buffer) dec_slice_packed_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64Slice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded int64s
+
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		v.Append(u)
+	}
+	return nil
+}
+
+// Decode a slice of strings ([]string).
+func (o *Buffer) dec_slice_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	v := structPointer_StringSlice(base, p.field)
+	*v = append(*v, s)
+	return nil
+}
+
+// Decode a slice of slice of bytes ([][]byte).
+func (o *Buffer) dec_slice_slice_byte(p *Properties, base structPointer) error {
+	b, err := o.DecodeRawBytes(true)
+	if err != nil {
+		return err
+	}
+	v := structPointer_BytesSlice(base, p.field)
+	*v = append(*v, b)
+	return nil
+}
+
+// Decode a map field.
+func (o *Buffer) dec_new_map(p *Properties, base structPointer) error {
+	raw, err := o.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	oi := o.index       // index at the end of this map entry
+	o.index -= len(raw) // move buffer back to start of map entry
+
+	mptr := structPointer_NewAt(base, p.field, p.mtype) // *map[K]V
+	if mptr.Elem().IsNil() {
+		mptr.Elem().Set(reflect.MakeMap(mptr.Type().Elem()))
+	}
+	v := mptr.Elem() // map[K]V
+
+	// Prepare addressable doubly-indirect placeholders for the key and value types.
+	// See enc_new_map for why.
+	keyptr := reflect.New(reflect.PtrTo(p.mtype.Key())).Elem() // addressable *K
+	keybase := toStructPointer(keyptr.Addr())                  // **K
+
+	var valbase structPointer
+	var valptr reflect.Value
+	switch p.mtype.Elem().Kind() {
+	case reflect.Slice:
+		// []byte
+		var dummy []byte
+		valptr = reflect.ValueOf(&dummy)  // *[]byte
+		valbase = toStructPointer(valptr) // *[]byte
+	case reflect.Ptr:
+		// message; valptr is **Msg; need to allocate the intermediate pointer
+		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
+		valptr.Set(reflect.New(valptr.Type().Elem()))
+		valbase = toStructPointer(valptr)
+	default:
+		// everything else
+		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
+		valbase = toStructPointer(valptr.Addr())                   // **V
+	}
+
+	// Decode.
+	// This parses a restricted wire format, namely the encoding of a message
+	// with two fields. See enc_new_map for the format.
+	for o.index < oi {
+		// tagcode for key and value properties are always a single byte
+		// because they have tags 1 and 2.
+		tagcode := o.buf[o.index]
+		o.index++
+		switch tagcode {
+		case p.mkeyprop.tagcode[0]:
+			if err := p.mkeyprop.dec(o, p.mkeyprop, keybase); err != nil {
+				return err
+			}
+		case p.mvalprop.tagcode[0]:
+			if err := p.mvalprop.dec(o, p.mvalprop, valbase); err != nil {
+				return err
+			}
+		default:
+			// TODO: Should we silently skip this instead?
+			return fmt.Errorf("proto: bad map data tag %d", raw[0])
+		}
+	}
+	keyelem, valelem := keyptr.Elem(), valptr.Elem()
+	if !keyelem.IsValid() || !valelem.IsValid() {
+		// We did not decode the key or the value in the map entry.
+		// Either way, it's an invalid map entry.
+		return fmt.Errorf("proto: bad map data: missing key/val")
+	}
+
+	v.SetMapIndex(keyelem, valelem)
+	return nil
+}
+
+// Decode a group.
+func (o *Buffer) dec_struct_group(p *Properties, base structPointer) error {
+	bas := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(bas) {
+		// allocate new nested message
+		bas = toStructPointer(reflect.New(p.stype))
+		structPointer_SetStructPointer(base, p.field, bas)
+	}
+	return o.unmarshalType(p.stype, p.sprop, true, bas)
+}
+
+// Decode an embedded message.
+func (o *Buffer) dec_struct_message(p *Properties, base structPointer) (err error) {
+	raw, e := o.DecodeRawBytes(false)
+	if e != nil {
+		return e
+	}
+
+	bas := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(bas) {
+		// allocate new nested message
+		bas = toStructPointer(reflect.New(p.stype))
+		structPointer_SetStructPointer(base, p.field, bas)
+	}
+
+	// If the object can unmarshal itself, let it.
+	if p.isUnmarshaler {
+		iv := structPointer_Interface(bas, p.stype)
+		return iv.(Unmarshaler).Unmarshal(raw)
+	}
+
+	obuf := o.buf
+	oi := o.index
+	o.buf = raw
+	o.index = 0
+
+	err = o.unmarshalType(p.stype, p.sprop, false, bas)
+	o.buf = obuf
+	o.index = oi
+
+	return err
+}
+
+// Decode a slice of embedded messages.
+func (o *Buffer) dec_slice_struct_message(p *Properties, base structPointer) error {
+	return o.dec_slice_struct(p, false, base)
+}
+
+// Decode a slice of embedded groups.
+func (o *Buffer) dec_slice_struct_group(p *Properties, base structPointer) error {
+	return o.dec_slice_struct(p, true, base)
+}
+
+// Decode a slice of structs ([]*struct).
+func (o *Buffer) dec_slice_struct(p *Properties, is_group bool, base structPointer) error {
+	v := reflect.New(p.stype)
+	bas := toStructPointer(v)
+	structPointer_StructPointerSlice(base, p.field).Append(bas)
+
+	if is_group {
+		err := o.unmarshalType(p.stype, p.sprop, is_group, bas)
+		return err
+	}
+
+	raw, err := o.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+
+	// If the object can unmarshal itself, let it.
+	if p.isUnmarshaler {
+		iv := v.Interface()
+		return iv.(Unmarshaler).Unmarshal(raw)
+	}
+
+	obuf := o.buf
+	oi := o.index
+	o.buf = raw
+	o.index = 0
+
+	err = o.unmarshalType(p.stype, p.sprop, is_group, bas)
+
+	o.buf = obuf
+	o.index = oi
+
+	return err
+}

vendor/github.com/golang/protobuf/proto/equal.go

@@ -0,0 +1,267 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Protocol buffer comparison.
+// TODO: MessageSet.
+
+package proto
+
+import (
+	"bytes"
+	"log"
+	"reflect"
+	"strings"
+)
+
+/*
+Equal returns true iff protocol buffers a and b are equal.
+The arguments must both be pointers to protocol buffer structs.
+
+Equality is defined in this way:
+  - Two messages are equal iff they are the same type,
+    corresponding fields are equal, unknown field sets
+    are equal, and extensions sets are equal.
+  - Two set scalar fields are equal iff their values are equal.
+    If the fields are of a floating-point type, remember that
+    NaN != x for all x, including NaN.
+  - Two repeated fields are equal iff their lengths are the same,
+    and their corresponding elements are equal (a "bytes" field,
+    although represented by []byte, is not a repeated field)
+  - Two unset fields are equal.
+  - Two unknown field sets are equal if their current
+    encoded state is equal.
+  - Two extension sets are equal iff they have corresponding
+    elements that are pairwise equal.
+  - Every other combination of things are not equal.
+
+The return value is undefined if a and b are not protocol buffers.
+*/
+func Equal(a, b Message) bool {
+	if a == nil || b == nil {
+		return a == b
+	}
+	v1, v2 := reflect.ValueOf(a), reflect.ValueOf(b)
+	if v1.Type() != v2.Type() {
+		return false
+	}
+	if v1.Kind() == reflect.Ptr {
+		if v1.IsNil() {
+			return v2.IsNil()
+		}
+		if v2.IsNil() {
+			return false
+		}
+		v1, v2 = v1.Elem(), v2.Elem()
+	}
+	if v1.Kind() != reflect.Struct {
+		return false
+	}
+	return equalStruct(v1, v2)
+}
+
+// v1 and v2 are known to have the same type.
+func equalStruct(v1, v2 reflect.Value) bool {
+	for i := 0; i < v1.NumField(); i++ {
+		f := v1.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		f1, f2 := v1.Field(i), v2.Field(i)
+		if f.Type.Kind() == reflect.Ptr {
+			if n1, n2 := f1.IsNil(), f2.IsNil(); n1 && n2 {
+				// both unset
+				continue
+			} else if n1 != n2 {
+				// set/unset mismatch
+				return false
+			}
+			b1, ok := f1.Interface().(raw)
+			if ok {
+				b2 := f2.Interface().(raw)
+				// RawMessage
+				if !bytes.Equal(b1.Bytes(), b2.Bytes()) {
+					return false
+				}
+				continue
+			}
+			f1, f2 = f1.Elem(), f2.Elem()
+		}
+		if !equalAny(f1, f2) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_extensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_extensions")
+		if !equalExtensions(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
+			return false
+		}
+	}
+
+	uf := v1.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return true
+	}
+
+	u1 := uf.Bytes()
+	u2 := v2.FieldByName("XXX_unrecognized").Bytes()
+	if !bytes.Equal(u1, u2) {
+		return false
+	}
+
+	return true
+}
+
+// v1 and v2 are known to have the same type.
+func equalAny(v1, v2 reflect.Value) bool {
+	if v1.Type() == protoMessageType {
+		m1, _ := v1.Interface().(Message)
+		m2, _ := v2.Interface().(Message)
+		return Equal(m1, m2)
+	}
+	switch v1.Kind() {
+	case reflect.Bool:
+		return v1.Bool() == v2.Bool()
+	case reflect.Float32, reflect.Float64:
+		return v1.Float() == v2.Float()
+	case reflect.Int32, reflect.Int64:
+		return v1.Int() == v2.Int()
+	case reflect.Interface:
+		// Probably a oneof field; compare the inner values.
+		n1, n2 := v1.IsNil(), v2.IsNil()
+		if n1 || n2 {
+			return n1 == n2
+		}
+		e1, e2 := v1.Elem(), v2.Elem()
+		if e1.Type() != e2.Type() {
+			return false
+		}
+		return equalAny(e1, e2)
+	case reflect.Map:
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for _, key := range v1.MapKeys() {
+			val2 := v2.MapIndex(key)
+			if !val2.IsValid() {
+				// This key was not found in the second map.
+				return false
+			}
+			if !equalAny(v1.MapIndex(key), val2) {
+				return false
+			}
+		}
+		return true
+	case reflect.Ptr:
+		return equalAny(v1.Elem(), v2.Elem())
+	case reflect.Slice:
+		if v1.Type().Elem().Kind() == reflect.Uint8 {
+			// short circuit: []byte
+			if v1.IsNil() != v2.IsNil() {
+				return false
+			}
+			return bytes.Equal(v1.Interface().([]byte), v2.Interface().([]byte))
+		}
+
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for i := 0; i < v1.Len(); i++ {
+			if !equalAny(v1.Index(i), v2.Index(i)) {
+				return false
+			}
+		}
+		return true
+	case reflect.String:
+		return v1.Interface().(string) == v2.Interface().(string)
+	case reflect.Struct:
+		return equalStruct(v1, v2)
+	case reflect.Uint32, reflect.Uint64:
+		return v1.Uint() == v2.Uint()
+	}
+
+	// unknown type, so not a protocol buffer
+	log.Printf("proto: don't know how to compare %v", v1)
+	return false
+}
+
+// base is the struct type that the extensions are based on.
+// em1 and em2 are extension maps.
+func equalExtensions(base reflect.Type, em1, em2 map[int32]Extension) bool {
+	if len(em1) != len(em2) {
+		return false
+	}
+
+	for extNum, e1 := range em1 {
+		e2, ok := em2[extNum]
+		if !ok {
+			return false
+		}
+
+		m1, m2 := e1.value, e2.value
+
+		if m1 != nil && m2 != nil {
+			// Both are unencoded.
+			if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2)) {
+				return false
+			}
+			continue
+		}
+
+		// At least one is encoded. To do a semantically correct comparison
+		// we need to unmarshal them first.
+		var desc *ExtensionDesc
+		if m := extensionMaps[base]; m != nil {
+			desc = m[extNum]
+		}
+		if desc == nil {
+			log.Printf("proto: don't know how to compare extension %d of %v", extNum, base)
+			continue
+		}
+		var err error
+		if m1 == nil {
+			m1, err = decodeExtension(e1.enc, desc)
+		}
+		if m2 == nil && err == nil {
+			m2, err = decodeExtension(e2.enc, desc)
+		}
+		if err != nil {
+			// The encoded form is invalid.
+			log.Printf("proto: badly encoded extension %d of %v: %v", extNum, base, err)
+			return false
+		}
+		if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2)) {
+			return false
+		}
+	}
+
+	return true
+}

vendor/github.com/golang/protobuf/proto/extensions.go

@@ -0,0 +1,400 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Types and routines for supporting protocol buffer extensions.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"sync"
+)
+
+// ErrMissingExtension is the error returned by GetExtension if the named extension is not in the message.
+var ErrMissingExtension = errors.New("proto: missing extension")
+
+// ExtensionRange represents a range of message extensions for a protocol buffer.
+// Used in code generated by the protocol compiler.
+type ExtensionRange struct {
+	Start, End int32 // both inclusive
+}
+
+// extendableProto is an interface implemented by any protocol buffer that may be extended.
+type extendableProto interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	ExtensionMap() map[int32]Extension
+}
+
+var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem()
+
+// ExtensionDesc represents an extension specification.
+// Used in generated code from the protocol compiler.
+type ExtensionDesc struct {
+	ExtendedType  Message     // nil pointer to the type that is being extended
+	ExtensionType interface{} // nil pointer to the extension type
+	Field         int32       // field number
+	Name          string      // fully-qualified name of extension, for text formatting
+	Tag           string      // protobuf tag style
+}
+
+func (ed *ExtensionDesc) repeated() bool {
+	t := reflect.TypeOf(ed.ExtensionType)
+	return t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8
+}
+
+// Extension represents an extension in a message.
+type Extension struct {
+	// When an extension is stored in a message using SetExtension
+	// only desc and value are set. When the message is marshaled
+	// enc will be set to the encoded form of the message.
+	//
+	// When a message is unmarshaled and contains extensions, each
+	// extension will have only enc set. When such an extension is
+	// accessed using GetExtension (or GetExtensions) desc and value
+	// will be set.
+	desc  *ExtensionDesc
+	value interface{}
+	enc   []byte
+}
+
+// SetRawExtension is for testing only.
+func SetRawExtension(base extendableProto, id int32, b []byte) {
+	base.ExtensionMap()[id] = Extension{enc: b}
+}
+
+// isExtensionField returns true iff the given field number is in an extension range.
+func isExtensionField(pb extendableProto, field int32) bool {
+	for _, er := range pb.ExtensionRangeArray() {
+		if er.Start <= field && field <= er.End {
+			return true
+		}
+	}
+	return false
+}
+
+// checkExtensionTypes checks that the given extension is valid for pb.
+func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error {
+	// Check the extended type.
+	if a, b := reflect.TypeOf(pb), reflect.TypeOf(extension.ExtendedType); a != b {
+		return errors.New("proto: bad extended type; " + b.String() + " does not extend " + a.String())
+	}
+	// Check the range.
+	if !isExtensionField(pb, extension.Field) {
+		return errors.New("proto: bad extension number; not in declared ranges")
+	}
+	return nil
+}
+
+// extPropKey is sufficient to uniquely identify an extension.
+type extPropKey struct {
+	base  reflect.Type
+	field int32
+}
+
+var extProp = struct {
+	sync.RWMutex
+	m map[extPropKey]*Properties
+}{
+	m: make(map[extPropKey]*Properties),
+}
+
+func extensionProperties(ed *ExtensionDesc) *Properties {
+	key := extPropKey{base: reflect.TypeOf(ed.ExtendedType), field: ed.Field}
+
+	extProp.RLock()
+	if prop, ok := extProp.m[key]; ok {
+		extProp.RUnlock()
+		return prop
+	}
+	extProp.RUnlock()
+
+	extProp.Lock()
+	defer extProp.Unlock()
+	// Check again.
+	if prop, ok := extProp.m[key]; ok {
+		return prop
+	}
+
+	prop := new(Properties)
+	prop.Init(reflect.TypeOf(ed.ExtensionType), "unknown_name", ed.Tag, nil)
+	extProp.m[key] = prop
+	return prop
+}
+
+// encodeExtensionMap encodes any unmarshaled (unencoded) extensions in m.
+func encodeExtensionMap(m map[int32]Extension) error {
+	for k, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		p := NewBuffer(nil)
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		if err := props.enc(p, props, toStructPointer(x)); err != nil {
+			return err
+		}
+		e.enc = p.buf
+		m[k] = e
+	}
+	return nil
+}
+
+func sizeExtensionMap(m map[int32]Extension) (n int) {
+	for _, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			n += len(e.enc)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		n += props.size(props, toStructPointer(x))
+	}
+	return
+}
+
+// HasExtension returns whether the given extension is present in pb.
+func HasExtension(pb extendableProto, extension *ExtensionDesc) bool {
+	// TODO: Check types, field numbers, etc.?
+	_, ok := pb.ExtensionMap()[extension.Field]
+	return ok
+}
+
+// ClearExtension removes the given extension from pb.
+func ClearExtension(pb extendableProto, extension *ExtensionDesc) {
+	// TODO: Check types, field numbers, etc.?
+	delete(pb.ExtensionMap(), extension.Field)
+}
+
+// GetExtension parses and returns the given extension of pb.
+// If the extension is not present and has no default value it returns ErrMissingExtension.
+func GetExtension(pb extendableProto, extension *ExtensionDesc) (interface{}, error) {
+	if err := checkExtensionTypes(pb, extension); err != nil {
+		return nil, err
+	}
+
+	emap := pb.ExtensionMap()
+	e, ok := emap[extension.Field]
+	if !ok {
+		// defaultExtensionValue returns the default value or
+		// ErrMissingExtension if there is no default.
+		return defaultExtensionValue(extension)
+	}
+
+	if e.value != nil {
+		// Already decoded. Check the descriptor, though.
+		if e.desc != extension {
+			// This shouldn't happen. If it does, it means that
+			// GetExtension was called twice with two different
+			// descriptors with the same field number.
+			return nil, errors.New("proto: descriptor conflict")
+		}
+		return e.value, nil
+	}
+
+	v, err := decodeExtension(e.enc, extension)
+	if err != nil {
+		return nil, err
+	}
+
+	// Remember the decoded version and drop the encoded version.
+	// That way it is safe to mutate what we return.
+	e.value = v
+	e.desc = extension
+	e.enc = nil
+	emap[extension.Field] = e
+	return e.value, nil
+}
+
+// defaultExtensionValue returns the default value for extension.
+// If no default for an extension is defined ErrMissingExtension is returned.
+func defaultExtensionValue(extension *ExtensionDesc) (interface{}, error) {
+	t := reflect.TypeOf(extension.ExtensionType)
+	props := extensionProperties(extension)
+
+	sf, _, err := fieldDefault(t, props)
+	if err != nil {
+		return nil, err
+	}
+
+	if sf == nil || sf.value == nil {
+		// There is no default value.
+		return nil, ErrMissingExtension
+	}
+
+	if t.Kind() != reflect.Ptr {
+		// We do not need to return a Ptr, we can directly return sf.value.
+		return sf.value, nil
+	}
+
+	// We need to return an interface{} that is a pointer to sf.value.
+	value := reflect.New(t).Elem()
+	value.Set(reflect.New(value.Type().Elem()))
+	if sf.kind == reflect.Int32 {
+		// We may have an int32 or an enum, but the underlying data is int32.
+		// Since we can't set an int32 into a non int32 reflect.value directly
+		// set it as a int32.
+		value.Elem().SetInt(int64(sf.value.(int32)))
+	} else {
+		value.Elem().Set(reflect.ValueOf(sf.value))
+	}
+	return value.Interface(), nil
+}
+
+// decodeExtension decodes an extension encoded in b.
+func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
+	o := NewBuffer(b)
+
+	t := reflect.TypeOf(extension.ExtensionType)
+	rep := extension.repeated()
+
+	props := extensionProperties(extension)
+
+	// t is a pointer to a struct, pointer to basic type or a slice.
+	// Allocate a "field" to store the pointer/slice itself; the
+	// pointer/slice will be stored here. We pass
+	// the address of this field to props.dec.
+	// This passes a zero field and a *t and lets props.dec
+	// interpret it as a *struct{ x t }.
+	value := reflect.New(t).Elem()
+
+	for {
+		// Discard wire type and field number varint. It isn't needed.
+		if _, err := o.DecodeVarint(); err != nil {
+			return nil, err
+		}
+
+		if err := props.dec(o, props, toStructPointer(value.Addr())); err != nil {
+			return nil, err
+		}
+
+		if !rep || o.index >= len(o.buf) {
+			break
+		}
+	}
+	return value.Interface(), nil
+}
+
+// GetExtensions returns a slice of the extensions present in pb that are also listed in es.
+// The returned slice has the same length as es; missing extensions will appear as nil elements.
+func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) {
+	epb, ok := pb.(extendableProto)
+	if !ok {
+		err = errors.New("proto: not an extendable proto")
+		return
+	}
+	extensions = make([]interface{}, len(es))
+	for i, e := range es {
+		extensions[i], err = GetExtension(epb, e)
+		if err == ErrMissingExtension {
+			err = nil
+		}
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// SetExtension sets the specified extension of pb to the specified value.
+func SetExtension(pb extendableProto, extension *ExtensionDesc, value interface{}) error {
+	if err := checkExtensionTypes(pb, extension); err != nil {
+		return err
+	}
+	typ := reflect.TypeOf(extension.ExtensionType)
+	if typ != reflect.TypeOf(value) {
+		return errors.New("proto: bad extension value type")
+	}
+	// nil extension values need to be caught early, because the
+	// encoder can't distinguish an ErrNil due to a nil extension
+	// from an ErrNil due to a missing field. Extensions are
+	// always optional, so the encoder would just swallow the error
+	// and drop all the extensions from the encoded message.
+	if reflect.ValueOf(value).IsNil() {
+		return fmt.Errorf("proto: SetExtension called with nil value of type %T", value)
+	}
+
+	pb.ExtensionMap()[extension.Field] = Extension{desc: extension, value: value}
+	return nil
+}
+
+// A global registry of extensions.
+// The generated code will register the generated descriptors by calling RegisterExtension.
+
+var extensionMaps = make(map[reflect.Type]map[int32]*ExtensionDesc)
+
+// RegisterExtension is called from the generated code.
+func RegisterExtension(desc *ExtensionDesc) {
+	st := reflect.TypeOf(desc.ExtendedType).Elem()
+	m := extensionMaps[st]
+	if m == nil {
+		m = make(map[int32]*ExtensionDesc)
+		extensionMaps[st] = m
+	}
+	if _, ok := m[desc.Field]; ok {
+		panic("proto: duplicate extension registered: " + st.String() + " " + strconv.Itoa(int(desc.Field)))
+	}
+	m[desc.Field] = desc
+}
+
+// RegisteredExtensions returns a map of the registered extensions of a
+// protocol buffer struct, indexed by the extension number.
+// The argument pb should be a nil pointer to the struct type.
+func RegisteredExtensions(pb Message) map[int32]*ExtensionDesc {
+	return extensionMaps[reflect.TypeOf(pb).Elem()]
+}

vendor/github.com/golang/protobuf/proto/lib.go

@@ -0,0 +1,883 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/*
+Package proto converts data structures to and from the wire format of
+protocol buffers.  It works in concert with the Go source code generated
+for .proto files by the protocol compiler.
+
+A summary of the properties of the protocol buffer interface
+for a protocol buffer variable v:
+
+  - Names are turned from camel_case to CamelCase for export.
+  - There are no methods on v to set fields; just treat
+	them as structure fields.
+  - There are getters that return a field's value if set,
+	and return the field's default value if unset.
+	The getters work even if the receiver is a nil message.
+  - The zero value for a struct is its correct initialization state.
+	All desired fields must be set before marshaling.
+  - A Reset() method will restore a protobuf struct to its zero state.
+  - Non-repeated fields are pointers to the values; nil means unset.
+	That is, optional or required field int32 f becomes F *int32.
+  - Repeated fields are slices.
+  - Helper functions are available to aid the setting of fields.
+	msg.Foo = proto.String("hello") // set field
+  - Constants are defined to hold the default values of all fields that
+	have them.  They have the form Default_StructName_FieldName.
+	Because the getter methods handle defaulted values,
+	direct use of these constants should be rare.
+  - Enums are given type names and maps from names to values.
+	Enum values are prefixed by the enclosing message's name, or by the
+	enum's type name if it is a top-level enum. Enum types have a String
+	method, and a Enum method to assist in message construction.
+  - Nested messages, groups and enums have type names prefixed with the name of
+	the surrounding message type.
+  - Extensions are given descriptor names that start with E_,
+	followed by an underscore-delimited list of the nested messages
+	that contain it (if any) followed by the CamelCased name of the
+	extension field itself.  HasExtension, ClearExtension, GetExtension
+	and SetExtension are functions for manipulating extensions.
+  - Oneof field sets are given a single field in their message,
+	with distinguished wrapper types for each possible field value.
+  - Marshal and Unmarshal are functions to encode and decode the wire format.
+
+The simplest way to describe this is to see an example.
+Given file test.proto, containing
+
+	package example;
+
+	enum FOO { X = 17; }
+
+	message Test {
+	  required string label = 1;
+	  optional int32 type = 2 [default=77];
+	  repeated int64 reps = 3;
+	  optional group OptionalGroup = 4 {
+	    required string RequiredField = 5;
+	  }
+	  oneof union {
+	    int32 number = 6;
+	    string name = 7;
+	  }
+	}
+
+The resulting file, test.pb.go, is:
+
+	package example
+
+	import proto "github.com/golang/protobuf/proto"
+	import math "math"
+
+	type FOO int32
+	const (
+		FOO_X FOO = 17
+	)
+	var FOO_name = map[int32]string{
+		17: "X",
+	}
+	var FOO_value = map[string]int32{
+		"X": 17,
+	}
+
+	func (x FOO) Enum() *FOO {
+		p := new(FOO)
+		*p = x
+		return p
+	}
+	func (x FOO) String() string {
+		return proto.EnumName(FOO_name, int32(x))
+	}
+	func (x *FOO) UnmarshalJSON(data []byte) error {
+		value, err := proto.UnmarshalJSONEnum(FOO_value, data)
+		if err != nil {
+			return err
+		}
+		*x = FOO(value)
+		return nil
+	}
+
+	type Test struct {
+		Label         *string             `protobuf:"bytes,1,req,name=label" json:"label,omitempty"`
+		Type          *int32              `protobuf:"varint,2,opt,name=type,def=77" json:"type,omitempty"`
+		Reps          []int64             `protobuf:"varint,3,rep,name=reps" json:"reps,omitempty"`
+		Optionalgroup *Test_OptionalGroup `protobuf:"group,4,opt,name=OptionalGroup" json:"optionalgroup,omitempty"`
+		// Types that are valid to be assigned to Union:
+		//	*Test_Number
+		//	*Test_Name
+		Union            isTest_Union `protobuf_oneof:"union"`
+		XXX_unrecognized []byte       `json:"-"`
+	}
+	func (m *Test) Reset()         { *m = Test{} }
+	func (m *Test) String() string { return proto.CompactTextString(m) }
+	func (*Test) ProtoMessage() {}
+
+	type isTest_Union interface {
+		isTest_Union()
+	}
+
+	type Test_Number struct {
+		Number int32 `protobuf:"varint,6,opt,name=number"`
+	}
+	type Test_Name struct {
+		Name string `protobuf:"bytes,7,opt,name=name"`
+	}
+
+	func (*Test_Number) isTest_Union() {}
+	func (*Test_Name) isTest_Union()   {}
+
+	func (m *Test) GetUnion() isTest_Union {
+		if m != nil {
+			return m.Union
+		}
+		return nil
+	}
+	const Default_Test_Type int32 = 77
+
+	func (m *Test) GetLabel() string {
+		if m != nil && m.Label != nil {
+			return *m.Label
+		}
+		return ""
+	}
+
+	func (m *Test) GetType() int32 {
+		if m != nil && m.Type != nil {
+			return *m.Type
+		}
+		return Default_Test_Type
+	}
+
+	func (m *Test) GetOptionalgroup() *Test_OptionalGroup {
+		if m != nil {
+			return m.Optionalgroup
+		}
+		return nil
+	}
+
+	type Test_OptionalGroup struct {
+		RequiredField *string `protobuf:"bytes,5,req" json:"RequiredField,omitempty"`
+	}
+	func (m *Test_OptionalGroup) Reset()         { *m = Test_OptionalGroup{} }
+	func (m *Test_OptionalGroup) String() string { return proto.CompactTextString(m) }
+
+	func (m *Test_OptionalGroup) GetRequiredField() string {
+		if m != nil && m.RequiredField != nil {
+			return *m.RequiredField
+		}
+		return ""
+	}
+
+	func (m *Test) GetNumber() int32 {
+		if x, ok := m.GetUnion().(*Test_Number); ok {
+			return x.Number
+		}
+		return 0
+	}
+
+	func (m *Test) GetName() string {
+		if x, ok := m.GetUnion().(*Test_Name); ok {
+			return x.Name
+		}
+		return ""
+	}
+
+	func init() {
+		proto.RegisterEnum("example.FOO", FOO_name, FOO_value)
+	}
+
+To create and play with a Test object:
+
+package main
+
+	import (
+		"log"
+
+		"github.com/golang/protobuf/proto"
+		pb "./example.pb"
+	)
+
+	func main() {
+		test := &pb.Test{
+			Label: proto.String("hello"),
+			Type:  proto.Int32(17),
+			Optionalgroup: &pb.Test_OptionalGroup{
+				RequiredField: proto.String("good bye"),
+			},
+			Union: &pb.Test_Name{"fred"},
+		}
+		data, err := proto.Marshal(test)
+		if err != nil {
+			log.Fatal("marshaling error: ", err)
+		}
+		newTest := &pb.Test{}
+		err = proto.Unmarshal(data, newTest)
+		if err != nil {
+			log.Fatal("unmarshaling error: ", err)
+		}
+		// Now test and newTest contain the same data.
+		if test.GetLabel() != newTest.GetLabel() {
+			log.Fatalf("data mismatch %q != %q", test.GetLabel(), newTest.GetLabel())
+		}
+		// Use a type switch to determine which oneof was set.
+		switch u := test.Union.(type) {
+		case *pb.Test_Number: // u.Number contains the number.
+		case *pb.Test_Name: // u.Name contains the string.
+		}
+		// etc.
+	}
+*/
+package proto
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"reflect"
+	"sort"
+	"strconv"
+	"sync"
+)
+
+// Message is implemented by generated protocol buffer messages.
+type Message interface {
+	Reset()
+	String() string
+	ProtoMessage()
+}
+
+// Stats records allocation details about the protocol buffer encoders
+// and decoders.  Useful for tuning the library itself.
+type Stats struct {
+	Emalloc uint64 // mallocs in encode
+	Dmalloc uint64 // mallocs in decode
+	Encode  uint64 // number of encodes
+	Decode  uint64 // number of decodes
+	Chit    uint64 // number of cache hits
+	Cmiss   uint64 // number of cache misses
+	Size    uint64 // number of sizes
+}
+
+// Set to true to enable stats collection.
+const collectStats = false
+
+var stats Stats
+
+// GetStats returns a copy of the global Stats structure.
+func GetStats() Stats { return stats }
+
+// A Buffer is a buffer manager for marshaling and unmarshaling
+// protocol buffers.  It may be reused between invocations to
+// reduce memory usage.  It is not necessary to use a Buffer;
+// the global functions Marshal and Unmarshal create a
+// temporary Buffer and are fine for most applications.
+type Buffer struct {
+	buf   []byte // encode/decode byte stream
+	index int    // write point
+
+	// pools of basic types to amortize allocation.
+	bools   []bool
+	uint32s []uint32
+	uint64s []uint64
+
+	// extra pools, only used with pointer_reflect.go
+	int32s   []int32
+	int64s   []int64
+	float32s []float32
+	float64s []float64
+}
+
+// NewBuffer allocates a new Buffer and initializes its internal data to
+// the contents of the argument slice.
+func NewBuffer(e []byte) *Buffer {
+	return &Buffer{buf: e}
+}
+
+// Reset resets the Buffer, ready for marshaling a new protocol buffer.
+func (p *Buffer) Reset() {
+	p.buf = p.buf[0:0] // for reading/writing
+	p.index = 0        // for reading
+}
+
+// SetBuf replaces the internal buffer with the slice,
+// ready for unmarshaling the contents of the slice.
+func (p *Buffer) SetBuf(s []byte) {
+	p.buf = s
+	p.index = 0
+}
+
+// Bytes returns the contents of the Buffer.
+func (p *Buffer) Bytes() []byte { return p.buf }
+
+/*
+ * Helper routines for simplifying the creation of optional fields of basic type.
+ */
+
+// Bool is a helper routine that allocates a new bool value
+// to store v and returns a pointer to it.
+func Bool(v bool) *bool {
+	return &v
+}
+
+// Int32 is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it.
+func Int32(v int32) *int32 {
+	return &v
+}
+
+// Int is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it, but unlike Int32
+// its argument value is an int.
+func Int(v int) *int32 {
+	p := new(int32)
+	*p = int32(v)
+	return p
+}
+
+// Int64 is a helper routine that allocates a new int64 value
+// to store v and returns a pointer to it.
+func Int64(v int64) *int64 {
+	return &v
+}
+
+// Float32 is a helper routine that allocates a new float32 value
+// to store v and returns a pointer to it.
+func Float32(v float32) *float32 {
+	return &v
+}
+
+// Float64 is a helper routine that allocates a new float64 value
+// to store v and returns a pointer to it.
+func Float64(v float64) *float64 {
+	return &v
+}
+
+// Uint32 is a helper routine that allocates a new uint32 value
+// to store v and returns a pointer to it.
+func Uint32(v uint32) *uint32 {
+	return &v
+}
+
+// Uint64 is a helper routine that allocates a new uint64 value
+// to store v and returns a pointer to it.
+func Uint64(v uint64) *uint64 {
+	return &v
+}
+
+// String is a helper routine that allocates a new string value
+// to store v and returns a pointer to it.
+func String(v string) *string {
+	return &v
+}
+
+// EnumName is a helper function to simplify printing protocol buffer enums
+// by name.  Given an enum map and a value, it returns a useful string.
+func EnumName(m map[int32]string, v int32) string {
+	s, ok := m[v]
+	if ok {
+		return s
+	}
+	return strconv.Itoa(int(v))
+}
+
+// UnmarshalJSONEnum is a helper function to simplify recovering enum int values
+// from their JSON-encoded representation. Given a map from the enum's symbolic
+// names to its int values, and a byte buffer containing the JSON-encoded
+// value, it returns an int32 that can be cast to the enum type by the caller.
+//
+// The function can deal with both JSON representations, numeric and symbolic.
+func UnmarshalJSONEnum(m map[string]int32, data []byte, enumName string) (int32, error) {
+	if data[0] == '"' {
+		// New style: enums are strings.
+		var repr string
+		if err := json.Unmarshal(data, &repr); err != nil {
+			return -1, err
+		}
+		val, ok := m[repr]
+		if !ok {
+			return 0, fmt.Errorf("unrecognized enum %s value %q", enumName, repr)
+		}
+		return val, nil
+	}
+	// Old style: enums are ints.
+	var val int32
+	if err := json.Unmarshal(data, &val); err != nil {
+		return 0, fmt.Errorf("cannot unmarshal %#q into enum %s", data, enumName)
+	}
+	return val, nil
+}
+
+// DebugPrint dumps the encoded data in b in a debugging format with a header
+// including the string s. Used in testing but made available for general debugging.
+func (p *Buffer) DebugPrint(s string, b []byte) {
+	var u uint64
+
+	obuf := p.buf
+	index := p.index
+	p.buf = b
+	p.index = 0
+	depth := 0
+
+	fmt.Printf("\n--- %s ---\n", s)
+
+out:
+	for {
+		for i := 0; i < depth; i++ {
+			fmt.Print("  ")
+		}
+
+		index := p.index
+		if index == len(p.buf) {
+			break
+		}
+
+		op, err := p.DecodeVarint()
+		if err != nil {
+			fmt.Printf("%3d: fetching op err %v\n", index, err)
+			break out
+		}
+		tag := op >> 3
+		wire := op & 7
+
+		switch wire {
+		default:
+			fmt.Printf("%3d: t=%3d unknown wire=%d\n",
+				index, tag, wire)
+			break out
+
+		case WireBytes:
+			var r []byte
+
+			r, err = p.DecodeRawBytes(false)
+			if err != nil {
+				break out
+			}
+			fmt.Printf("%3d: t=%3d bytes [%d]", index, tag, len(r))
+			if len(r) <= 6 {
+				for i := 0; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			} else {
+				for i := 0; i < 3; i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+				fmt.Printf(" ..")
+				for i := len(r) - 3; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			}
+			fmt.Printf("\n")
+
+		case WireFixed32:
+			u, err = p.DecodeFixed32()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix32 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix32 %d\n", index, tag, u)
+
+		case WireFixed64:
+			u, err = p.DecodeFixed64()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix64 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix64 %d\n", index, tag, u)
+
+		case WireVarint:
+			u, err = p.DecodeVarint()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d varint err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d varint %d\n", index, tag, u)
+
+		case WireStartGroup:
+			fmt.Printf("%3d: t=%3d start\n", index, tag)
+			depth++
+
+		case WireEndGroup:
+			depth--
+			fmt.Printf("%3d: t=%3d end\n", index, tag)
+		}
+	}
+
+	if depth != 0 {
+		fmt.Printf("%3d: start-end not balanced %d\n", p.index, depth)
+	}
+	fmt.Printf("\n")
+
+	p.buf = obuf
+	p.index = index
+}
+
+// SetDefaults sets unset protocol buffer fields to their default values.
+// It only modifies fields that are both unset and have defined defaults.
+// It recursively sets default values in any non-nil sub-messages.
+func SetDefaults(pb Message) {
+	setDefaults(reflect.ValueOf(pb), true, false)
+}
+
+// v is a pointer to a struct.
+func setDefaults(v reflect.Value, recur, zeros bool) {
+	v = v.Elem()
+
+	defaultMu.RLock()
+	dm, ok := defaults[v.Type()]
+	defaultMu.RUnlock()
+	if !ok {
+		dm = buildDefaultMessage(v.Type())
+		defaultMu.Lock()
+		defaults[v.Type()] = dm
+		defaultMu.Unlock()
+	}
+
+	for _, sf := range dm.scalars {
+		f := v.Field(sf.index)
+		if !f.IsNil() {
+			// field already set
+			continue
+		}
+		dv := sf.value
+		if dv == nil && !zeros {
+			// no explicit default, and don't want to set zeros
+			continue
+		}
+		fptr := f.Addr().Interface() // **T
+		// TODO: Consider batching the allocations we do here.
+		switch sf.kind {
+		case reflect.Bool:
+			b := new(bool)
+			if dv != nil {
+				*b = dv.(bool)
+			}
+			*(fptr.(**bool)) = b
+		case reflect.Float32:
+			f := new(float32)
+			if dv != nil {
+				*f = dv.(float32)
+			}
+			*(fptr.(**float32)) = f
+		case reflect.Float64:
+			f := new(float64)
+			if dv != nil {
+				*f = dv.(float64)
+			}
+			*(fptr.(**float64)) = f
+		case reflect.Int32:
+			// might be an enum
+			if ft := f.Type(); ft != int32PtrType {
+				// enum
+				f.Set(reflect.New(ft.Elem()))
+				if dv != nil {
+					f.Elem().SetInt(int64(dv.(int32)))
+				}
+			} else {
+				// int32 field
+				i := new(int32)
+				if dv != nil {
+					*i = dv.(int32)
+				}
+				*(fptr.(**int32)) = i
+			}
+		case reflect.Int64:
+			i := new(int64)
+			if dv != nil {
+				*i = dv.(int64)
+			}
+			*(fptr.(**int64)) = i
+		case reflect.String:
+			s := new(string)
+			if dv != nil {
+				*s = dv.(string)
+			}
+			*(fptr.(**string)) = s
+		case reflect.Uint8:
+			// exceptional case: []byte
+			var b []byte
+			if dv != nil {
+				db := dv.([]byte)
+				b = make([]byte, len(db))
+				copy(b, db)
+			} else {
+				b = []byte{}
+			}
+			*(fptr.(*[]byte)) = b
+		case reflect.Uint32:
+			u := new(uint32)
+			if dv != nil {
+				*u = dv.(uint32)
+			}
+			*(fptr.(**uint32)) = u
+		case reflect.Uint64:
+			u := new(uint64)
+			if dv != nil {
+				*u = dv.(uint64)
+			}
+			*(fptr.(**uint64)) = u
+		default:
+			log.Printf("proto: can't set default for field %v (sf.kind=%v)", f, sf.kind)
+		}
+	}
+
+	for _, ni := range dm.nested {
+		f := v.Field(ni)
+		// f is *T or []*T or map[T]*T
+		switch f.Kind() {
+		case reflect.Ptr:
+			if f.IsNil() {
+				continue
+			}
+			setDefaults(f, recur, zeros)
+
+		case reflect.Slice:
+			for i := 0; i < f.Len(); i++ {
+				e := f.Index(i)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+
+		case reflect.Map:
+			for _, k := range f.MapKeys() {
+				e := f.MapIndex(k)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+		}
+	}
+}
+
+var (
+	// defaults maps a protocol buffer struct type to a slice of the fields,
+	// with its scalar fields set to their proto-declared non-zero default values.
+	defaultMu sync.RWMutex
+	defaults  = make(map[reflect.Type]defaultMessage)
+
+	int32PtrType = reflect.TypeOf((*int32)(nil))
+)
+
+// defaultMessage represents information about the default values of a message.
+type defaultMessage struct {
+	scalars []scalarField
+	nested  []int // struct field index of nested messages
+}
+
+type scalarField struct {
+	index int          // struct field index
+	kind  reflect.Kind // element type (the T in *T or []T)
+	value interface{}  // the proto-declared default value, or nil
+}
+
+// t is a struct type.
+func buildDefaultMessage(t reflect.Type) (dm defaultMessage) {
+	sprop := GetProperties(t)
+	for _, prop := range sprop.Prop {
+		fi, ok := sprop.decoderTags.get(prop.Tag)
+		if !ok {
+			// XXX_unrecognized
+			continue
+		}
+		ft := t.Field(fi).Type
+
+		sf, nested, err := fieldDefault(ft, prop)
+		switch {
+		case err != nil:
+			log.Print(err)
+		case nested:
+			dm.nested = append(dm.nested, fi)
+		case sf != nil:
+			sf.index = fi
+			dm.scalars = append(dm.scalars, *sf)
+		}
+	}
+
+	return dm
+}
+
+// fieldDefault returns the scalarField for field type ft.
+// sf will be nil if the field can not have a default.
+// nestedMessage will be true if this is a nested message.
+// Note that sf.index is not set on return.
+func fieldDefault(ft reflect.Type, prop *Properties) (sf *scalarField, nestedMessage bool, err error) {
+	var canHaveDefault bool
+	switch ft.Kind() {
+	case reflect.Ptr:
+		if ft.Elem().Kind() == reflect.Struct {
+			nestedMessage = true
+		} else {
+			canHaveDefault = true // proto2 scalar field
+		}
+
+	case reflect.Slice:
+		switch ft.Elem().Kind() {
+		case reflect.Ptr:
+			nestedMessage = true // repeated message
+		case reflect.Uint8:
+			canHaveDefault = true // bytes field
+		}
+
+	case reflect.Map:
+		if ft.Elem().Kind() == reflect.Ptr {
+			nestedMessage = true // map with message values
+		}
+	}
+
+	if !canHaveDefault {
+		if nestedMessage {
+			return nil, true, nil
+		}
+		return nil, false, nil
+	}
+
+	// We now know that ft is a pointer or slice.
+	sf = &scalarField{kind: ft.Elem().Kind()}
+
+	// scalar fields without defaults
+	if !prop.HasDefault {
+		return sf, false, nil
+	}
+
+	// a scalar field: either *T or []byte
+	switch ft.Elem().Kind() {
+	case reflect.Bool:
+		x, err := strconv.ParseBool(prop.Default)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default bool %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Float32:
+		x, err := strconv.ParseFloat(prop.Default, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float32 %q: %v", prop.Default, err)
+		}
+		sf.value = float32(x)
+	case reflect.Float64:
+		x, err := strconv.ParseFloat(prop.Default, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Int32:
+		x, err := strconv.ParseInt(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int32 %q: %v", prop.Default, err)
+		}
+		sf.value = int32(x)
+	case reflect.Int64:
+		x, err := strconv.ParseInt(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.String:
+		sf.value = prop.Default
+	case reflect.Uint8:
+		// []byte (not *uint8)
+		sf.value = []byte(prop.Default)
+	case reflect.Uint32:
+		x, err := strconv.ParseUint(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint32 %q: %v", prop.Default, err)
+		}
+		sf.value = uint32(x)
+	case reflect.Uint64:
+		x, err := strconv.ParseUint(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	default:
+		return nil, false, fmt.Errorf("proto: unhandled def kind %v", ft.Elem().Kind())
+	}
+
+	return sf, false, nil
+}
+
+// Map fields may have key types of non-float scalars, strings and enums.
+// The easiest way to sort them in some deterministic order is to use fmt.
+// If this turns out to be inefficient we can always consider other options,
+// such as doing a Schwartzian transform.
+
+func mapKeys(vs []reflect.Value) sort.Interface {
+	s := mapKeySorter{
+		vs: vs,
+		// default Less function: textual comparison
+		less: func(a, b reflect.Value) bool {
+			return fmt.Sprint(a.Interface()) < fmt.Sprint(b.Interface())
+		},
+	}
+
+	// Type specialization per https://developers.google.com/protocol-buffers/docs/proto#maps;
+	// numeric keys are sorted numerically.
+	if len(vs) == 0 {
+		return s
+	}
+	switch vs[0].Kind() {
+	case reflect.Int32, reflect.Int64:
+		s.less = func(a, b reflect.Value) bool { return a.Int() < b.Int() }
+	case reflect.Uint32, reflect.Uint64:
+		s.less = func(a, b reflect.Value) bool { return a.Uint() < b.Uint() }
+	}
+
+	return s
+}
+
+type mapKeySorter struct {
+	vs   []reflect.Value
+	less func(a, b reflect.Value) bool
+}
+
+func (s mapKeySorter) Len() int      { return len(s.vs) }
+func (s mapKeySorter) Swap(i, j int) { s.vs[i], s.vs[j] = s.vs[j], s.vs[i] }
+func (s mapKeySorter) Less(i, j int) bool {
+	return s.less(s.vs[i], s.vs[j])
+}
+
+// isProto3Zero reports whether v is a zero proto3 value.
+func isProto3Zero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint32, reflect.Uint64:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.String:
+		return v.String() == ""
+	}
+	return false
+}

vendor/github.com/golang/protobuf/proto/message_set.go

@@ -0,0 +1,287 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Support for message sets.
+ */
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+)
+
+// ErrNoMessageTypeId occurs when a protocol buffer does not have a message type ID.
+// A message type ID is required for storing a protocol buffer in a message set.
+var ErrNoMessageTypeId = errors.New("proto does not have a message type ID")
+
+// The first two types (_MessageSet_Item and MessageSet)
+// model what the protocol compiler produces for the following protocol message:
+//   message MessageSet {
+//     repeated group Item = 1 {
+//       required int32 type_id = 2;
+//       required string message = 3;
+//     };
+//   }
+// That is the MessageSet wire format. We can't use a proto to generate these
+// because that would introduce a circular dependency between it and this package.
+//
+// When a proto1 proto has a field that looks like:
+//   optional message<MessageSet> info = 3;
+// the protocol compiler produces a field in the generated struct that looks like:
+//   Info *_proto_.MessageSet  `protobuf:"bytes,3,opt,name=info"`
+// The package is automatically inserted so there is no need for that proto file to
+// import this package.
+
+type _MessageSet_Item struct {
+	TypeId  *int32 `protobuf:"varint,2,req,name=type_id"`
+	Message []byte `protobuf:"bytes,3,req,name=message"`
+}
+
+type MessageSet struct {
+	Item             []*_MessageSet_Item `protobuf:"group,1,rep"`
+	XXX_unrecognized []byte
+	// TODO: caching?
+}
+
+// Make sure MessageSet is a Message.
+var _ Message = (*MessageSet)(nil)
+
+// messageTypeIder is an interface satisfied by a protocol buffer type
+// that may be stored in a MessageSet.
+type messageTypeIder interface {
+	MessageTypeId() int32
+}
+
+func (ms *MessageSet) find(pb Message) *_MessageSet_Item {
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return nil
+	}
+	id := mti.MessageTypeId()
+	for _, item := range ms.Item {
+		if *item.TypeId == id {
+			return item
+		}
+	}
+	return nil
+}
+
+func (ms *MessageSet) Has(pb Message) bool {
+	if ms.find(pb) != nil {
+		return true
+	}
+	return false
+}
+
+func (ms *MessageSet) Unmarshal(pb Message) error {
+	if item := ms.find(pb); item != nil {
+		return Unmarshal(item.Message, pb)
+	}
+	if _, ok := pb.(messageTypeIder); !ok {
+		return ErrNoMessageTypeId
+	}
+	return nil // TODO: return error instead?
+}
+
+func (ms *MessageSet) Marshal(pb Message) error {
+	msg, err := Marshal(pb)
+	if err != nil {
+		return err
+	}
+	if item := ms.find(pb); item != nil {
+		// reuse existing item
+		item.Message = msg
+		return nil
+	}
+
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return ErrNoMessageTypeId
+	}
+
+	mtid := mti.MessageTypeId()
+	ms.Item = append(ms.Item, &_MessageSet_Item{
+		TypeId:  &mtid,
+		Message: msg,
+	})
+	return nil
+}
+
+func (ms *MessageSet) Reset()         { *ms = MessageSet{} }
+func (ms *MessageSet) String() string { return CompactTextString(ms) }
+func (*MessageSet) ProtoMessage()     {}
+
+// Support for the message_set_wire_format message option.
+
+func skipVarint(buf []byte) []byte {
+	i := 0
+	for ; buf[i]&0x80 != 0; i++ {
+	}
+	return buf[i+1:]
+}
+
+// MarshalMessageSet encodes the extension map represented by m in the message set wire format.
+// It is called by generated Marshal methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSet(m map[int32]Extension) ([]byte, error) {
+	if err := encodeExtensionMap(m); err != nil {
+		return nil, err
+	}
+
+	// Sort extension IDs to provide a deterministic encoding.
+	// See also enc_map in encode.go.
+	ids := make([]int, 0, len(m))
+	for id := range m {
+		ids = append(ids, int(id))
+	}
+	sort.Ints(ids)
+
+	ms := &MessageSet{Item: make([]*_MessageSet_Item, 0, len(m))}
+	for _, id := range ids {
+		e := m[int32(id)]
+		// Remove the wire type and field number varint, as well as the length varint.
+		msg := skipVarint(skipVarint(e.enc))
+
+		ms.Item = append(ms.Item, &_MessageSet_Item{
+			TypeId:  Int32(int32(id)),
+			Message: msg,
+		})
+	}
+	return Marshal(ms)
+}
+
+// UnmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
+// It is called by generated Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSet(buf []byte, m map[int32]Extension) error {
+	ms := new(MessageSet)
+	if err := Unmarshal(buf, ms); err != nil {
+		return err
+	}
+	for _, item := range ms.Item {
+		id := *item.TypeId
+		msg := item.Message
+
+		// Restore wire type and field number varint, plus length varint.
+		// Be careful to preserve duplicate items.
+		b := EncodeVarint(uint64(id)<<3 | WireBytes)
+		if ext, ok := m[id]; ok {
+			// Existing data; rip off the tag and length varint
+			// so we join the new data correctly.
+			// We can assume that ext.enc is set because we are unmarshaling.
+			o := ext.enc[len(b):]   // skip wire type and field number
+			_, n := DecodeVarint(o) // calculate length of length varint
+			o = o[n:]               // skip length varint
+			msg = append(o, msg...) // join old data and new data
+		}
+		b = append(b, EncodeVarint(uint64(len(msg)))...)
+		b = append(b, msg...)
+
+		m[id] = Extension{enc: b}
+	}
+	return nil
+}
+
+// MarshalMessageSetJSON encodes the extension map represented by m in JSON format.
+// It is called by generated MarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSetJSON(m map[int32]Extension) ([]byte, error) {
+	var b bytes.Buffer
+	b.WriteByte('{')
+
+	// Process the map in key order for deterministic output.
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids)) // int32Slice defined in text.go
+
+	for i, id := range ids {
+		ext := m[id]
+		if i > 0 {
+			b.WriteByte(',')
+		}
+
+		msd, ok := messageSetMap[id]
+		if !ok {
+			// Unknown type; we can't render it, so skip it.
+			continue
+		}
+		fmt.Fprintf(&b, `"[%s]":`, msd.name)
+
+		x := ext.value
+		if x == nil {
+			x = reflect.New(msd.t.Elem()).Interface()
+			if err := Unmarshal(ext.enc, x.(Message)); err != nil {
+				return nil, err
+			}
+		}
+		d, err := json.Marshal(x)
+		if err != nil {
+			return nil, err
+		}
+		b.Write(d)
+	}
+	b.WriteByte('}')
+	return b.Bytes(), nil
+}
+
+// UnmarshalMessageSetJSON decodes the extension map encoded in buf in JSON format.
+// It is called by generated UnmarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSetJSON(buf []byte, m map[int32]Extension) error {
+	// Common-case fast path.
+	if len(buf) == 0 || bytes.Equal(buf, []byte("{}")) {
+		return nil
+	}
+
+	// This is fairly tricky, and it's not clear that it is needed.
+	return errors.New("TODO: UnmarshalMessageSetJSON not yet implemented")
+}
+
+// A global registry of types that can be used in a MessageSet.
+
+var messageSetMap = make(map[int32]messageSetDesc)
+
+type messageSetDesc struct {
+	t    reflect.Type // pointer to struct
+	name string
+}
+
+// RegisterMessageSetType is called from the generated code.
+func RegisterMessageSetType(m Message, fieldNum int32, name string) {
+	messageSetMap[fieldNum] = messageSetDesc{
+		t:    reflect.TypeOf(m),
+		name: name,
+	}
+}

vendor/github.com/golang/protobuf/proto/pointer_reflect.go

@@ -0,0 +1,479 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// +build appengine
+
+// This file contains an implementation of proto field accesses using package reflect.
+// It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can
+// be used on App Engine.
+
+package proto
+
+import (
+	"math"
+	"reflect"
+)
+
+// A structPointer is a pointer to a struct.
+type structPointer struct {
+	v reflect.Value
+}
+
+// toStructPointer returns a structPointer equivalent to the given reflect value.
+// The reflect value must itself be a pointer to a struct.
+func toStructPointer(v reflect.Value) structPointer {
+	return structPointer{v}
+}
+
+// IsNil reports whether p is nil.
+func structPointer_IsNil(p structPointer) bool {
+	return p.v.IsNil()
+}
+
+// Interface returns the struct pointer as an interface value.
+func structPointer_Interface(p structPointer, _ reflect.Type) interface{} {
+	return p.v.Interface()
+}
+
+// A field identifies a field in a struct, accessible from a structPointer.
+// In this implementation, a field is identified by the sequence of field indices
+// passed to reflect's FieldByIndex.
+type field []int
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return f.Index
+}
+
+// invalidField is an invalid field identifier.
+var invalidField = field(nil)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool { return f != nil }
+
+// field returns the given field in the struct as a reflect value.
+func structPointer_field(p structPointer, f field) reflect.Value {
+	// Special case: an extension map entry with a value of type T
+	// passes a *T to the struct-handling code with a zero field,
+	// expecting that it will be treated as equivalent to *struct{ X T },
+	// which has the same memory layout. We have to handle that case
+	// specially, because reflect will panic if we call FieldByIndex on a
+	// non-struct.
+	if f == nil {
+		return p.v.Elem()
+	}
+
+	return p.v.Elem().FieldByIndex(f)
+}
+
+// ifield returns the given field in the struct as an interface value.
+func structPointer_ifield(p structPointer, f field) interface{} {
+	return structPointer_field(p, f).Addr().Interface()
+}
+
+// Bytes returns the address of a []byte field in the struct.
+func structPointer_Bytes(p structPointer, f field) *[]byte {
+	return structPointer_ifield(p, f).(*[]byte)
+}
+
+// BytesSlice returns the address of a [][]byte field in the struct.
+func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
+	return structPointer_ifield(p, f).(*[][]byte)
+}
+
+// Bool returns the address of a *bool field in the struct.
+func structPointer_Bool(p structPointer, f field) **bool {
+	return structPointer_ifield(p, f).(**bool)
+}
+
+// BoolVal returns the address of a bool field in the struct.
+func structPointer_BoolVal(p structPointer, f field) *bool {
+	return structPointer_ifield(p, f).(*bool)
+}
+
+// BoolSlice returns the address of a []bool field in the struct.
+func structPointer_BoolSlice(p structPointer, f field) *[]bool {
+	return structPointer_ifield(p, f).(*[]bool)
+}
+
+// String returns the address of a *string field in the struct.
+func structPointer_String(p structPointer, f field) **string {
+	return structPointer_ifield(p, f).(**string)
+}
+
+// StringVal returns the address of a string field in the struct.
+func structPointer_StringVal(p structPointer, f field) *string {
+	return structPointer_ifield(p, f).(*string)
+}
+
+// StringSlice returns the address of a []string field in the struct.
+func structPointer_StringSlice(p structPointer, f field) *[]string {
+	return structPointer_ifield(p, f).(*[]string)
+}
+
+// ExtMap returns the address of an extension map field in the struct.
+func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
+	return structPointer_ifield(p, f).(*map[int32]Extension)
+}
+
+// NewAt returns the reflect.Value for a pointer to a field in the struct.
+func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
+	return structPointer_field(p, f).Addr()
+}
+
+// SetStructPointer writes a *struct field in the struct.
+func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
+	structPointer_field(p, f).Set(q.v)
+}
+
+// GetStructPointer reads a *struct field in the struct.
+func structPointer_GetStructPointer(p structPointer, f field) structPointer {
+	return structPointer{structPointer_field(p, f)}
+}
+
+// StructPointerSlice the address of a []*struct field in the struct.
+func structPointer_StructPointerSlice(p structPointer, f field) structPointerSlice {
+	return structPointerSlice{structPointer_field(p, f)}
+}
+
+// A structPointerSlice represents the address of a slice of pointers to structs
+// (themselves messages or groups). That is, v.Type() is *[]*struct{...}.
+type structPointerSlice struct {
+	v reflect.Value
+}
+
+func (p structPointerSlice) Len() int                  { return p.v.Len() }
+func (p structPointerSlice) Index(i int) structPointer { return structPointer{p.v.Index(i)} }
+func (p structPointerSlice) Append(q structPointer) {
+	p.v.Set(reflect.Append(p.v, q.v))
+}
+
+var (
+	int32Type   = reflect.TypeOf(int32(0))
+	uint32Type  = reflect.TypeOf(uint32(0))
+	float32Type = reflect.TypeOf(float32(0))
+	int64Type   = reflect.TypeOf(int64(0))
+	uint64Type  = reflect.TypeOf(uint64(0))
+	float64Type = reflect.TypeOf(float64(0))
+)
+
+// A word32 represents a field of type *int32, *uint32, *float32, or *enum.
+// That is, v.Type() is *int32, *uint32, *float32, or *enum and v is assignable.
+type word32 struct {
+	v reflect.Value
+}
+
+// IsNil reports whether p is nil.
+func word32_IsNil(p word32) bool {
+	return p.v.IsNil()
+}
+
+// Set sets p to point at a newly allocated word with bits set to x.
+func word32_Set(p word32, o *Buffer, x uint32) {
+	t := p.v.Type().Elem()
+	switch t {
+	case int32Type:
+		if len(o.int32s) == 0 {
+			o.int32s = make([]int32, uint32PoolSize)
+		}
+		o.int32s[0] = int32(x)
+		p.v.Set(reflect.ValueOf(&o.int32s[0]))
+		o.int32s = o.int32s[1:]
+		return
+	case uint32Type:
+		if len(o.uint32s) == 0 {
+			o.uint32s = make([]uint32, uint32PoolSize)
+		}
+		o.uint32s[0] = x
+		p.v.Set(reflect.ValueOf(&o.uint32s[0]))
+		o.uint32s = o.uint32s[1:]
+		return
+	case float32Type:
+		if len(o.float32s) == 0 {
+			o.float32s = make([]float32, uint32PoolSize)
+		}
+		o.float32s[0] = math.Float32frombits(x)
+		p.v.Set(reflect.ValueOf(&o.float32s[0]))
+		o.float32s = o.float32s[1:]
+		return
+	}
+
+	// must be enum
+	p.v.Set(reflect.New(t))
+	p.v.Elem().SetInt(int64(int32(x)))
+}
+
+// Get gets the bits pointed at by p, as a uint32.
+func word32_Get(p word32) uint32 {
+	elem := p.v.Elem()
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32 returns a reference to a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32(p structPointer, f field) word32 {
+	return word32{structPointer_field(p, f)}
+}
+
+// A word32Val represents a field of type int32, uint32, float32, or enum.
+// That is, v.Type() is int32, uint32, float32, or enum and v is assignable.
+type word32Val struct {
+	v reflect.Value
+}
+
+// Set sets *p to x.
+func word32Val_Set(p word32Val, x uint32) {
+	switch p.v.Type() {
+	case int32Type:
+		p.v.SetInt(int64(x))
+		return
+	case uint32Type:
+		p.v.SetUint(uint64(x))
+		return
+	case float32Type:
+		p.v.SetFloat(float64(math.Float32frombits(x)))
+		return
+	}
+
+	// must be enum
+	p.v.SetInt(int64(int32(x)))
+}
+
+// Get gets the bits pointed at by p, as a uint32.
+func word32Val_Get(p word32Val) uint32 {
+	elem := p.v
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32Val returns a reference to a int32, uint32, float32, or enum field in the struct.
+func structPointer_Word32Val(p structPointer, f field) word32Val {
+	return word32Val{structPointer_field(p, f)}
+}
+
+// A word32Slice is a slice of 32-bit values.
+// That is, v.Type() is []int32, []uint32, []float32, or []enum.
+type word32Slice struct {
+	v reflect.Value
+}
+
+func (p word32Slice) Append(x uint32) {
+	n, m := p.v.Len(), p.v.Cap()
+	if n < m {
+		p.v.SetLen(n + 1)
+	} else {
+		t := p.v.Type().Elem()
+		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
+	}
+	elem := p.v.Index(n)
+	switch elem.Kind() {
+	case reflect.Int32:
+		elem.SetInt(int64(int32(x)))
+	case reflect.Uint32:
+		elem.SetUint(uint64(x))
+	case reflect.Float32:
+		elem.SetFloat(float64(math.Float32frombits(x)))
+	}
+}
+
+func (p word32Slice) Len() int {
+	return p.v.Len()
+}
+
+func (p word32Slice) Index(i int) uint32 {
+	elem := p.v.Index(i)
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32Slice returns a reference to a []int32, []uint32, []float32, or []enum field in the struct.
+func structPointer_Word32Slice(p structPointer, f field) word32Slice {
+	return word32Slice{structPointer_field(p, f)}
+}
+
+// word64 is like word32 but for 64-bit values.
+type word64 struct {
+	v reflect.Value
+}
+
+func word64_Set(p word64, o *Buffer, x uint64) {
+	t := p.v.Type().Elem()
+	switch t {
+	case int64Type:
+		if len(o.int64s) == 0 {
+			o.int64s = make([]int64, uint64PoolSize)
+		}
+		o.int64s[0] = int64(x)
+		p.v.Set(reflect.ValueOf(&o.int64s[0]))
+		o.int64s = o.int64s[1:]
+		return
+	case uint64Type:
+		if len(o.uint64s) == 0 {
+			o.uint64s = make([]uint64, uint64PoolSize)
+		}
+		o.uint64s[0] = x
+		p.v.Set(reflect.ValueOf(&o.uint64s[0]))
+		o.uint64s = o.uint64s[1:]
+		return
+	case float64Type:
+		if len(o.float64s) == 0 {
+			o.float64s = make([]float64, uint64PoolSize)
+		}
+		o.float64s[0] = math.Float64frombits(x)
+		p.v.Set(reflect.ValueOf(&o.float64s[0]))
+		o.float64s = o.float64s[1:]
+		return
+	}
+	panic("unreachable")
+}
+
+func word64_IsNil(p word64) bool {
+	return p.v.IsNil()
+}
+
+func word64_Get(p word64) uint64 {
+	elem := p.v.Elem()
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return elem.Uint()
+	case reflect.Float64:
+		return math.Float64bits(elem.Float())
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64(p structPointer, f field) word64 {
+	return word64{structPointer_field(p, f)}
+}
+
+// word64Val is like word32Val but for 64-bit values.
+type word64Val struct {
+	v reflect.Value
+}
+
+func word64Val_Set(p word64Val, o *Buffer, x uint64) {
+	switch p.v.Type() {
+	case int64Type:
+		p.v.SetInt(int64(x))
+		return
+	case uint64Type:
+		p.v.SetUint(x)
+		return
+	case float64Type:
+		p.v.SetFloat(math.Float64frombits(x))
+		return
+	}
+	panic("unreachable")
+}
+
+func word64Val_Get(p word64Val) uint64 {
+	elem := p.v
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return elem.Uint()
+	case reflect.Float64:
+		return math.Float64bits(elem.Float())
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64Val(p structPointer, f field) word64Val {
+	return word64Val{structPointer_field(p, f)}
+}
+
+type word64Slice struct {
+	v reflect.Value
+}
+
+func (p word64Slice) Append(x uint64) {
+	n, m := p.v.Len(), p.v.Cap()
+	if n < m {
+		p.v.SetLen(n + 1)
+	} else {
+		t := p.v.Type().Elem()
+		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
+	}
+	elem := p.v.Index(n)
+	switch elem.Kind() {
+	case reflect.Int64:
+		elem.SetInt(int64(int64(x)))
+	case reflect.Uint64:
+		elem.SetUint(uint64(x))
+	case reflect.Float64:
+		elem.SetFloat(float64(math.Float64frombits(x)))
+	}
+}
+
+func (p word64Slice) Len() int {
+	return p.v.Len()
+}
+
+func (p word64Slice) Index(i int) uint64 {
+	elem := p.v.Index(i)
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return uint64(elem.Uint())
+	case reflect.Float64:
+		return math.Float64bits(float64(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64Slice(p structPointer, f field) word64Slice {
+	return word64Slice{structPointer_field(p, f)}
+}

vendor/github.com/golang/protobuf/proto/pointer_unsafe.go

@@ -0,0 +1,266 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// +build !appengine
+
+// This file contains the implementation of the proto field accesses using package unsafe.
+
+package proto
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// NOTE: These type_Foo functions would more idiomatically be methods,
+// but Go does not allow methods on pointer types, and we must preserve
+// some pointer type for the garbage collector. We use these
+// funcs with clunky names as our poor approximation to methods.
+//
+// An alternative would be
+//	type structPointer struct { p unsafe.Pointer }
+// but that does not registerize as well.
+
+// A structPointer is a pointer to a struct.
+type structPointer unsafe.Pointer
+
+// toStructPointer returns a structPointer equivalent to the given reflect value.
+func toStructPointer(v reflect.Value) structPointer {
+	return structPointer(unsafe.Pointer(v.Pointer()))
+}
+
+// IsNil reports whether p is nil.
+func structPointer_IsNil(p structPointer) bool {
+	return p == nil
+}
+
+// Interface returns the struct pointer, assumed to have element type t,
+// as an interface value.
+func structPointer_Interface(p structPointer, t reflect.Type) interface{} {
+	return reflect.NewAt(t, unsafe.Pointer(p)).Interface()
+}
+
+// A field identifies a field in a struct, accessible from a structPointer.
+// In this implementation, a field is identified by its byte offset from the start of the struct.
+type field uintptr
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return field(f.Offset)
+}
+
+// invalidField is an invalid field identifier.
+const invalidField = ^field(0)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool {
+	return f != ^field(0)
+}
+
+// Bytes returns the address of a []byte field in the struct.
+func structPointer_Bytes(p structPointer, f field) *[]byte {
+	return (*[]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BytesSlice returns the address of a [][]byte field in the struct.
+func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
+	return (*[][]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// Bool returns the address of a *bool field in the struct.
+func structPointer_Bool(p structPointer, f field) **bool {
+	return (**bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BoolVal returns the address of a bool field in the struct.
+func structPointer_BoolVal(p structPointer, f field) *bool {
+	return (*bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BoolSlice returns the address of a []bool field in the struct.
+func structPointer_BoolSlice(p structPointer, f field) *[]bool {
+	return (*[]bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// String returns the address of a *string field in the struct.
+func structPointer_String(p structPointer, f field) **string {
+	return (**string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StringVal returns the address of a string field in the struct.
+func structPointer_StringVal(p structPointer, f field) *string {
+	return (*string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StringSlice returns the address of a []string field in the struct.
+func structPointer_StringSlice(p structPointer, f field) *[]string {
+	return (*[]string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// ExtMap returns the address of an extension map field in the struct.
+func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
+	return (*map[int32]Extension)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// NewAt returns the reflect.Value for a pointer to a field in the struct.
+func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
+	return reflect.NewAt(typ, unsafe.Pointer(uintptr(p)+uintptr(f)))
+}
+
+// SetStructPointer writes a *struct field in the struct.
+func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
+	*(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f))) = q
+}
+
+// GetStructPointer reads a *struct field in the struct.
+func structPointer_GetStructPointer(p structPointer, f field) structPointer {
+	return *(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StructPointerSlice the address of a []*struct field in the struct.
+func structPointer_StructPointerSlice(p structPointer, f field) *structPointerSlice {
+	return (*structPointerSlice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// A structPointerSlice represents a slice of pointers to structs (themselves submessages or groups).
+type structPointerSlice []structPointer
+
+func (v *structPointerSlice) Len() int                  { return len(*v) }
+func (v *structPointerSlice) Index(i int) structPointer { return (*v)[i] }
+func (v *structPointerSlice) Append(p structPointer)    { *v = append(*v, p) }
+
+// A word32 is the address of a "pointer to 32-bit value" field.
+type word32 **uint32
+
+// IsNil reports whether *v is nil.
+func word32_IsNil(p word32) bool {
+	return *p == nil
+}
+
+// Set sets *v to point at a newly allocated word set to x.
+func word32_Set(p word32, o *Buffer, x uint32) {
+	if len(o.uint32s) == 0 {
+		o.uint32s = make([]uint32, uint32PoolSize)
+	}
+	o.uint32s[0] = x
+	*p = &o.uint32s[0]
+	o.uint32s = o.uint32s[1:]
+}
+
+// Get gets the value pointed at by *v.
+func word32_Get(p word32) uint32 {
+	return **p
+}
+
+// Word32 returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32(p structPointer, f field) word32 {
+	return word32((**uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// A word32Val is the address of a 32-bit value field.
+type word32Val *uint32
+
+// Set sets *p to x.
+func word32Val_Set(p word32Val, x uint32) {
+	*p = x
+}
+
+// Get gets the value pointed at by p.
+func word32Val_Get(p word32Val) uint32 {
+	return *p
+}
+
+// Word32Val returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32Val(p structPointer, f field) word32Val {
+	return word32Val((*uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// A word32Slice is a slice of 32-bit values.
+type word32Slice []uint32
+
+func (v *word32Slice) Append(x uint32)    { *v = append(*v, x) }
+func (v *word32Slice) Len() int           { return len(*v) }
+func (v *word32Slice) Index(i int) uint32 { return (*v)[i] }
+
+// Word32Slice returns the address of a []int32, []uint32, []float32, or []enum field in the struct.
+func structPointer_Word32Slice(p structPointer, f field) *word32Slice {
+	return (*word32Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// word64 is like word32 but for 64-bit values.
+type word64 **uint64
+
+func word64_Set(p word64, o *Buffer, x uint64) {
+	if len(o.uint64s) == 0 {
+		o.uint64s = make([]uint64, uint64PoolSize)
+	}
+	o.uint64s[0] = x
+	*p = &o.uint64s[0]
+	o.uint64s = o.uint64s[1:]
+}
+
+func word64_IsNil(p word64) bool {
+	return *p == nil
+}
+
+func word64_Get(p word64) uint64 {
+	return **p
+}
+
+func structPointer_Word64(p structPointer, f field) word64 {
+	return word64((**uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// word64Val is like word32Val but for 64-bit values.
+type word64Val *uint64
+
+func word64Val_Set(p word64Val, o *Buffer, x uint64) {
+	*p = x
+}
+
+func word64Val_Get(p word64Val) uint64 {
+	return *p
+}
+
+func structPointer_Word64Val(p structPointer, f field) word64Val {
+	return word64Val((*uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// word64Slice is like word32Slice but for 64-bit values.
+type word64Slice []uint64
+
+func (v *word64Slice) Append(x uint64)    { *v = append(*v, x) }
+func (v *word64Slice) Len() int           { return len(*v) }
+func (v *word64Slice) Index(i int) uint64 { return (*v)[i] }
+
+func structPointer_Word64Slice(p structPointer, f field) *word64Slice {
+	return (*word64Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}

vendor/github.com/golang/protobuf/proto/properties.go

@@ -0,0 +1,805 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"fmt"
+	"os"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+const debug bool = false
+
+// Constants that identify the encoding of a value on the wire.
+const (
+	WireVarint     = 0
+	WireFixed64    = 1
+	WireBytes      = 2
+	WireStartGroup = 3
+	WireEndGroup   = 4
+	WireFixed32    = 5
+)
+
+const startSize = 10 // initial slice/string sizes
+
+// Encoders are defined in encode.go
+// An encoder outputs the full representation of a field, including its
+// tag and encoder type.
+type encoder func(p *Buffer, prop *Properties, base structPointer) error
+
+// A valueEncoder encodes a single integer in a particular encoding.
+type valueEncoder func(o *Buffer, x uint64) error
+
+// Sizers are defined in encode.go
+// A sizer returns the encoded size of a field, including its tag and encoder
+// type.
+type sizer func(prop *Properties, base structPointer) int
+
+// A valueSizer returns the encoded size of a single integer in a particular
+// encoding.
+type valueSizer func(x uint64) int
+
+// Decoders are defined in decode.go
+// A decoder creates a value from its wire representation.
+// Unrecognized subelements are saved in unrec.
+type decoder func(p *Buffer, prop *Properties, base structPointer) error
+
+// A valueDecoder decodes a single integer in a particular encoding.
+type valueDecoder func(o *Buffer) (x uint64, err error)
+
+// A oneofMarshaler does the marshaling for all oneof fields in a message.
+type oneofMarshaler func(Message, *Buffer) error
+
+// A oneofUnmarshaler does the unmarshaling for a oneof field in a message.
+type oneofUnmarshaler func(Message, int, int, *Buffer) (bool, error)
+
+// tagMap is an optimization over map[int]int for typical protocol buffer
+// use-cases. Encoded protocol buffers are often in tag order with small tag
+// numbers.
+type tagMap struct {
+	fastTags []int
+	slowTags map[int]int
+}
+
+// tagMapFastLimit is the upper bound on the tag number that will be stored in
+// the tagMap slice rather than its map.
+const tagMapFastLimit = 1024
+
+func (p *tagMap) get(t int) (int, bool) {
+	if t > 0 && t < tagMapFastLimit {
+		if t >= len(p.fastTags) {
+			return 0, false
+		}
+		fi := p.fastTags[t]
+		return fi, fi >= 0
+	}
+	fi, ok := p.slowTags[t]
+	return fi, ok
+}
+
+func (p *tagMap) put(t int, fi int) {
+	if t > 0 && t < tagMapFastLimit {
+		for len(p.fastTags) < t+1 {
+			p.fastTags = append(p.fastTags, -1)
+		}
+		p.fastTags[t] = fi
+		return
+	}
+	if p.slowTags == nil {
+		p.slowTags = make(map[int]int)
+	}
+	p.slowTags[t] = fi
+}
+
+// StructProperties represents properties for all the fields of a struct.
+// decoderTags and decoderOrigNames should only be used by the decoder.
+type StructProperties struct {
+	Prop             []*Properties  // properties for each field
+	reqCount         int            // required count
+	decoderTags      tagMap         // map from proto tag to struct field number
+	decoderOrigNames map[string]int // map from original name to struct field number
+	order            []int          // list of struct field numbers in tag order
+	unrecField       field          // field id of the XXX_unrecognized []byte field
+	extendable       bool           // is this an extendable proto
+
+	oneofMarshaler   oneofMarshaler
+	oneofUnmarshaler oneofUnmarshaler
+	stype            reflect.Type
+
+	// OneofTypes contains information about the oneof fields in this message.
+	// It is keyed by the original name of a field.
+	OneofTypes map[string]*OneofProperties
+}
+
+// OneofProperties represents information about a specific field in a oneof.
+type OneofProperties struct {
+	Type  reflect.Type // pointer to generated struct type for this oneof field
+	Field int          // struct field number of the containing oneof in the message
+	Prop  *Properties
+}
+
+// Implement the sorting interface so we can sort the fields in tag order, as recommended by the spec.
+// See encode.go, (*Buffer).enc_struct.
+
+func (sp *StructProperties) Len() int { return len(sp.order) }
+func (sp *StructProperties) Less(i, j int) bool {
+	return sp.Prop[sp.order[i]].Tag < sp.Prop[sp.order[j]].Tag
+}
+func (sp *StructProperties) Swap(i, j int) { sp.order[i], sp.order[j] = sp.order[j], sp.order[i] }
+
+// Properties represents the protocol-specific behavior of a single struct field.
+type Properties struct {
+	Name     string // name of the field, for error messages
+	OrigName string // original name before protocol compiler (always set)
+	Wire     string
+	WireType int
+	Tag      int
+	Required bool
+	Optional bool
+	Repeated bool
+	Packed   bool   // relevant for repeated primitives only
+	Enum     string // set for enum types only
+	proto3   bool   // whether this is known to be a proto3 field; set for []byte only
+	oneof    bool   // whether this is a oneof field
+
+	Default    string // default value
+	HasDefault bool   // whether an explicit default was provided
+	def_uint64 uint64
+
+	enc           encoder
+	valEnc        valueEncoder // set for bool and numeric types only
+	field         field
+	tagcode       []byte // encoding of EncodeVarint((Tag<<3)|WireType)
+	tagbuf        [8]byte
+	stype         reflect.Type      // set for struct types only
+	sprop         *StructProperties // set for struct types only
+	isMarshaler   bool
+	isUnmarshaler bool
+
+	mtype    reflect.Type // set for map types only
+	mkeyprop *Properties  // set for map types only
+	mvalprop *Properties  // set for map types only
+
+	size    sizer
+	valSize valueSizer // set for bool and numeric types only
+
+	dec    decoder
+	valDec valueDecoder // set for bool and numeric types only
+
+	// If this is a packable field, this will be the decoder for the packed version of the field.
+	packedDec decoder
+}
+
+// String formats the properties in the protobuf struct field tag style.
+func (p *Properties) String() string {
+	s := p.Wire
+	s = ","
+	s += strconv.Itoa(p.Tag)
+	if p.Required {
+		s += ",req"
+	}
+	if p.Optional {
+		s += ",opt"
+	}
+	if p.Repeated {
+		s += ",rep"
+	}
+	if p.Packed {
+		s += ",packed"
+	}
+	if p.OrigName != p.Name {
+		s += ",name=" + p.OrigName
+	}
+	if p.proto3 {
+		s += ",proto3"
+	}
+	if p.oneof {
+		s += ",oneof"
+	}
+	if len(p.Enum) > 0 {
+		s += ",enum=" + p.Enum
+	}
+	if p.HasDefault {
+		s += ",def=" + p.Default
+	}
+	return s
+}
+
+// Parse populates p by parsing a string in the protobuf struct field tag style.
+func (p *Properties) Parse(s string) {
+	// "bytes,49,opt,name=foo,def=hello!"
+	fields := strings.Split(s, ",") // breaks def=, but handled below.
+	if len(fields) < 2 {
+		fmt.Fprintf(os.Stderr, "proto: tag has too few fields: %q\n", s)
+		return
+	}
+
+	p.Wire = fields[0]
+	switch p.Wire {
+	case "varint":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeVarint
+		p.valDec = (*Buffer).DecodeVarint
+		p.valSize = sizeVarint
+	case "fixed32":
+		p.WireType = WireFixed32
+		p.valEnc = (*Buffer).EncodeFixed32
+		p.valDec = (*Buffer).DecodeFixed32
+		p.valSize = sizeFixed32
+	case "fixed64":
+		p.WireType = WireFixed64
+		p.valEnc = (*Buffer).EncodeFixed64
+		p.valDec = (*Buffer).DecodeFixed64
+		p.valSize = sizeFixed64
+	case "zigzag32":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeZigzag32
+		p.valDec = (*Buffer).DecodeZigzag32
+		p.valSize = sizeZigzag32
+	case "zigzag64":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeZigzag64
+		p.valDec = (*Buffer).DecodeZigzag64
+		p.valSize = sizeZigzag64
+	case "bytes", "group":
+		p.WireType = WireBytes
+		// no numeric converter for non-numeric types
+	default:
+		fmt.Fprintf(os.Stderr, "proto: tag has unknown wire type: %q\n", s)
+		return
+	}
+
+	var err error
+	p.Tag, err = strconv.Atoi(fields[1])
+	if err != nil {
+		return
+	}
+
+	for i := 2; i < len(fields); i++ {
+		f := fields[i]
+		switch {
+		case f == "req":
+			p.Required = true
+		case f == "opt":
+			p.Optional = true
+		case f == "rep":
+			p.Repeated = true
+		case f == "packed":
+			p.Packed = true
+		case strings.HasPrefix(f, "name="):
+			p.OrigName = f[5:]
+		case strings.HasPrefix(f, "enum="):
+			p.Enum = f[5:]
+		case f == "proto3":
+			p.proto3 = true
+		case f == "oneof":
+			p.oneof = true
+		case strings.HasPrefix(f, "def="):
+			p.HasDefault = true
+			p.Default = f[4:] // rest of string
+			if i+1 < len(fields) {
+				// Commas aren't escaped, and def is always last.
+				p.Default += "," + strings.Join(fields[i+1:], ",")
+				break
+			}
+		}
+	}
+}
+
+func logNoSliceEnc(t1, t2 reflect.Type) {
+	fmt.Fprintf(os.Stderr, "proto: no slice oenc for %T = []%T\n", t1, t2)
+}
+
+var protoMessageType = reflect.TypeOf((*Message)(nil)).Elem()
+
+// Initialize the fields for encoding and decoding.
+func (p *Properties) setEncAndDec(typ reflect.Type, f *reflect.StructField, lockGetProp bool) {
+	p.enc = nil
+	p.dec = nil
+	p.size = nil
+
+	switch t1 := typ; t1.Kind() {
+	default:
+		fmt.Fprintf(os.Stderr, "proto: no coders for %v\n", t1)
+
+	// proto3 scalar types
+
+	case reflect.Bool:
+		p.enc = (*Buffer).enc_proto3_bool
+		p.dec = (*Buffer).dec_proto3_bool
+		p.size = size_proto3_bool
+	case reflect.Int32:
+		p.enc = (*Buffer).enc_proto3_int32
+		p.dec = (*Buffer).dec_proto3_int32
+		p.size = size_proto3_int32
+	case reflect.Uint32:
+		p.enc = (*Buffer).enc_proto3_uint32
+		p.dec = (*Buffer).dec_proto3_int32 // can reuse
+		p.size = size_proto3_uint32
+	case reflect.Int64, reflect.Uint64:
+		p.enc = (*Buffer).enc_proto3_int64
+		p.dec = (*Buffer).dec_proto3_int64
+		p.size = size_proto3_int64
+	case reflect.Float32:
+		p.enc = (*Buffer).enc_proto3_uint32 // can just treat them as bits
+		p.dec = (*Buffer).dec_proto3_int32
+		p.size = size_proto3_uint32
+	case reflect.Float64:
+		p.enc = (*Buffer).enc_proto3_int64 // can just treat them as bits
+		p.dec = (*Buffer).dec_proto3_int64
+		p.size = size_proto3_int64
+	case reflect.String:
+		p.enc = (*Buffer).enc_proto3_string
+		p.dec = (*Buffer).dec_proto3_string
+		p.size = size_proto3_string
+
+	case reflect.Ptr:
+		switch t2 := t1.Elem(); t2.Kind() {
+		default:
+			fmt.Fprintf(os.Stderr, "proto: no encoder function for %v -> %v\n", t1, t2)
+			break
+		case reflect.Bool:
+			p.enc = (*Buffer).enc_bool
+			p.dec = (*Buffer).dec_bool
+			p.size = size_bool
+		case reflect.Int32:
+			p.enc = (*Buffer).enc_int32
+			p.dec = (*Buffer).dec_int32
+			p.size = size_int32
+		case reflect.Uint32:
+			p.enc = (*Buffer).enc_uint32
+			p.dec = (*Buffer).dec_int32 // can reuse
+			p.size = size_uint32
+		case reflect.Int64, reflect.Uint64:
+			p.enc = (*Buffer).enc_int64
+			p.dec = (*Buffer).dec_int64
+			p.size = size_int64
+		case reflect.Float32:
+			p.enc = (*Buffer).enc_uint32 // can just treat them as bits
+			p.dec = (*Buffer).dec_int32
+			p.size = size_uint32
+		case reflect.Float64:
+			p.enc = (*Buffer).enc_int64 // can just treat them as bits
+			p.dec = (*Buffer).dec_int64
+			p.size = size_int64
+		case reflect.String:
+			p.enc = (*Buffer).enc_string
+			p.dec = (*Buffer).dec_string
+			p.size = size_string
+		case reflect.Struct:
+			p.stype = t1.Elem()
+			p.isMarshaler = isMarshaler(t1)
+			p.isUnmarshaler = isUnmarshaler(t1)
+			if p.Wire == "bytes" {
+				p.enc = (*Buffer).enc_struct_message
+				p.dec = (*Buffer).dec_struct_message
+				p.size = size_struct_message
+			} else {
+				p.enc = (*Buffer).enc_struct_group
+				p.dec = (*Buffer).dec_struct_group
+				p.size = size_struct_group
+			}
+		}
+
+	case reflect.Slice:
+		switch t2 := t1.Elem(); t2.Kind() {
+		default:
+			logNoSliceEnc(t1, t2)
+			break
+		case reflect.Bool:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_bool
+				p.size = size_slice_packed_bool
+			} else {
+				p.enc = (*Buffer).enc_slice_bool
+				p.size = size_slice_bool
+			}
+			p.dec = (*Buffer).dec_slice_bool
+			p.packedDec = (*Buffer).dec_slice_packed_bool
+		case reflect.Int32:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_int32
+				p.size = size_slice_packed_int32
+			} else {
+				p.enc = (*Buffer).enc_slice_int32
+				p.size = size_slice_int32
+			}
+			p.dec = (*Buffer).dec_slice_int32
+			p.packedDec = (*Buffer).dec_slice_packed_int32
+		case reflect.Uint32:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_uint32
+				p.size = size_slice_packed_uint32
+			} else {
+				p.enc = (*Buffer).enc_slice_uint32
+				p.size = size_slice_uint32
+			}
+			p.dec = (*Buffer).dec_slice_int32
+			p.packedDec = (*Buffer).dec_slice_packed_int32
+		case reflect.Int64, reflect.Uint64:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_int64
+				p.size = size_slice_packed_int64
+			} else {
+				p.enc = (*Buffer).enc_slice_int64
+				p.size = size_slice_int64
+			}
+			p.dec = (*Buffer).dec_slice_int64
+			p.packedDec = (*Buffer).dec_slice_packed_int64
+		case reflect.Uint8:
+			p.enc = (*Buffer).enc_slice_byte
+			p.dec = (*Buffer).dec_slice_byte
+			p.size = size_slice_byte
+			// This is a []byte, which is either a bytes field,
+			// or the value of a map field. In the latter case,
+			// we always encode an empty []byte, so we should not
+			// use the proto3 enc/size funcs.
+			// f == nil iff this is the key/value of a map field.
+			if p.proto3 && f != nil {
+				p.enc = (*Buffer).enc_proto3_slice_byte
+				p.size = size_proto3_slice_byte
+			}
+		case reflect.Float32, reflect.Float64:
+			switch t2.Bits() {
+			case 32:
+				// can just treat them as bits
+				if p.Packed {
+					p.enc = (*Buffer).enc_slice_packed_uint32
+					p.size = size_slice_packed_uint32
+				} else {
+					p.enc = (*Buffer).enc_slice_uint32
+					p.size = size_slice_uint32
+				}
+				p.dec = (*Buffer).dec_slice_int32
+				p.packedDec = (*Buffer).dec_slice_packed_int32
+			case 64:
+				// can just treat them as bits
+				if p.Packed {
+					p.enc = (*Buffer).enc_slice_packed_int64
+					p.size = size_slice_packed_int64
+				} else {
+					p.enc = (*Buffer).enc_slice_int64
+					p.size = size_slice_int64
+				}
+				p.dec = (*Buffer).dec_slice_int64
+				p.packedDec = (*Buffer).dec_slice_packed_int64
+			default:
+				logNoSliceEnc(t1, t2)
+				break
+			}
+		case reflect.String:
+			p.enc = (*Buffer).enc_slice_string
+			p.dec = (*Buffer).dec_slice_string
+			p.size = size_slice_string
+		case reflect.Ptr:
+			switch t3 := t2.Elem(); t3.Kind() {
+			default:
+				fmt.Fprintf(os.Stderr, "proto: no ptr oenc for %T -> %T -> %T\n", t1, t2, t3)
+				break
+			case reflect.Struct:
+				p.stype = t2.Elem()
+				p.isMarshaler = isMarshaler(t2)
+				p.isUnmarshaler = isUnmarshaler(t2)
+				if p.Wire == "bytes" {
+					p.enc = (*Buffer).enc_slice_struct_message
+					p.dec = (*Buffer).dec_slice_struct_message
+					p.size = size_slice_struct_message
+				} else {
+					p.enc = (*Buffer).enc_slice_struct_group
+					p.dec = (*Buffer).dec_slice_struct_group
+					p.size = size_slice_struct_group
+				}
+			}
+		case reflect.Slice:
+			switch t2.Elem().Kind() {
+			default:
+				fmt.Fprintf(os.Stderr, "proto: no slice elem oenc for %T -> %T -> %T\n", t1, t2, t2.Elem())
+				break
+			case reflect.Uint8:
+				p.enc = (*Buffer).enc_slice_slice_byte
+				p.dec = (*Buffer).dec_slice_slice_byte
+				p.size = size_slice_slice_byte
+			}
+		}
+
+	case reflect.Map:
+		p.enc = (*Buffer).enc_new_map
+		p.dec = (*Buffer).dec_new_map
+		p.size = size_new_map
+
+		p.mtype = t1
+		p.mkeyprop = &Properties{}
+		p.mkeyprop.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp)
+		p.mvalprop = &Properties{}
+		vtype := p.mtype.Elem()
+		if vtype.Kind() != reflect.Ptr && vtype.Kind() != reflect.Slice {
+			// The value type is not a message (*T) or bytes ([]byte),
+			// so we need encoders for the pointer to this type.
+			vtype = reflect.PtrTo(vtype)
+		}
+		p.mvalprop.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp)
+	}
+
+	// precalculate tag code
+	wire := p.WireType
+	if p.Packed {
+		wire = WireBytes
+	}
+	x := uint32(p.Tag)<<3 | uint32(wire)
+	i := 0
+	for i = 0; x > 127; i++ {
+		p.tagbuf[i] = 0x80 | uint8(x&0x7F)
+		x >>= 7
+	}
+	p.tagbuf[i] = uint8(x)
+	p.tagcode = p.tagbuf[0 : i+1]
+
+	if p.stype != nil {
+		if lockGetProp {
+			p.sprop = GetProperties(p.stype)
+		} else {
+			p.sprop = getPropertiesLocked(p.stype)
+		}
+	}
+}
+
+var (
+	marshalerType   = reflect.TypeOf((*Marshaler)(nil)).Elem()
+	unmarshalerType = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+)
+
+// isMarshaler reports whether type t implements Marshaler.
+func isMarshaler(t reflect.Type) bool {
+	// We're checking for (likely) pointer-receiver methods
+	// so if t is not a pointer, something is very wrong.
+	// The calls above only invoke isMarshaler on pointer types.
+	if t.Kind() != reflect.Ptr {
+		panic("proto: misuse of isMarshaler")
+	}
+	return t.Implements(marshalerType)
+}
+
+// isUnmarshaler reports whether type t implements Unmarshaler.
+func isUnmarshaler(t reflect.Type) bool {
+	// We're checking for (likely) pointer-receiver methods
+	// so if t is not a pointer, something is very wrong.
+	// The calls above only invoke isUnmarshaler on pointer types.
+	if t.Kind() != reflect.Ptr {
+		panic("proto: misuse of isUnmarshaler")
+	}
+	return t.Implements(unmarshalerType)
+}
+
+// Init populates the properties from a protocol buffer struct tag.
+func (p *Properties) Init(typ reflect.Type, name, tag string, f *reflect.StructField) {
+	p.init(typ, name, tag, f, true)
+}
+
+func (p *Properties) init(typ reflect.Type, name, tag string, f *reflect.StructField, lockGetProp bool) {
+	// "bytes,49,opt,def=hello!"
+	p.Name = name
+	p.OrigName = name
+	if f != nil {
+		p.field = toField(f)
+	}
+	if tag == "" {
+		return
+	}
+	p.Parse(tag)
+	p.setEncAndDec(typ, f, lockGetProp)
+}
+
+var (
+	propertiesMu  sync.RWMutex
+	propertiesMap = make(map[reflect.Type]*StructProperties)
+)
+
+// GetProperties returns the list of properties for the type represented by t.
+// t must represent a generated struct type of a protocol message.
+func GetProperties(t reflect.Type) *StructProperties {
+	if t.Kind() != reflect.Struct {
+		panic("proto: type must have kind struct")
+	}
+
+	// Most calls to GetProperties in a long-running program will be
+	// retrieving details for types we have seen before.
+	propertiesMu.RLock()
+	sprop, ok := propertiesMap[t]
+	propertiesMu.RUnlock()
+	if ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return sprop
+	}
+
+	propertiesMu.Lock()
+	sprop = getPropertiesLocked(t)
+	propertiesMu.Unlock()
+	return sprop
+}
+
+// getPropertiesLocked requires that propertiesMu is held.
+func getPropertiesLocked(t reflect.Type) *StructProperties {
+	if prop, ok := propertiesMap[t]; ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return prop
+	}
+	if collectStats {
+		stats.Cmiss++
+	}
+
+	prop := new(StructProperties)
+	// in case of recursive protos, fill this in now.
+	propertiesMap[t] = prop
+
+	// build properties
+	prop.extendable = reflect.PtrTo(t).Implements(extendableProtoType)
+	prop.unrecField = invalidField
+	prop.Prop = make([]*Properties, t.NumField())
+	prop.order = make([]int, t.NumField())
+
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		p := new(Properties)
+		name := f.Name
+		p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false)
+
+		if f.Name == "XXX_extensions" { // special case
+			p.enc = (*Buffer).enc_map
+			p.dec = nil // not needed
+			p.size = size_map
+		}
+		if f.Name == "XXX_unrecognized" { // special case
+			prop.unrecField = toField(&f)
+		}
+		oneof := f.Tag.Get("protobuf_oneof") != "" // special case
+		prop.Prop[i] = p
+		prop.order[i] = i
+		if debug {
+			print(i, " ", f.Name, " ", t.String(), " ")
+			if p.Tag > 0 {
+				print(p.String())
+			}
+			print("\n")
+		}
+		if p.enc == nil && !strings.HasPrefix(f.Name, "XXX_") && !oneof {
+			fmt.Fprintln(os.Stderr, "proto: no encoder for", f.Name, f.Type.String(), "[GetProperties]")
+		}
+	}
+
+	// Re-order prop.order.
+	sort.Sort(prop)
+
+	type oneofMessage interface {
+		XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), []interface{})
+	}
+	if om, ok := reflect.Zero(reflect.PtrTo(t)).Interface().(oneofMessage); ok {
+		var oots []interface{}
+		prop.oneofMarshaler, prop.oneofUnmarshaler, oots = om.XXX_OneofFuncs()
+		prop.stype = t
+
+		// Interpret oneof metadata.
+		prop.OneofTypes = make(map[string]*OneofProperties)
+		for _, oot := range oots {
+			oop := &OneofProperties{
+				Type: reflect.ValueOf(oot).Type(), // *T
+				Prop: new(Properties),
+			}
+			sft := oop.Type.Elem().Field(0)
+			oop.Prop.Name = sft.Name
+			oop.Prop.Parse(sft.Tag.Get("protobuf"))
+			// There will be exactly one interface field that
+			// this new value is assignable to.
+			for i := 0; i < t.NumField(); i++ {
+				f := t.Field(i)
+				if f.Type.Kind() != reflect.Interface {
+					continue
+				}
+				if !oop.Type.AssignableTo(f.Type) {
+					continue
+				}
+				oop.Field = i
+				break
+			}
+			prop.OneofTypes[oop.Prop.OrigName] = oop
+		}
+	}
+
+	// build required counts
+	// build tags
+	reqCount := 0
+	prop.decoderOrigNames = make(map[string]int)
+	for i, p := range prop.Prop {
+		if strings.HasPrefix(p.Name, "XXX_") {
+			// Internal fields should not appear in tags/origNames maps.
+			// They are handled specially when encoding and decoding.
+			continue
+		}
+		if p.Required {
+			reqCount++
+		}
+		prop.decoderTags.put(p.Tag, i)
+		prop.decoderOrigNames[p.OrigName] = i
+	}
+	prop.reqCount = reqCount
+
+	return prop
+}
+
+// Return the Properties object for the x[0]'th field of the structure.
+func propByIndex(t reflect.Type, x []int) *Properties {
+	if len(x) != 1 {
+		fmt.Fprintf(os.Stderr, "proto: field index dimension %d (not 1) for type %s\n", len(x), t)
+		return nil
+	}
+	prop := GetProperties(t)
+	return prop.Prop[x[0]]
+}
+
+// Get the address and type of a pointer to a struct from an interface.
+func getbase(pb Message) (t reflect.Type, b structPointer, err error) {
+	if pb == nil {
+		err = ErrNil
+		return
+	}
+	// get the reflect type of the pointer to the struct.
+	t = reflect.TypeOf(pb)
+	// get the address of the struct.
+	value := reflect.ValueOf(pb)
+	b = toStructPointer(value)
+	return
+}
+
+// A global registry of enum types.
+// The generated code will register the generated maps by calling RegisterEnum.
+
+var enumValueMaps = make(map[string]map[string]int32)
+
+// RegisterEnum is called from the generated code to install the enum descriptor
+// maps into the global table to aid parsing text format protocol buffers.
+func RegisterEnum(typeName string, unusedNameMap map[int32]string, valueMap map[string]int32) {
+	if _, ok := enumValueMaps[typeName]; ok {
+		panic("proto: duplicate enum registered: " + typeName)
+	}
+	enumValueMaps[typeName] = valueMap
+}

vendor/github.com/golang/protobuf/proto/text.go

@@ -0,0 +1,797 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+// Functions for writing the text protocol buffer format.
+
+import (
+	"bufio"
+	"bytes"
+	"encoding"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"reflect"
+	"sort"
+	"strings"
+)
+
+var (
+	newline         = []byte("\n")
+	spaces          = []byte("                                        ")
+	gtNewline       = []byte(">\n")
+	endBraceNewline = []byte("}\n")
+	backslashN      = []byte{'\\', 'n'}
+	backslashR      = []byte{'\\', 'r'}
+	backslashT      = []byte{'\\', 't'}
+	backslashDQ     = []byte{'\\', '"'}
+	backslashBS     = []byte{'\\', '\\'}
+	posInf          = []byte("inf")
+	negInf          = []byte("-inf")
+	nan             = []byte("nan")
+)
+
+type writer interface {
+	io.Writer
+	WriteByte(byte) error
+}
+
+// textWriter is an io.Writer that tracks its indentation level.
+type textWriter struct {
+	ind      int
+	complete bool // if the current position is a complete line
+	compact  bool // whether to write out as a one-liner
+	w        writer
+}
+
+func (w *textWriter) WriteString(s string) (n int, err error) {
+	if !strings.Contains(s, "\n") {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		w.complete = false
+		return io.WriteString(w.w, s)
+	}
+	// WriteString is typically called without newlines, so this
+	// codepath and its copy are rare.  We copy to avoid
+	// duplicating all of Write's logic here.
+	return w.Write([]byte(s))
+}
+
+func (w *textWriter) Write(p []byte) (n int, err error) {
+	newlines := bytes.Count(p, newline)
+	if newlines == 0 {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		n, err = w.w.Write(p)
+		w.complete = false
+		return n, err
+	}
+
+	frags := bytes.SplitN(p, newline, newlines+1)
+	if w.compact {
+		for i, frag := range frags {
+			if i > 0 {
+				if err := w.w.WriteByte(' '); err != nil {
+					return n, err
+				}
+				n++
+			}
+			nn, err := w.w.Write(frag)
+			n += nn
+			if err != nil {
+				return n, err
+			}
+		}
+		return n, nil
+	}
+
+	for i, frag := range frags {
+		if w.complete {
+			w.writeIndent()
+		}
+		nn, err := w.w.Write(frag)
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		if i+1 < len(frags) {
+			if err := w.w.WriteByte('\n'); err != nil {
+				return n, err
+			}
+			n++
+		}
+	}
+	w.complete = len(frags[len(frags)-1]) == 0
+	return n, nil
+}
+
+func (w *textWriter) WriteByte(c byte) error {
+	if w.compact && c == '\n' {
+		c = ' '
+	}
+	if !w.compact && w.complete {
+		w.writeIndent()
+	}
+	err := w.w.WriteByte(c)
+	w.complete = c == '\n'
+	return err
+}
+
+func (w *textWriter) indent() { w.ind++ }
+
+func (w *textWriter) unindent() {
+	if w.ind == 0 {
+		log.Printf("proto: textWriter unindented too far")
+		return
+	}
+	w.ind--
+}
+
+func writeName(w *textWriter, props *Properties) error {
+	if _, err := w.WriteString(props.OrigName); err != nil {
+		return err
+	}
+	if props.Wire != "group" {
+		return w.WriteByte(':')
+	}
+	return nil
+}
+
+var (
+	messageSetType = reflect.TypeOf((*MessageSet)(nil)).Elem()
+)
+
+// raw is the interface satisfied by RawMessage.
+type raw interface {
+	Bytes() []byte
+}
+
+func writeStruct(w *textWriter, sv reflect.Value) error {
+	if sv.Type() == messageSetType {
+		return writeMessageSet(w, sv.Addr().Interface().(*MessageSet))
+	}
+
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < sv.NumField(); i++ {
+		fv := sv.Field(i)
+		props := sprops.Prop[i]
+		name := st.Field(i).Name
+
+		if strings.HasPrefix(name, "XXX_") {
+			// There are two XXX_ fields:
+			//   XXX_unrecognized []byte
+			//   XXX_extensions   map[int32]proto.Extension
+			// The first is handled here;
+			// the second is handled at the bottom of this function.
+			if name == "XXX_unrecognized" && !fv.IsNil() {
+				if err := writeUnknownStruct(w, fv.Interface().([]byte)); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Ptr && fv.IsNil() {
+			// Field not filled in. This could be an optional field or
+			// a required field that wasn't filled in. Either way, there
+			// isn't anything we can show for it.
+			continue
+		}
+		if fv.Kind() == reflect.Slice && fv.IsNil() {
+			// Repeated field that is empty, or a bytes field that is unused.
+			continue
+		}
+
+		if props.Repeated && fv.Kind() == reflect.Slice {
+			// Repeated field.
+			for j := 0; j < fv.Len(); j++ {
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				v := fv.Index(j)
+				if v.Kind() == reflect.Ptr && v.IsNil() {
+					// A nil message in a repeated field is not valid,
+					// but we can handle that more gracefully than panicking.
+					if _, err := w.Write([]byte("<nil>\n")); err != nil {
+						return err
+					}
+					continue
+				}
+				if err := writeAny(w, v, props); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Map {
+			// Map fields are rendered as a repeated struct with key/value fields.
+			keys := fv.MapKeys()
+			sort.Sort(mapKeys(keys))
+			for _, key := range keys {
+				val := fv.MapIndex(key)
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				// open struct
+				if err := w.WriteByte('<'); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				w.indent()
+				// key
+				if _, err := w.WriteString("key:"); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				if err := writeAny(w, key, props.mkeyprop); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+				// nil values aren't legal, but we can avoid panicking because of them.
+				if val.Kind() != reflect.Ptr || !val.IsNil() {
+					// value
+					if _, err := w.WriteString("value:"); err != nil {
+						return err
+					}
+					if !w.compact {
+						if err := w.WriteByte(' '); err != nil {
+							return err
+						}
+					}
+					if err := writeAny(w, val, props.mvalprop); err != nil {
+						return err
+					}
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				// close struct
+				w.unindent()
+				if err := w.WriteByte('>'); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if props.proto3 && fv.Kind() == reflect.Slice && fv.Len() == 0 {
+			// empty bytes field
+			continue
+		}
+		if fv.Kind() != reflect.Ptr && fv.Kind() != reflect.Slice {
+			// proto3 non-repeated scalar field; skip if zero value
+			if isProto3Zero(fv) {
+				continue
+			}
+		}
+
+		if fv.Kind() == reflect.Interface {
+			// Check if it is a oneof.
+			if st.Field(i).Tag.Get("protobuf_oneof") != "" {
+				// fv is nil, or holds a pointer to generated struct.
+				// That generated struct has exactly one field,
+				// which has a protobuf struct tag.
+				if fv.IsNil() {
+					continue
+				}
+				inner := fv.Elem().Elem() // interface -> *T -> T
+				tag := inner.Type().Field(0).Tag.Get("protobuf")
+				props = new(Properties) // Overwrite the outer props var, but not its pointee.
+				props.Parse(tag)
+				// Write the value in the oneof, not the oneof itself.
+				fv = inner.Field(0)
+
+				// Special case to cope with malformed messages gracefully:
+				// If the value in the oneof is a nil pointer, don't panic
+				// in writeAny.
+				if fv.Kind() == reflect.Ptr && fv.IsNil() {
+					// Use errors.New so writeAny won't render quotes.
+					msg := errors.New("/* nil */")
+					fv = reflect.ValueOf(&msg).Elem()
+				}
+			}
+		}
+
+		if err := writeName(w, props); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		if b, ok := fv.Interface().(raw); ok {
+			if err := writeRaw(w, b.Bytes()); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Enums have a String method, so writeAny will work fine.
+		if err := writeAny(w, fv, props); err != nil {
+			return err
+		}
+
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+
+	// Extensions (the XXX_extensions field).
+	pv := sv.Addr()
+	if pv.Type().Implements(extendableProtoType) {
+		if err := writeExtensions(w, pv); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// writeRaw writes an uninterpreted raw message.
+func writeRaw(w *textWriter, b []byte) error {
+	if err := w.WriteByte('<'); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	w.indent()
+	if err := writeUnknownStruct(w, b); err != nil {
+		return err
+	}
+	w.unindent()
+	if err := w.WriteByte('>'); err != nil {
+		return err
+	}
+	return nil
+}
+
+// writeAny writes an arbitrary field.
+func writeAny(w *textWriter, v reflect.Value, props *Properties) error {
+	v = reflect.Indirect(v)
+
+	// Floats have special cases.
+	if v.Kind() == reflect.Float32 || v.Kind() == reflect.Float64 {
+		x := v.Float()
+		var b []byte
+		switch {
+		case math.IsInf(x, 1):
+			b = posInf
+		case math.IsInf(x, -1):
+			b = negInf
+		case math.IsNaN(x):
+			b = nan
+		}
+		if b != nil {
+			_, err := w.Write(b)
+			return err
+		}
+		// Other values are handled below.
+	}
+
+	// We don't attempt to serialise every possible value type; only those
+	// that can occur in protocol buffers.
+	switch v.Kind() {
+	case reflect.Slice:
+		// Should only be a []byte; repeated fields are handled in writeStruct.
+		if err := writeString(w, string(v.Interface().([]byte))); err != nil {
+			return err
+		}
+	case reflect.String:
+		if err := writeString(w, v.String()); err != nil {
+			return err
+		}
+	case reflect.Struct:
+		// Required/optional group/message.
+		var bra, ket byte = '<', '>'
+		if props != nil && props.Wire == "group" {
+			bra, ket = '{', '}'
+		}
+		if err := w.WriteByte(bra); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte('\n'); err != nil {
+				return err
+			}
+		}
+		w.indent()
+		if tm, ok := v.Interface().(encoding.TextMarshaler); ok {
+			text, err := tm.MarshalText()
+			if err != nil {
+				return err
+			}
+			if _, err = w.Write(text); err != nil {
+				return err
+			}
+		} else if err := writeStruct(w, v); err != nil {
+			return err
+		}
+		w.unindent()
+		if err := w.WriteByte(ket); err != nil {
+			return err
+		}
+	default:
+		_, err := fmt.Fprint(w, v.Interface())
+		return err
+	}
+	return nil
+}
+
+// equivalent to C's isprint.
+func isprint(c byte) bool {
+	return c >= 0x20 && c < 0x7f
+}
+
+// writeString writes a string in the protocol buffer text format.
+// It is similar to strconv.Quote except we don't use Go escape sequences,
+// we treat the string as a byte sequence, and we use octal escapes.
+// These differences are to maintain interoperability with the other
+// languages' implementations of the text format.
+func writeString(w *textWriter, s string) error {
+	// use WriteByte here to get any needed indent
+	if err := w.WriteByte('"'); err != nil {
+		return err
+	}
+	// Loop over the bytes, not the runes.
+	for i := 0; i < len(s); i++ {
+		var err error
+		// Divergence from C++: we don't escape apostrophes.
+		// There's no need to escape them, and the C++ parser
+		// copes with a naked apostrophe.
+		switch c := s[i]; c {
+		case '\n':
+			_, err = w.w.Write(backslashN)
+		case '\r':
+			_, err = w.w.Write(backslashR)
+		case '\t':
+			_, err = w.w.Write(backslashT)
+		case '"':
+			_, err = w.w.Write(backslashDQ)
+		case '\\':
+			_, err = w.w.Write(backslashBS)
+		default:
+			if isprint(c) {
+				err = w.w.WriteByte(c)
+			} else {
+				_, err = fmt.Fprintf(w.w, "\\%03o", c)
+			}
+		}
+		if err != nil {
+			return err
+		}
+	}
+	return w.WriteByte('"')
+}
+
+func writeMessageSet(w *textWriter, ms *MessageSet) error {
+	for _, item := range ms.Item {
+		id := *item.TypeId
+		if msd, ok := messageSetMap[id]; ok {
+			// Known message set type.
+			if _, err := fmt.Fprintf(w, "[%s]: <\n", msd.name); err != nil {
+				return err
+			}
+			w.indent()
+
+			pb := reflect.New(msd.t.Elem())
+			if err := Unmarshal(item.Message, pb.Interface().(Message)); err != nil {
+				if _, err := fmt.Fprintf(w, "/* bad message: %v */\n", err); err != nil {
+					return err
+				}
+			} else {
+				if err := writeStruct(w, pb.Elem()); err != nil {
+					return err
+				}
+			}
+		} else {
+			// Unknown type.
+			if _, err := fmt.Fprintf(w, "[%d]: <\n", id); err != nil {
+				return err
+			}
+			w.indent()
+			if err := writeUnknownStruct(w, item.Message); err != nil {
+				return err
+			}
+		}
+		w.unindent()
+		if _, err := w.Write(gtNewline); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeUnknownStruct(w *textWriter, data []byte) (err error) {
+	if !w.compact {
+		if _, err := fmt.Fprintf(w, "/* %d unknown bytes */\n", len(data)); err != nil {
+			return err
+		}
+	}
+	b := NewBuffer(data)
+	for b.index < len(b.buf) {
+		x, err := b.DecodeVarint()
+		if err != nil {
+			_, err := fmt.Fprintf(w, "/* %v */\n", err)
+			return err
+		}
+		wire, tag := x&7, x>>3
+		if wire == WireEndGroup {
+			w.unindent()
+			if _, err := w.Write(endBraceNewline); err != nil {
+				return err
+			}
+			continue
+		}
+		if _, err := fmt.Fprint(w, tag); err != nil {
+			return err
+		}
+		if wire != WireStartGroup {
+			if err := w.WriteByte(':'); err != nil {
+				return err
+			}
+		}
+		if !w.compact || wire == WireStartGroup {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		switch wire {
+		case WireBytes:
+			buf, e := b.DecodeRawBytes(false)
+			if e == nil {
+				_, err = fmt.Fprintf(w, "%q", buf)
+			} else {
+				_, err = fmt.Fprintf(w, "/* %v */", e)
+			}
+		case WireFixed32:
+			x, err = b.DecodeFixed32()
+			err = writeUnknownInt(w, x, err)
+		case WireFixed64:
+			x, err = b.DecodeFixed64()
+			err = writeUnknownInt(w, x, err)
+		case WireStartGroup:
+			err = w.WriteByte('{')
+			w.indent()
+		case WireVarint:
+			x, err = b.DecodeVarint()
+			err = writeUnknownInt(w, x, err)
+		default:
+			_, err = fmt.Fprintf(w, "/* unknown wire type %d */", wire)
+		}
+		if err != nil {
+			return err
+		}
+		if err = w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeUnknownInt(w *textWriter, x uint64, err error) error {
+	if err == nil {
+		_, err = fmt.Fprint(w, x)
+	} else {
+		_, err = fmt.Fprintf(w, "/* %v */", err)
+	}
+	return err
+}
+
+type int32Slice []int32
+
+func (s int32Slice) Len() int           { return len(s) }
+func (s int32Slice) Less(i, j int) bool { return s[i] < s[j] }
+func (s int32Slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// writeExtensions writes all the extensions in pv.
+// pv is assumed to be a pointer to a protocol message struct that is extendable.
+func writeExtensions(w *textWriter, pv reflect.Value) error {
+	emap := extensionMaps[pv.Type().Elem()]
+	ep := pv.Interface().(extendableProto)
+
+	// Order the extensions by ID.
+	// This isn't strictly necessary, but it will give us
+	// canonical output, which will also make testing easier.
+	m := ep.ExtensionMap()
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids))
+
+	for _, extNum := range ids {
+		ext := m[extNum]
+		var desc *ExtensionDesc
+		if emap != nil {
+			desc = emap[extNum]
+		}
+		if desc == nil {
+			// Unknown extension.
+			if err := writeUnknownStruct(w, ext.enc); err != nil {
+				return err
+			}
+			continue
+		}
+
+		pb, err := GetExtension(ep, desc)
+		if err != nil {
+			return fmt.Errorf("failed getting extension: %v", err)
+		}
+
+		// Repeated extensions will appear as a slice.
+		if !desc.repeated() {
+			if err := writeExtension(w, desc.Name, pb); err != nil {
+				return err
+			}
+		} else {
+			v := reflect.ValueOf(pb)
+			for i := 0; i < v.Len(); i++ {
+				if err := writeExtension(w, desc.Name, v.Index(i).Interface()); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func writeExtension(w *textWriter, name string, pb interface{}) error {
+	if _, err := fmt.Fprintf(w, "[%s]:", name); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte(' '); err != nil {
+			return err
+		}
+	}
+	if err := writeAny(w, reflect.ValueOf(pb), nil); err != nil {
+		return err
+	}
+	if err := w.WriteByte('\n'); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (w *textWriter) writeIndent() {
+	if !w.complete {
+		return
+	}
+	remain := w.ind * 2
+	for remain > 0 {
+		n := remain
+		if n > len(spaces) {
+			n = len(spaces)
+		}
+		w.w.Write(spaces[:n])
+		remain -= n
+	}
+	w.complete = false
+}
+
+func marshalText(w io.Writer, pb Message, compact bool) error {
+	val := reflect.ValueOf(pb)
+	if pb == nil || val.IsNil() {
+		w.Write([]byte("<nil>"))
+		return nil
+	}
+	var bw *bufio.Writer
+	ww, ok := w.(writer)
+	if !ok {
+		bw = bufio.NewWriter(w)
+		ww = bw
+	}
+	aw := &textWriter{
+		w:        ww,
+		complete: true,
+		compact:  compact,
+	}
+
+	if tm, ok := pb.(encoding.TextMarshaler); ok {
+		text, err := tm.MarshalText()
+		if err != nil {
+			return err
+		}
+		if _, err = aw.Write(text); err != nil {
+			return err
+		}
+		if bw != nil {
+			return bw.Flush()
+		}
+		return nil
+	}
+	// Dereference the received pointer so we don't have outer < and >.
+	v := reflect.Indirect(val)
+	if err := writeStruct(aw, v); err != nil {
+		return err
+	}
+	if bw != nil {
+		return bw.Flush()
+	}
+	return nil
+}
+
+// MarshalText writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func MarshalText(w io.Writer, pb Message) error {
+	return marshalText(w, pb, false)
+}
+
+// MarshalTextString is the same as MarshalText, but returns the string directly.
+func MarshalTextString(pb Message) string {
+	var buf bytes.Buffer
+	marshalText(&buf, pb, false)
+	return buf.String()
+}
+
+// CompactText writes a given protocol buffer in compact text format (one line).
+func CompactText(w io.Writer, pb Message) error { return marshalText(w, pb, true) }
+
+// CompactTextString is the same as CompactText, but returns the string directly.
+func CompactTextString(pb Message) string {
+	var buf bytes.Buffer
+	marshalText(&buf, pb, true)
+	return buf.String()
+}

vendor/github.com/golang/protobuf/proto/text_parser.go

@@ -0,0 +1,784 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+// Functions for parsing the Text protocol buffer format.
+// TODO: message sets.
+
+import (
+	"encoding"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+type ParseError struct {
+	Message string
+	Line    int // 1-based line number
+	Offset  int // 0-based byte offset from start of input
+}
+
+func (p *ParseError) Error() string {
+	if p.Line == 1 {
+		// show offset only for first line
+		return fmt.Sprintf("line 1.%d: %v", p.Offset, p.Message)
+	}
+	return fmt.Sprintf("line %d: %v", p.Line, p.Message)
+}
+
+type token struct {
+	value    string
+	err      *ParseError
+	line     int    // line number
+	offset   int    // byte number from start of input, not start of line
+	unquoted string // the unquoted version of value, if it was a quoted string
+}
+
+func (t *token) String() string {
+	if t.err == nil {
+		return fmt.Sprintf("%q (line=%d, offset=%d)", t.value, t.line, t.offset)
+	}
+	return fmt.Sprintf("parse error: %v", t.err)
+}
+
+type textParser struct {
+	s            string // remaining input
+	done         bool   // whether the parsing is finished (success or error)
+	backed       bool   // whether back() was called
+	offset, line int
+	cur          token
+}
+
+func newTextParser(s string) *textParser {
+	p := new(textParser)
+	p.s = s
+	p.line = 1
+	p.cur.line = 1
+	return p
+}
+
+func (p *textParser) errorf(format string, a ...interface{}) *ParseError {
+	pe := &ParseError{fmt.Sprintf(format, a...), p.cur.line, p.cur.offset}
+	p.cur.err = pe
+	p.done = true
+	return pe
+}
+
+// Numbers and identifiers are matched by [-+._A-Za-z0-9]
+func isIdentOrNumberChar(c byte) bool {
+	switch {
+	case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z':
+		return true
+	case '0' <= c && c <= '9':
+		return true
+	}
+	switch c {
+	case '-', '+', '.', '_':
+		return true
+	}
+	return false
+}
+
+func isWhitespace(c byte) bool {
+	switch c {
+	case ' ', '\t', '\n', '\r':
+		return true
+	}
+	return false
+}
+
+func (p *textParser) skipWhitespace() {
+	i := 0
+	for i < len(p.s) && (isWhitespace(p.s[i]) || p.s[i] == '#') {
+		if p.s[i] == '#' {
+			// comment; skip to end of line or input
+			for i < len(p.s) && p.s[i] != '\n' {
+				i++
+			}
+			if i == len(p.s) {
+				break
+			}
+		}
+		if p.s[i] == '\n' {
+			p.line++
+		}
+		i++
+	}
+	p.offset += i
+	p.s = p.s[i:len(p.s)]
+	if len(p.s) == 0 {
+		p.done = true
+	}
+}
+
+func (p *textParser) advance() {
+	// Skip whitespace
+	p.skipWhitespace()
+	if p.done {
+		return
+	}
+
+	// Start of non-whitespace
+	p.cur.err = nil
+	p.cur.offset, p.cur.line = p.offset, p.line
+	p.cur.unquoted = ""
+	switch p.s[0] {
+	case '<', '>', '{', '}', ':', '[', ']', ';', ',':
+		// Single symbol
+		p.cur.value, p.s = p.s[0:1], p.s[1:len(p.s)]
+	case '"', '\'':
+		// Quoted string
+		i := 1
+		for i < len(p.s) && p.s[i] != p.s[0] && p.s[i] != '\n' {
+			if p.s[i] == '\\' && i+1 < len(p.s) {
+				// skip escaped char
+				i++
+			}
+			i++
+		}
+		if i >= len(p.s) || p.s[i] != p.s[0] {
+			p.errorf("unmatched quote")
+			return
+		}
+		unq, err := unquoteC(p.s[1:i], rune(p.s[0]))
+		if err != nil {
+			p.errorf("invalid quoted string %s: %v", p.s[0:i+1], err)
+			return
+		}
+		p.cur.value, p.s = p.s[0:i+1], p.s[i+1:len(p.s)]
+		p.cur.unquoted = unq
+	default:
+		i := 0
+		for i < len(p.s) && isIdentOrNumberChar(p.s[i]) {
+			i++
+		}
+		if i == 0 {
+			p.errorf("unexpected byte %#x", p.s[0])
+			return
+		}
+		p.cur.value, p.s = p.s[0:i], p.s[i:len(p.s)]
+	}
+	p.offset += len(p.cur.value)
+}
+
+var (
+	errBadUTF8 = errors.New("proto: bad UTF-8")
+	errBadHex  = errors.New("proto: bad hexadecimal")
+)
+
+func unquoteC(s string, quote rune) (string, error) {
+	// This is based on C++'s tokenizer.cc.
+	// Despite its name, this is *not* parsing C syntax.
+	// For instance, "\0" is an invalid quoted string.
+
+	// Avoid allocation in trivial cases.
+	simple := true
+	for _, r := range s {
+		if r == '\\' || r == quote {
+			simple = false
+			break
+		}
+	}
+	if simple {
+		return s, nil
+	}
+
+	buf := make([]byte, 0, 3*len(s)/2)
+	for len(s) > 0 {
+		r, n := utf8.DecodeRuneInString(s)
+		if r == utf8.RuneError && n == 1 {
+			return "", errBadUTF8
+		}
+		s = s[n:]
+		if r != '\\' {
+			if r < utf8.RuneSelf {
+				buf = append(buf, byte(r))
+			} else {
+				buf = append(buf, string(r)...)
+			}
+			continue
+		}
+
+		ch, tail, err := unescape(s)
+		if err != nil {
+			return "", err
+		}
+		buf = append(buf, ch...)
+		s = tail
+	}
+	return string(buf), nil
+}
+
+func unescape(s string) (ch string, tail string, err error) {
+	r, n := utf8.DecodeRuneInString(s)
+	if r == utf8.RuneError && n == 1 {
+		return "", "", errBadUTF8
+	}
+	s = s[n:]
+	switch r {
+	case 'a':
+		return "\a", s, nil
+	case 'b':
+		return "\b", s, nil
+	case 'f':
+		return "\f", s, nil
+	case 'n':
+		return "\n", s, nil
+	case 'r':
+		return "\r", s, nil
+	case 't':
+		return "\t", s, nil
+	case 'v':
+		return "\v", s, nil
+	case '?':
+		return "?", s, nil // trigraph workaround
+	case '\'', '"', '\\':
+		return string(r), s, nil
+	case '0', '1', '2', '3', '4', '5', '6', '7', 'x', 'X':
+		if len(s) < 2 {
+			return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
+		}
+		base := 8
+		ss := s[:2]
+		s = s[2:]
+		if r == 'x' || r == 'X' {
+			base = 16
+		} else {
+			ss = string(r) + ss
+		}
+		i, err := strconv.ParseUint(ss, base, 8)
+		if err != nil {
+			return "", "", err
+		}
+		return string([]byte{byte(i)}), s, nil
+	case 'u', 'U':
+		n := 4
+		if r == 'U' {
+			n = 8
+		}
+		if len(s) < n {
+			return "", "", fmt.Errorf(`\%c requires %d digits`, r, n)
+		}
+
+		bs := make([]byte, n/2)
+		for i := 0; i < n; i += 2 {
+			a, ok1 := unhex(s[i])
+			b, ok2 := unhex(s[i+1])
+			if !ok1 || !ok2 {
+				return "", "", errBadHex
+			}
+			bs[i/2] = a<<4 | b
+		}
+		s = s[n:]
+		return string(bs), s, nil
+	}
+	return "", "", fmt.Errorf(`unknown escape \%c`, r)
+}
+
+// Adapted from src/pkg/strconv/quote.go.
+func unhex(b byte) (v byte, ok bool) {
+	switch {
+	case '0' <= b && b <= '9':
+		return b - '0', true
+	case 'a' <= b && b <= 'f':
+		return b - 'a' + 10, true
+	case 'A' <= b && b <= 'F':
+		return b - 'A' + 10, true
+	}
+	return 0, false
+}
+
+// Back off the parser by one token. Can only be done between calls to next().
+// It makes the next advance() a no-op.
+func (p *textParser) back() { p.backed = true }
+
+// Advances the parser and returns the new current token.
+func (p *textParser) next() *token {
+	if p.backed || p.done {
+		p.backed = false
+		return &p.cur
+	}
+	p.advance()
+	if p.done {
+		p.cur.value = ""
+	} else if len(p.cur.value) > 0 && p.cur.value[0] == '"' {
+		// Look for multiple quoted strings separated by whitespace,
+		// and concatenate them.
+		cat := p.cur
+		for {
+			p.skipWhitespace()
+			if p.done || p.s[0] != '"' {
+				break
+			}
+			p.advance()
+			if p.cur.err != nil {
+				return &p.cur
+			}
+			cat.value += " " + p.cur.value
+			cat.unquoted += p.cur.unquoted
+		}
+		p.done = false // parser may have seen EOF, but we want to return cat
+		p.cur = cat
+	}
+	return &p.cur
+}
+
+func (p *textParser) consumeToken(s string) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != s {
+		p.back()
+		return p.errorf("expected %q, found %q", s, tok.value)
+	}
+	return nil
+}
+
+// Return a RequiredNotSetError indicating which required field was not set.
+func (p *textParser) missingRequiredFieldError(sv reflect.Value) *RequiredNotSetError {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < st.NumField(); i++ {
+		if !isNil(sv.Field(i)) {
+			continue
+		}
+
+		props := sprops.Prop[i]
+		if props.Required {
+			return &RequiredNotSetError{fmt.Sprintf("%v.%v", st, props.OrigName)}
+		}
+	}
+	return &RequiredNotSetError{fmt.Sprintf("%v.<unknown field name>", st)} // should not happen
+}
+
+// Returns the index in the struct for the named field, as well as the parsed tag properties.
+func structFieldByName(sprops *StructProperties, name string) (int, *Properties, bool) {
+	i, ok := sprops.decoderOrigNames[name]
+	if ok {
+		return i, sprops.Prop[i], true
+	}
+	return -1, nil, false
+}
+
+// Consume a ':' from the input stream (if the next token is a colon),
+// returning an error if a colon is needed but not present.
+func (p *textParser) checkForColon(props *Properties, typ reflect.Type) *ParseError {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ":" {
+		// Colon is optional when the field is a group or message.
+		needColon := true
+		switch props.Wire {
+		case "group":
+			needColon = false
+		case "bytes":
+			// A "bytes" field is either a message, a string, or a repeated field;
+			// those three become *T, *string and []T respectively, so we can check for
+			// this field being a pointer to a non-string.
+			if typ.Kind() == reflect.Ptr {
+				// *T or *string
+				if typ.Elem().Kind() == reflect.String {
+					break
+				}
+			} else if typ.Kind() == reflect.Slice {
+				// []T or []*T
+				if typ.Elem().Kind() != reflect.Ptr {
+					break
+				}
+			} else if typ.Kind() == reflect.String {
+				// The proto3 exception is for a string field,
+				// which requires a colon.
+				break
+			}
+			needColon = false
+		}
+		if needColon {
+			return p.errorf("expected ':', found %q", tok.value)
+		}
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	reqCount := sprops.reqCount
+	var reqFieldErr error
+	fieldSet := make(map[string]bool)
+	// A struct is a sequence of "name: value", terminated by one of
+	// '>' or '}', or the end of the input.  A name may also be
+	// "[extension]".
+	for {
+		tok := p.next()
+		if tok.err != nil {
+			return tok.err
+		}
+		if tok.value == terminator {
+			break
+		}
+		if tok.value == "[" {
+			// Looks like an extension.
+			//
+			// TODO: Check whether we need to handle
+			// namespace rooted names (e.g. ".something.Foo").
+			tok = p.next()
+			if tok.err != nil {
+				return tok.err
+			}
+			var desc *ExtensionDesc
+			// This could be faster, but it's functional.
+			// TODO: Do something smarter than a linear scan.
+			for _, d := range RegisteredExtensions(reflect.New(st).Interface().(Message)) {
+				if d.Name == tok.value {
+					desc = d
+					break
+				}
+			}
+			if desc == nil {
+				return p.errorf("unrecognized extension %q", tok.value)
+			}
+			// Check the extension terminator.
+			tok = p.next()
+			if tok.err != nil {
+				return tok.err
+			}
+			if tok.value != "]" {
+				return p.errorf("unrecognized extension terminator %q", tok.value)
+			}
+
+			props := &Properties{}
+			props.Parse(desc.Tag)
+
+			typ := reflect.TypeOf(desc.ExtensionType)
+			if err := p.checkForColon(props, typ); err != nil {
+				return err
+			}
+
+			rep := desc.repeated()
+
+			// Read the extension structure, and set it in
+			// the value we're constructing.
+			var ext reflect.Value
+			if !rep {
+				ext = reflect.New(typ).Elem()
+			} else {
+				ext = reflect.New(typ.Elem()).Elem()
+			}
+			if err := p.readAny(ext, props); err != nil {
+				if _, ok := err.(*RequiredNotSetError); !ok {
+					return err
+				}
+				reqFieldErr = err
+			}
+			ep := sv.Addr().Interface().(extendableProto)
+			if !rep {
+				SetExtension(ep, desc, ext.Interface())
+			} else {
+				old, err := GetExtension(ep, desc)
+				var sl reflect.Value
+				if err == nil {
+					sl = reflect.ValueOf(old) // existing slice
+				} else {
+					sl = reflect.MakeSlice(typ, 0, 1)
+				}
+				sl = reflect.Append(sl, ext)
+				SetExtension(ep, desc, sl.Interface())
+			}
+			if err := p.consumeOptionalSeparator(); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// This is a normal, non-extension field.
+		name := tok.value
+		var dst reflect.Value
+		fi, props, ok := structFieldByName(sprops, name)
+		if ok {
+			dst = sv.Field(fi)
+		} else if oop, ok := sprops.OneofTypes[name]; ok {
+			// It is a oneof.
+			props = oop.Prop
+			nv := reflect.New(oop.Type.Elem())
+			dst = nv.Elem().Field(0)
+			sv.Field(oop.Field).Set(nv)
+		}
+		if !dst.IsValid() {
+			return p.errorf("unknown field name %q in %v", name, st)
+		}
+
+		if dst.Kind() == reflect.Map {
+			// Consume any colon.
+			if err := p.checkForColon(props, dst.Type()); err != nil {
+				return err
+			}
+
+			// Construct the map if it doesn't already exist.
+			if dst.IsNil() {
+				dst.Set(reflect.MakeMap(dst.Type()))
+			}
+			key := reflect.New(dst.Type().Key()).Elem()
+			val := reflect.New(dst.Type().Elem()).Elem()
+
+			// The map entry should be this sequence of tokens:
+			//	< key : KEY value : VALUE >
+			// Technically the "key" and "value" could come in any order,
+			// but in practice they won't.
+
+			tok := p.next()
+			var terminator string
+			switch tok.value {
+			case "<":
+				terminator = ">"
+			case "{":
+				terminator = "}"
+			default:
+				return p.errorf("expected '{' or '<', found %q", tok.value)
+			}
+			if err := p.consumeToken("key"); err != nil {
+				return err
+			}
+			if err := p.consumeToken(":"); err != nil {
+				return err
+			}
+			if err := p.readAny(key, props.mkeyprop); err != nil {
+				return err
+			}
+			if err := p.consumeOptionalSeparator(); err != nil {
+				return err
+			}
+			if err := p.consumeToken("value"); err != nil {
+				return err
+			}
+			if err := p.checkForColon(props.mvalprop, dst.Type().Elem()); err != nil {
+				return err
+			}
+			if err := p.readAny(val, props.mvalprop); err != nil {
+				return err
+			}
+			if err := p.consumeOptionalSeparator(); err != nil {
+				return err
+			}
+			if err := p.consumeToken(terminator); err != nil {
+				return err
+			}
+
+			dst.SetMapIndex(key, val)
+			continue
+		}
+
+		// Check that it's not already set if it's not a repeated field.
+		if !props.Repeated && fieldSet[name] {
+			return p.errorf("non-repeated field %q was repeated", name)
+		}
+
+		if err := p.checkForColon(props, dst.Type()); err != nil {
+			return err
+		}
+
+		// Parse into the field.
+		fieldSet[name] = true
+		if err := p.readAny(dst, props); err != nil {
+			if _, ok := err.(*RequiredNotSetError); !ok {
+				return err
+			}
+			reqFieldErr = err
+		} else if props.Required {
+			reqCount--
+		}
+
+		if err := p.consumeOptionalSeparator(); err != nil {
+			return err
+		}
+
+	}
+
+	if reqCount > 0 {
+		return p.missingRequiredFieldError(sv)
+	}
+	return reqFieldErr
+}
+
+// consumeOptionalSeparator consumes an optional semicolon or comma.
+// It is used in readStruct to provide backward compatibility.
+func (p *textParser) consumeOptionalSeparator() error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ";" && tok.value != "," {
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readAny(v reflect.Value, props *Properties) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value == "" {
+		return p.errorf("unexpected EOF")
+	}
+
+	switch fv := v; fv.Kind() {
+	case reflect.Slice:
+		at := v.Type()
+		if at.Elem().Kind() == reflect.Uint8 {
+			// Special case for []byte
+			if tok.value[0] != '"' && tok.value[0] != '\'' {
+				// Deliberately written out here, as the error after
+				// this switch statement would write "invalid []byte: ...",
+				// which is not as user-friendly.
+				return p.errorf("invalid string: %v", tok.value)
+			}
+			bytes := []byte(tok.unquoted)
+			fv.Set(reflect.ValueOf(bytes))
+			return nil
+		}
+		// Repeated field. May already exist.
+		flen := fv.Len()
+		if flen == fv.Cap() {
+			nav := reflect.MakeSlice(at, flen, 2*flen+1)
+			reflect.Copy(nav, fv)
+			fv.Set(nav)
+		}
+		fv.SetLen(flen + 1)
+
+		// Read one.
+		p.back()
+		return p.readAny(fv.Index(flen), props)
+	case reflect.Bool:
+		// Either "true", "false", 1 or 0.
+		switch tok.value {
+		case "true", "1":
+			fv.SetBool(true)
+			return nil
+		case "false", "0":
+			fv.SetBool(false)
+			return nil
+		}
+	case reflect.Float32, reflect.Float64:
+		v := tok.value
+		// Ignore 'f' for compatibility with output generated by C++, but don't
+		// remove 'f' when the value is "-inf" or "inf".
+		if strings.HasSuffix(v, "f") && tok.value != "-inf" && tok.value != "inf" {
+			v = v[:len(v)-1]
+		}
+		if f, err := strconv.ParseFloat(v, fv.Type().Bits()); err == nil {
+			fv.SetFloat(f)
+			return nil
+		}
+	case reflect.Int32:
+		if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+		if len(props.Enum) == 0 {
+			break
+		}
+		m, ok := enumValueMaps[props.Enum]
+		if !ok {
+			break
+		}
+		x, ok := m[tok.value]
+		if !ok {
+			break
+		}
+		fv.SetInt(int64(x))
+		return nil
+	case reflect.Int64:
+		if x, err := strconv.ParseInt(tok.value, 0, 64); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+	case reflect.Ptr:
+		// A basic field (indirected through pointer), or a repeated message/group
+		p.back()
+		fv.Set(reflect.New(fv.Type().Elem()))
+		return p.readAny(fv.Elem(), props)
+	case reflect.String:
+		if tok.value[0] == '"' || tok.value[0] == '\'' {
+			fv.SetString(tok.unquoted)
+			return nil
+		}
+	case reflect.Struct:
+		var terminator string
+		switch tok.value {
+		case "{":
+			terminator = "}"
+		case "<":
+			terminator = ">"
+		default:
+			return p.errorf("expected '{' or '<', found %q", tok.value)
+		}
+		// TODO: Handle nested messages which implement encoding.TextUnmarshaler.
+		return p.readStruct(fv, terminator)
+	case reflect.Uint32:
+		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
+			fv.SetUint(uint64(x))
+			return nil
+		}
+	case reflect.Uint64:
+		if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
+			fv.SetUint(x)
+			return nil
+		}
+	}
+	return p.errorf("invalid %v: %v", v.Type(), tok.value)
+}
+
+// UnmarshalText reads a protocol buffer in Text format. UnmarshalText resets pb
+// before starting to unmarshal, so any existing data in pb is always removed.
+// If a required field is not set and no other error occurs,
+// UnmarshalText returns *RequiredNotSetError.
+func UnmarshalText(s string, pb Message) error {
+	if um, ok := pb.(encoding.TextUnmarshaler); ok {
+		err := um.UnmarshalText([]byte(s))
+		return err
+	}
+	pb.Reset()
+	v := reflect.ValueOf(pb)
+	if pe := newTextParser(s).readStruct(v.Elem(), ""); pe != nil {
+		return pe
+	}
+	return nil
+}

vendor/github.com/gorilla/context/.travis.yml

@@ -0,0 +1,8 @@
+language: go
+sudo: false
+
+go:
+  - 1.3
+  - 1.4
+  - 1.5
+  - tip

vendor/github.com/gorilla/context/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 Rodrigo Moraes. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/context/README.md

@@ -0,0 +1,7 @@
+context
+=======
+[![Build Status](https://travis-ci.org/gorilla/context.png?branch=master)](https://travis-ci.org/gorilla/context)
+
+gorilla/context is a general purpose registry for global request variables.
+
+Read the full documentation here: http://www.gorillatoolkit.org/pkg/context

vendor/github.com/gorilla/context/context.go

@@ -0,0 +1,143 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context
+
+import (
+	"net/http"
+	"sync"
+	"time"
+)
+
+var (
+	mutex sync.RWMutex
+	data  = make(map[*http.Request]map[interface{}]interface{})
+	datat = make(map[*http.Request]int64)
+)
+
+// Set stores a value for a given key in a given request.
+func Set(r *http.Request, key, val interface{}) {
+	mutex.Lock()
+	if data[r] == nil {
+		data[r] = make(map[interface{}]interface{})
+		datat[r] = time.Now().Unix()
+	}
+	data[r][key] = val
+	mutex.Unlock()
+}
+
+// Get returns a value stored for a given key in a given request.
+func Get(r *http.Request, key interface{}) interface{} {
+	mutex.RLock()
+	if ctx := data[r]; ctx != nil {
+		value := ctx[key]
+		mutex.RUnlock()
+		return value
+	}
+	mutex.RUnlock()
+	return nil
+}
+
+// GetOk returns stored value and presence state like multi-value return of map access.
+func GetOk(r *http.Request, key interface{}) (interface{}, bool) {
+	mutex.RLock()
+	if _, ok := data[r]; ok {
+		value, ok := data[r][key]
+		mutex.RUnlock()
+		return value, ok
+	}
+	mutex.RUnlock()
+	return nil, false
+}
+
+// GetAll returns all stored values for the request as a map. Nil is returned for invalid requests.
+func GetAll(r *http.Request) map[interface{}]interface{} {
+	mutex.RLock()
+	if context, ok := data[r]; ok {
+		result := make(map[interface{}]interface{}, len(context))
+		for k, v := range context {
+			result[k] = v
+		}
+		mutex.RUnlock()
+		return result
+	}
+	mutex.RUnlock()
+	return nil
+}
+
+// GetAllOk returns all stored values for the request as a map and a boolean value that indicates if
+// the request was registered.
+func GetAllOk(r *http.Request) (map[interface{}]interface{}, bool) {
+	mutex.RLock()
+	context, ok := data[r]
+	result := make(map[interface{}]interface{}, len(context))
+	for k, v := range context {
+		result[k] = v
+	}
+	mutex.RUnlock()
+	return result, ok
+}
+
+// Delete removes a value stored for a given key in a given request.
+func Delete(r *http.Request, key interface{}) {
+	mutex.Lock()
+	if data[r] != nil {
+		delete(data[r], key)
+	}
+	mutex.Unlock()
+}
+
+// Clear removes all values stored for a given request.
+//
+// This is usually called by a handler wrapper to clean up request
+// variables at the end of a request lifetime. See ClearHandler().
+func Clear(r *http.Request) {
+	mutex.Lock()
+	clear(r)
+	mutex.Unlock()
+}
+
+// clear is Clear without the lock.
+func clear(r *http.Request) {
+	delete(data, r)
+	delete(datat, r)
+}
+
+// Purge removes request data stored for longer than maxAge, in seconds.
+// It returns the amount of requests removed.
+//
+// If maxAge <= 0, all request data is removed.
+//
+// This is only used for sanity check: in case context cleaning was not
+// properly set some request data can be kept forever, consuming an increasing
+// amount of memory. In case this is detected, Purge() must be called
+// periodically until the problem is fixed.
+func Purge(maxAge int) int {
+	mutex.Lock()
+	count := 0
+	if maxAge <= 0 {
+		count = len(data)
+		data = make(map[*http.Request]map[interface{}]interface{})
+		datat = make(map[*http.Request]int64)
+	} else {
+		min := time.Now().Unix() - int64(maxAge)
+		for r := range data {
+			if datat[r] < min {
+				clear(r)
+				count++
+			}
+		}
+	}
+	mutex.Unlock()
+	return count
+}
+
+// ClearHandler wraps an http.Handler and clears request values at the end
+// of a request lifetime.
+func ClearHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		defer Clear(r)
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/context/doc.go

@@ -0,0 +1,82 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package context stores values shared during a request lifetime.
+
+For example, a router can set variables extracted from the URL and later
+application handlers can access those values, or it can be used to store
+sessions values to be saved at the end of a request. There are several
+others common uses.
+
+The idea was posted by Brad Fitzpatrick to the go-nuts mailing list:
+
+	http://groups.google.com/group/golang-nuts/msg/e2d679d303aa5d53
+
+Here's the basic usage: first define the keys that you will need. The key
+type is interface{} so a key can be of any type that supports equality.
+Here we define a key using a custom int type to avoid name collisions:
+
+	package foo
+
+	import (
+		"github.com/gorilla/context"
+	)
+
+	type key int
+
+	const MyKey key = 0
+
+Then set a variable. Variables are bound to an http.Request object, so you
+need a request instance to set a value:
+
+	context.Set(r, MyKey, "bar")
+
+The application can later access the variable using the same key you provided:
+
+	func MyHandler(w http.ResponseWriter, r *http.Request) {
+		// val is "bar".
+		val := context.Get(r, foo.MyKey)
+
+		// returns ("bar", true)
+		val, ok := context.GetOk(r, foo.MyKey)
+		// ...
+	}
+
+And that's all about the basic usage. We discuss some other ideas below.
+
+Any type can be stored in the context. To enforce a given type, make the key
+private and wrap Get() and Set() to accept and return values of a specific
+type:
+
+	type key int
+
+	const mykey key = 0
+
+	// GetMyKey returns a value for this package from the request values.
+	func GetMyKey(r *http.Request) SomeType {
+		if rv := context.Get(r, mykey); rv != nil {
+			return rv.(SomeType)
+		}
+		return nil
+	}
+
+	// SetMyKey sets a value for this package in the request values.
+	func SetMyKey(r *http.Request, val SomeType) {
+		context.Set(r, mykey, val)
+	}
+
+Variables must be cleared at the end of a request, to remove all values
+that were stored. This can be done in an http.Handler, after a request was
+served. Just call Clear() passing the request:
+
+	context.Clear(r)
+
+...or use ClearHandler(), which conveniently wraps an http.Handler to clear
+variables at the end of a request lifetime.
+
+The Routers from the packages gorilla/mux and gorilla/pat call Clear()
+so if you are using either of them you don't need to clear the context manually.
+*/
+package context

vendor/github.com/gorilla/mux/.travis.yml

@@ -0,0 +1,8 @@
+language: go
+sudo: false
+
+go:
+  - 1.3
+  - 1.4
+  - 1.5
+  - tip

vendor/github.com/gorilla/mux/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 Rodrigo Moraes. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/mux/README.md

@@ -0,0 +1,235 @@
+mux
+===
+[![GoDoc](https://godoc.org/github.com/gorilla/mux?status.svg)](https://godoc.org/github.com/gorilla/mux)
+[![Build Status](https://travis-ci.org/gorilla/mux.png?branch=master)](https://travis-ci.org/gorilla/mux)
+
+Package gorilla/mux implements a request router and dispatcher.
+
+The name mux stands for "HTTP request multiplexer". Like the standard
+http.ServeMux, mux.Router matches incoming requests against a list of
+registered routes and calls a handler for the route that matches the URL
+or other conditions. The main features are:
+
+	* Requests can be matched based on URL host, path, path prefix, schemes,
+	  header and query values, HTTP methods or using custom matchers.
+	* URL hosts and paths can have variables with an optional regular
+	  expression.
+	* Registered URLs can be built, or "reversed", which helps maintaining
+	  references to resources.
+	* Routes can be used as subrouters: nested routes are only tested if the
+	  parent route matches. This is useful to define groups of routes that
+	  share common conditions like a host, a path prefix or other repeated
+	  attributes. As a bonus, this optimizes request matching.
+	* It implements the http.Handler interface so it is compatible with the
+	  standard http.ServeMux.
+
+Let's start registering a couple of URL paths and handlers:
+
+	func main() {
+		r := mux.NewRouter()
+		r.HandleFunc("/", HomeHandler)
+		r.HandleFunc("/products", ProductsHandler)
+		r.HandleFunc("/articles", ArticlesHandler)
+		http.Handle("/", r)
+	}
+
+Here we register three routes mapping URL paths to handlers. This is
+equivalent to how http.HandleFunc() works: if an incoming request URL matches
+one of the paths, the corresponding handler is called passing
+(http.ResponseWriter, *http.Request) as parameters.
+
+Paths can have variables. They are defined using the format {name} or
+{name:pattern}. If a regular expression pattern is not defined, the matched
+variable will be anything until the next slash. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/products/{key}", ProductHandler)
+	r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+
+The names are used to create a map of route variables which can be retrieved
+calling mux.Vars():
+
+	vars := mux.Vars(request)
+	category := vars["category"]
+
+And this is all you need to know about the basic usage. More advanced options
+are explained below.
+
+Routes can also be restricted to a domain or subdomain. Just define a host
+pattern to be matched. They can also have variables:
+
+	r := mux.NewRouter()
+	// Only matches if domain is "www.example.com".
+	r.Host("www.example.com")
+	// Matches a dynamic subdomain.
+	r.Host("{subdomain:[a-z]+}.domain.com")
+
+There are several other matchers that can be added. To match path prefixes:
+
+	r.PathPrefix("/products/")
+
+...or HTTP methods:
+
+	r.Methods("GET", "POST")
+
+...or URL schemes:
+
+	r.Schemes("https")
+
+...or header values:
+
+	r.Headers("X-Requested-With", "XMLHttpRequest")
+
+...or query values:
+
+	r.Queries("key", "value")
+
+...or to use a custom matcher function:
+
+	r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+		return r.ProtoMajor == 0
+	})
+
+...and finally, it is possible to combine several matchers in a single route:
+
+	r.HandleFunc("/products", ProductsHandler).
+	  Host("www.example.com").
+	  Methods("GET").
+	  Schemes("http")
+
+Setting the same matching conditions again and again can be boring, so we have
+a way to group several routes that share the same requirements.
+We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the
+host is `www.example.com`. Create a route for that host and get a "subrouter"
+from it:
+
+	r := mux.NewRouter()
+	s := r.Host("www.example.com").Subrouter()
+
+Then register routes in the subrouter:
+
+	s.HandleFunc("/products/", ProductsHandler)
+	s.HandleFunc("/products/{key}", ProductHandler)
+	s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+
+The three URL paths we registered above will only be tested if the domain is
+`www.example.com`, because the subrouter is tested first. This is not
+only convenient, but also optimizes request matching. You can create
+subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define
+subrouters in a central place and then parts of the app can register its
+paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix,
+the inner routes use it as base for their paths:
+
+	r := mux.NewRouter()
+	s := r.PathPrefix("/products").Subrouter()
+	// "/products/"
+	s.HandleFunc("/", ProductsHandler)
+	// "/products/{key}/"
+	s.HandleFunc("/{key}/", ProductHandler)
+	// "/products/{key}/details"
+	s.HandleFunc("/{key}/details", ProductDetailsHandler)
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built,
+or "reversed". We define a name calling Name() on a route. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+	  Name("article")
+
+To build a URL, get the route and call the URL() method, passing a sequence of
+key/value pairs for the route variables. For the previous route, we would do:
+
+	url, err := r.Get("article").URL("category", "technology", "id", "42")
+
+...and the result will be a url.URL with the following path:
+
+	"/articles/technology/42"
+
+This also works for host variables:
+
+	r := mux.NewRouter()
+	r.Host("{subdomain}.domain.com").
+	  Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// url.String() will be "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+
+All variables defined in the route are required, and their values must
+conform to the corresponding patterns. These requirements guarantee that a
+generated URL will always match a registered route -- the only exception is
+for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+	r.HeadersRegexp("Content-Type", "application/(text|json)")
+
+...and the route will match both requests with a Content-Type of `application/json` as well as
+`application/text`
+
+There's also a way to build only the URL host or path for a route:
+use the methods URLHost() or URLPath() instead. For the previous route,
+we would do:
+
+	// "http://news.domain.com/"
+	host, err := r.Get("article").URLHost("subdomain", "news")
+
+	// "/articles/technology/42"
+	path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+
+And if you use subrouters, host and path defined separately can be built
+as well:
+
+	r := mux.NewRouter()
+	s := r.Host("{subdomain}.domain.com").Subrouter()
+	s.Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+
+## Full Example
+
+Here's a complete, runnable example of a small mux based server:
+
+```go
+package main
+
+import (
+	"net/http"
+
+	"github.com/gorilla/mux"
+)
+
+func YourHandler(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte("Gorilla!\n"))
+}
+
+func main() {
+	r := mux.NewRouter()
+	// Routes consist of a path and a handler function.
+	r.HandleFunc("/", YourHandler)
+
+	// Bind to a port and pass our router in
+	http.ListenAndServe(":8000", r)
+}
+```
+
+## License
+
+BSD licensed. See the LICENSE file for details.

vendor/github.com/gorilla/mux/doc.go

@@ -0,0 +1,206 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package gorilla/mux implements a request router and dispatcher.
+
+The name mux stands for "HTTP request multiplexer". Like the standard
+http.ServeMux, mux.Router matches incoming requests against a list of
+registered routes and calls a handler for the route that matches the URL
+or other conditions. The main features are:
+
+	* Requests can be matched based on URL host, path, path prefix, schemes,
+	  header and query values, HTTP methods or using custom matchers.
+	* URL hosts and paths can have variables with an optional regular
+	  expression.
+	* Registered URLs can be built, or "reversed", which helps maintaining
+	  references to resources.
+	* Routes can be used as subrouters: nested routes are only tested if the
+	  parent route matches. This is useful to define groups of routes that
+	  share common conditions like a host, a path prefix or other repeated
+	  attributes. As a bonus, this optimizes request matching.
+	* It implements the http.Handler interface so it is compatible with the
+	  standard http.ServeMux.
+
+Let's start registering a couple of URL paths and handlers:
+
+	func main() {
+		r := mux.NewRouter()
+		r.HandleFunc("/", HomeHandler)
+		r.HandleFunc("/products", ProductsHandler)
+		r.HandleFunc("/articles", ArticlesHandler)
+		http.Handle("/", r)
+	}
+
+Here we register three routes mapping URL paths to handlers. This is
+equivalent to how http.HandleFunc() works: if an incoming request URL matches
+one of the paths, the corresponding handler is called passing
+(http.ResponseWriter, *http.Request) as parameters.
+
+Paths can have variables. They are defined using the format {name} or
+{name:pattern}. If a regular expression pattern is not defined, the matched
+variable will be anything until the next slash. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/products/{key}", ProductHandler)
+	r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+
+The names are used to create a map of route variables which can be retrieved
+calling mux.Vars():
+
+	vars := mux.Vars(request)
+	category := vars["category"]
+
+And this is all you need to know about the basic usage. More advanced options
+are explained below.
+
+Routes can also be restricted to a domain or subdomain. Just define a host
+pattern to be matched. They can also have variables:
+
+	r := mux.NewRouter()
+	// Only matches if domain is "www.example.com".
+	r.Host("www.example.com")
+	// Matches a dynamic subdomain.
+	r.Host("{subdomain:[a-z]+}.domain.com")
+
+There are several other matchers that can be added. To match path prefixes:
+
+	r.PathPrefix("/products/")
+
+...or HTTP methods:
+
+	r.Methods("GET", "POST")
+
+...or URL schemes:
+
+	r.Schemes("https")
+
+...or header values:
+
+	r.Headers("X-Requested-With", "XMLHttpRequest")
+
+...or query values:
+
+	r.Queries("key", "value")
+
+...or to use a custom matcher function:
+
+	r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+		return r.ProtoMajor == 0
+	})
+
+...and finally, it is possible to combine several matchers in a single route:
+
+	r.HandleFunc("/products", ProductsHandler).
+	  Host("www.example.com").
+	  Methods("GET").
+	  Schemes("http")
+
+Setting the same matching conditions again and again can be boring, so we have
+a way to group several routes that share the same requirements.
+We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the
+host is "www.example.com". Create a route for that host and get a "subrouter"
+from it:
+
+	r := mux.NewRouter()
+	s := r.Host("www.example.com").Subrouter()
+
+Then register routes in the subrouter:
+
+	s.HandleFunc("/products/", ProductsHandler)
+	s.HandleFunc("/products/{key}", ProductHandler)
+	s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+
+The three URL paths we registered above will only be tested if the domain is
+"www.example.com", because the subrouter is tested first. This is not
+only convenient, but also optimizes request matching. You can create
+subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define
+subrouters in a central place and then parts of the app can register its
+paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix,
+the inner routes use it as base for their paths:
+
+	r := mux.NewRouter()
+	s := r.PathPrefix("/products").Subrouter()
+	// "/products/"
+	s.HandleFunc("/", ProductsHandler)
+	// "/products/{key}/"
+	s.HandleFunc("/{key}/", ProductHandler)
+	// "/products/{key}/details"
+	s.HandleFunc("/{key}/details", ProductDetailsHandler)
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built,
+or "reversed". We define a name calling Name() on a route. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+	  Name("article")
+
+To build a URL, get the route and call the URL() method, passing a sequence of
+key/value pairs for the route variables. For the previous route, we would do:
+
+	url, err := r.Get("article").URL("category", "technology", "id", "42")
+
+...and the result will be a url.URL with the following path:
+
+	"/articles/technology/42"
+
+This also works for host variables:
+
+	r := mux.NewRouter()
+	r.Host("{subdomain}.domain.com").
+	  Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// url.String() will be "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+
+All variables defined in the route are required, and their values must
+conform to the corresponding patterns. These requirements guarantee that a
+generated URL will always match a registered route -- the only exception is
+for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+	r.HeadersRegexp("Content-Type", "application/(text|json)")
+
+...and the route will match both requests with a Content-Type of `application/json` as well as
+`application/text`
+
+There's also a way to build only the URL host or path for a route:
+use the methods URLHost() or URLPath() instead. For the previous route,
+we would do:
+
+	// "http://news.domain.com/"
+	host, err := r.Get("article").URLHost("subdomain", "news")
+
+	// "/articles/technology/42"
+	path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+
+And if you use subrouters, host and path defined separately can be built
+as well:
+
+	r := mux.NewRouter()
+	s := r.Host("{subdomain}.domain.com").Subrouter()
+	s.Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+*/
+package mux

vendor/github.com/gorilla/mux/mux.go

@@ -0,0 +1,469 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"path"
+	"regexp"
+
+	"github.com/gorilla/context"
+)
+
+// NewRouter returns a new router instance.
+func NewRouter() *Router {
+	return &Router{namedRoutes: make(map[string]*Route), KeepContext: false}
+}
+
+// Router registers routes to be matched and dispatches a handler.
+//
+// It implements the http.Handler interface, so it can be registered to serve
+// requests:
+//
+//     var router = mux.NewRouter()
+//
+//     func main() {
+//         http.Handle("/", router)
+//     }
+//
+// Or, for Google App Engine, register it in a init() function:
+//
+//     func init() {
+//         http.Handle("/", router)
+//     }
+//
+// This will send all incoming requests to the router.
+type Router struct {
+	// Configurable Handler to be used when no route matches.
+	NotFoundHandler http.Handler
+	// Parent route, if this is a subrouter.
+	parent parentRoute
+	// Routes to be matched, in order.
+	routes []*Route
+	// Routes by name for URL building.
+	namedRoutes map[string]*Route
+	// See Router.StrictSlash(). This defines the flag for new routes.
+	strictSlash bool
+	// If true, do not clear the request context after handling the request
+	KeepContext bool
+}
+
+// Match matches registered routes against the request.
+func (r *Router) Match(req *http.Request, match *RouteMatch) bool {
+	for _, route := range r.routes {
+		if route.Match(req, match) {
+			return true
+		}
+	}
+	return false
+}
+
+// ServeHTTP dispatches the handler registered in the matched route.
+//
+// When there is a match, the route variables can be retrieved calling
+// mux.Vars(request).
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	// Clean path to canonical form and redirect.
+	if p := cleanPath(req.URL.Path); p != req.URL.Path {
+
+		// Added 3 lines (Philip Schlump) - It was droping the query string and #whatever from query.
+		// This matches with fix in go 1.2 r.c. 4 for same problem.  Go Issue:
+		// http://code.google.com/p/go/issues/detail?id=5252
+		url := *req.URL
+		url.Path = p
+		p = url.String()
+
+		w.Header().Set("Location", p)
+		w.WriteHeader(http.StatusMovedPermanently)
+		return
+	}
+	var match RouteMatch
+	var handler http.Handler
+	if r.Match(req, &match) {
+		handler = match.Handler
+		setVars(req, match.Vars)
+		setCurrentRoute(req, match.Route)
+	}
+	if handler == nil {
+		handler = r.NotFoundHandler
+		if handler == nil {
+			handler = http.NotFoundHandler()
+		}
+	}
+	if !r.KeepContext {
+		defer context.Clear(req)
+	}
+	handler.ServeHTTP(w, req)
+}
+
+// Get returns a route registered with the given name.
+func (r *Router) Get(name string) *Route {
+	return r.getNamedRoutes()[name]
+}
+
+// GetRoute returns a route registered with the given name. This method
+// was renamed to Get() and remains here for backwards compatibility.
+func (r *Router) GetRoute(name string) *Route {
+	return r.getNamedRoutes()[name]
+}
+
+// StrictSlash defines the trailing slash behavior for new routes. The initial
+// value is false.
+//
+// When true, if the route path is "/path/", accessing "/path" will redirect
+// to the former and vice versa. In other words, your application will always
+// see the path as specified in the route.
+//
+// When false, if the route path is "/path", accessing "/path/" will not match
+// this route and vice versa.
+//
+// Special case: when a route sets a path prefix using the PathPrefix() method,
+// strict slash is ignored for that route because the redirect behavior can't
+// be determined from a prefix alone. However, any subrouters created from that
+// route inherit the original StrictSlash setting.
+func (r *Router) StrictSlash(value bool) *Router {
+	r.strictSlash = value
+	return r
+}
+
+// ----------------------------------------------------------------------------
+// parentRoute
+// ----------------------------------------------------------------------------
+
+// getNamedRoutes returns the map where named routes are registered.
+func (r *Router) getNamedRoutes() map[string]*Route {
+	if r.namedRoutes == nil {
+		if r.parent != nil {
+			r.namedRoutes = r.parent.getNamedRoutes()
+		} else {
+			r.namedRoutes = make(map[string]*Route)
+		}
+	}
+	return r.namedRoutes
+}
+
+// getRegexpGroup returns regexp definitions from the parent route, if any.
+func (r *Router) getRegexpGroup() *routeRegexpGroup {
+	if r.parent != nil {
+		return r.parent.getRegexpGroup()
+	}
+	return nil
+}
+
+func (r *Router) buildVars(m map[string]string) map[string]string {
+	if r.parent != nil {
+		m = r.parent.buildVars(m)
+	}
+	return m
+}
+
+// ----------------------------------------------------------------------------
+// Route factories
+// ----------------------------------------------------------------------------
+
+// NewRoute registers an empty route.
+func (r *Router) NewRoute() *Route {
+	route := &Route{parent: r, strictSlash: r.strictSlash}
+	r.routes = append(r.routes, route)
+	return route
+}
+
+// Handle registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.Handler().
+func (r *Router) Handle(path string, handler http.Handler) *Route {
+	return r.NewRoute().Path(path).Handler(handler)
+}
+
+// HandleFunc registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.HandlerFunc().
+func (r *Router) HandleFunc(path string, f func(http.ResponseWriter,
+	*http.Request)) *Route {
+	return r.NewRoute().Path(path).HandlerFunc(f)
+}
+
+// Headers registers a new route with a matcher for request header values.
+// See Route.Headers().
+func (r *Router) Headers(pairs ...string) *Route {
+	return r.NewRoute().Headers(pairs...)
+}
+
+// Host registers a new route with a matcher for the URL host.
+// See Route.Host().
+func (r *Router) Host(tpl string) *Route {
+	return r.NewRoute().Host(tpl)
+}
+
+// MatcherFunc registers a new route with a custom matcher function.
+// See Route.MatcherFunc().
+func (r *Router) MatcherFunc(f MatcherFunc) *Route {
+	return r.NewRoute().MatcherFunc(f)
+}
+
+// Methods registers a new route with a matcher for HTTP methods.
+// See Route.Methods().
+func (r *Router) Methods(methods ...string) *Route {
+	return r.NewRoute().Methods(methods...)
+}
+
+// Path registers a new route with a matcher for the URL path.
+// See Route.Path().
+func (r *Router) Path(tpl string) *Route {
+	return r.NewRoute().Path(tpl)
+}
+
+// PathPrefix registers a new route with a matcher for the URL path prefix.
+// See Route.PathPrefix().
+func (r *Router) PathPrefix(tpl string) *Route {
+	return r.NewRoute().PathPrefix(tpl)
+}
+
+// Queries registers a new route with a matcher for URL query values.
+// See Route.Queries().
+func (r *Router) Queries(pairs ...string) *Route {
+	return r.NewRoute().Queries(pairs...)
+}
+
+// Schemes registers a new route with a matcher for URL schemes.
+// See Route.Schemes().
+func (r *Router) Schemes(schemes ...string) *Route {
+	return r.NewRoute().Schemes(schemes...)
+}
+
+// BuildVars registers a new route with a custom function for modifying
+// route variables before building a URL.
+func (r *Router) BuildVarsFunc(f BuildVarsFunc) *Route {
+	return r.NewRoute().BuildVarsFunc(f)
+}
+
+// Walk walks the router and all its sub-routers, calling walkFn for each route
+// in the tree. The routes are walked in the order they were added. Sub-routers
+// are explored depth-first.
+func (r *Router) Walk(walkFn WalkFunc) error {
+	return r.walk(walkFn, []*Route{})
+}
+
+// SkipRouter is used as a return value from WalkFuncs to indicate that the
+// router that walk is about to descend down to should be skipped.
+var SkipRouter = errors.New("skip this router")
+
+// WalkFunc is the type of the function called for each route visited by Walk.
+// At every invocation, it is given the current route, and the current router,
+// and a list of ancestor routes that lead to the current route.
+type WalkFunc func(route *Route, router *Router, ancestors []*Route) error
+
+func (r *Router) walk(walkFn WalkFunc, ancestors []*Route) error {
+	for _, t := range r.routes {
+		if t.regexp == nil || t.regexp.path == nil || t.regexp.path.template == "" {
+			continue
+		}
+
+		err := walkFn(t, r, ancestors)
+		if err == SkipRouter {
+			continue
+		}
+		for _, sr := range t.matchers {
+			if h, ok := sr.(*Router); ok {
+				err := h.walk(walkFn, ancestors)
+				if err != nil {
+					return err
+				}
+			}
+		}
+		if h, ok := t.handler.(*Router); ok {
+			ancestors = append(ancestors, t)
+			err := h.walk(walkFn, ancestors)
+			if err != nil {
+				return err
+			}
+			ancestors = ancestors[:len(ancestors)-1]
+		}
+	}
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+// Context
+// ----------------------------------------------------------------------------
+
+// RouteMatch stores information about a matched route.
+type RouteMatch struct {
+	Route   *Route
+	Handler http.Handler
+	Vars    map[string]string
+}
+
+type contextKey int
+
+const (
+	varsKey contextKey = iota
+	routeKey
+)
+
+// Vars returns the route variables for the current request, if any.
+func Vars(r *http.Request) map[string]string {
+	if rv := context.Get(r, varsKey); rv != nil {
+		return rv.(map[string]string)
+	}
+	return nil
+}
+
+// CurrentRoute returns the matched route for the current request, if any.
+// This only works when called inside the handler of the matched route
+// because the matched route is stored in the request context which is cleared
+// after the handler returns, unless the KeepContext option is set on the
+// Router.
+func CurrentRoute(r *http.Request) *Route {
+	if rv := context.Get(r, routeKey); rv != nil {
+		return rv.(*Route)
+	}
+	return nil
+}
+
+func setVars(r *http.Request, val interface{}) {
+	context.Set(r, varsKey, val)
+}
+
+func setCurrentRoute(r *http.Request, val interface{}) {
+	context.Set(r, routeKey, val)
+}
+
+// ----------------------------------------------------------------------------
+// Helpers
+// ----------------------------------------------------------------------------
+
+// cleanPath returns the canonical path for p, eliminating . and .. elements.
+// Borrowed from the net/http package.
+func cleanPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root;
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		np += "/"
+	}
+	return np
+}
+
+// uniqueVars returns an error if two slices contain duplicated strings.
+func uniqueVars(s1, s2 []string) error {
+	for _, v1 := range s1 {
+		for _, v2 := range s2 {
+			if v1 == v2 {
+				return fmt.Errorf("mux: duplicated route variable %q", v2)
+			}
+		}
+	}
+	return nil
+}
+
+func checkPairs(pairs ...string) (int, error) {
+	length := len(pairs)
+	if length%2 != 0 {
+		return length, fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+	}
+	return length, nil
+}
+
+// mapFromPairs converts variadic string parameters to a string map.
+func mapFromPairsToString(pairs ...string) (map[string]string, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]string, length/2)
+	for i := 0; i < length; i += 2 {
+		m[pairs[i]] = pairs[i+1]
+	}
+	return m, nil
+}
+
+func mapFromPairsToRegex(pairs ...string) (map[string]*regexp.Regexp, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]*regexp.Regexp, length/2)
+	for i := 0; i < length; i += 2 {
+		regex, err := regexp.Compile(pairs[i+1])
+		if err != nil {
+			return nil, err
+		}
+		m[pairs[i]] = regex
+	}
+	return m, nil
+}
+
+// matchInArray returns true if the given string value is in the array.
+func matchInArray(arr []string, value string) bool {
+	for _, v := range arr {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+// matchMapWithString returns true if the given key/value pairs exist in a given map.
+func matchMapWithString(toCheck map[string]string, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != "" {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v == value {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// matchMapWithRegex returns true if the given key/value pairs exist in a given map compiled against
+// the given regex
+func matchMapWithRegex(toCheck map[string]*regexp.Regexp, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != nil {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v.MatchString(value) {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}

vendor/github.com/gorilla/mux/regexp.go

@@ -0,0 +1,317 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+// newRouteRegexp parses a route template and returns a routeRegexp,
+// used to match a host, a path or a query string.
+//
+// It will extract named variables, assemble a regexp to be matched, create
+// a "reverse" template to build URLs and compile regexps to validate variable
+// values used in URL building.
+//
+// Previously we accepted only Python-like identifiers for variable
+// names ([a-zA-Z_][a-zA-Z0-9_]*), but currently the only restriction is that
+// name and pattern can't be empty, and names can't contain a colon.
+func newRouteRegexp(tpl string, matchHost, matchPrefix, matchQuery, strictSlash bool) (*routeRegexp, error) {
+	// Check if it is well-formed.
+	idxs, errBraces := braceIndices(tpl)
+	if errBraces != nil {
+		return nil, errBraces
+	}
+	// Backup the original.
+	template := tpl
+	// Now let's parse it.
+	defaultPattern := "[^/]+"
+	if matchQuery {
+		defaultPattern = "[^?&]*"
+	} else if matchHost {
+		defaultPattern = "[^.]+"
+		matchPrefix = false
+	}
+	// Only match strict slash if not matching
+	if matchPrefix || matchHost || matchQuery {
+		strictSlash = false
+	}
+	// Set a flag for strictSlash.
+	endSlash := false
+	if strictSlash && strings.HasSuffix(tpl, "/") {
+		tpl = tpl[:len(tpl)-1]
+		endSlash = true
+	}
+	varsN := make([]string, len(idxs)/2)
+	varsR := make([]*regexp.Regexp, len(idxs)/2)
+	pattern := bytes.NewBufferString("")
+	pattern.WriteByte('^')
+	reverse := bytes.NewBufferString("")
+	var end int
+	var err error
+	for i := 0; i < len(idxs); i += 2 {
+		// Set all values we are interested in.
+		raw := tpl[end:idxs[i]]
+		end = idxs[i+1]
+		parts := strings.SplitN(tpl[idxs[i]+1:end-1], ":", 2)
+		name := parts[0]
+		patt := defaultPattern
+		if len(parts) == 2 {
+			patt = parts[1]
+		}
+		// Name or pattern can't be empty.
+		if name == "" || patt == "" {
+			return nil, fmt.Errorf("mux: missing name or pattern in %q",
+				tpl[idxs[i]:end])
+		}
+		// Build the regexp pattern.
+		varIdx := i / 2
+		fmt.Fprintf(pattern, "%s(?P<%s>%s)", regexp.QuoteMeta(raw), varGroupName(varIdx), patt)
+		// Build the reverse template.
+		fmt.Fprintf(reverse, "%s%%s", raw)
+
+		// Append variable name and compiled pattern.
+		varsN[varIdx] = name
+		varsR[varIdx], err = regexp.Compile(fmt.Sprintf("^%s$", patt))
+		if err != nil {
+			return nil, err
+		}
+	}
+	// Add the remaining.
+	raw := tpl[end:]
+	pattern.WriteString(regexp.QuoteMeta(raw))
+	if strictSlash {
+		pattern.WriteString("[/]?")
+	}
+	if matchQuery {
+		// Add the default pattern if the query value is empty
+		if queryVal := strings.SplitN(template, "=", 2)[1]; queryVal == "" {
+			pattern.WriteString(defaultPattern)
+		}
+	}
+	if !matchPrefix {
+		pattern.WriteByte('$')
+	}
+	reverse.WriteString(raw)
+	if endSlash {
+		reverse.WriteByte('/')
+	}
+	// Compile full regexp.
+	reg, errCompile := regexp.Compile(pattern.String())
+	if errCompile != nil {
+		return nil, errCompile
+	}
+	// Done!
+	return &routeRegexp{
+		template:    template,
+		matchHost:   matchHost,
+		matchQuery:  matchQuery,
+		strictSlash: strictSlash,
+		regexp:      reg,
+		reverse:     reverse.String(),
+		varsN:       varsN,
+		varsR:       varsR,
+	}, nil
+}
+
+// routeRegexp stores a regexp to match a host or path and information to
+// collect and validate route variables.
+type routeRegexp struct {
+	// The unmodified template.
+	template string
+	// True for host match, false for path or query string match.
+	matchHost bool
+	// True for query string match, false for path and host match.
+	matchQuery bool
+	// The strictSlash value defined on the route, but disabled if PathPrefix was used.
+	strictSlash bool
+	// Expanded regexp.
+	regexp *regexp.Regexp
+	// Reverse template.
+	reverse string
+	// Variable names.
+	varsN []string
+	// Variable regexps (validators).
+	varsR []*regexp.Regexp
+}
+
+// Match matches the regexp against the URL host or path.
+func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
+	if !r.matchHost {
+		if r.matchQuery {
+			return r.matchQueryString(req)
+		} else {
+			return r.regexp.MatchString(req.URL.Path)
+		}
+	}
+	return r.regexp.MatchString(getHost(req))
+}
+
+// url builds a URL part using the given values.
+func (r *routeRegexp) url(values map[string]string) (string, error) {
+	urlValues := make([]interface{}, len(r.varsN))
+	for k, v := range r.varsN {
+		value, ok := values[v]
+		if !ok {
+			return "", fmt.Errorf("mux: missing route variable %q", v)
+		}
+		urlValues[k] = value
+	}
+	rv := fmt.Sprintf(r.reverse, urlValues...)
+	if !r.regexp.MatchString(rv) {
+		// The URL is checked against the full regexp, instead of checking
+		// individual variables. This is faster but to provide a good error
+		// message, we check individual regexps if the URL doesn't match.
+		for k, v := range r.varsN {
+			if !r.varsR[k].MatchString(values[v]) {
+				return "", fmt.Errorf(
+					"mux: variable %q doesn't match, expected %q", values[v],
+					r.varsR[k].String())
+			}
+		}
+	}
+	return rv, nil
+}
+
+// getUrlQuery returns a single query parameter from a request URL.
+// For a URL with foo=bar&baz=ding, we return only the relevant key
+// value pair for the routeRegexp.
+func (r *routeRegexp) getUrlQuery(req *http.Request) string {
+	if !r.matchQuery {
+		return ""
+	}
+	templateKey := strings.SplitN(r.template, "=", 2)[0]
+	for key, vals := range req.URL.Query() {
+		if key == templateKey && len(vals) > 0 {
+			return key + "=" + vals[0]
+		}
+	}
+	return ""
+}
+
+func (r *routeRegexp) matchQueryString(req *http.Request) bool {
+	return r.regexp.MatchString(r.getUrlQuery(req))
+}
+
+// braceIndices returns the first level curly brace indices from a string.
+// It returns an error in case of unbalanced braces.
+func braceIndices(s string) ([]int, error) {
+	var level, idx int
+	idxs := make([]int, 0)
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '{':
+			if level++; level == 1 {
+				idx = i
+			}
+		case '}':
+			if level--; level == 0 {
+				idxs = append(idxs, idx, i+1)
+			} else if level < 0 {
+				return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+			}
+		}
+	}
+	if level != 0 {
+		return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+	}
+	return idxs, nil
+}
+
+// varGroupName builds a capturing group name for the indexed variable.
+func varGroupName(idx int) string {
+	return "v" + strconv.Itoa(idx)
+}
+
+// ----------------------------------------------------------------------------
+// routeRegexpGroup
+// ----------------------------------------------------------------------------
+
+// routeRegexpGroup groups the route matchers that carry variables.
+type routeRegexpGroup struct {
+	host    *routeRegexp
+	path    *routeRegexp
+	queries []*routeRegexp
+}
+
+// setMatch extracts the variables from the URL once a route matches.
+func (v *routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route) {
+	// Store host variables.
+	if v.host != nil {
+		hostVars := v.host.regexp.FindStringSubmatch(getHost(req))
+		if hostVars != nil {
+			subexpNames := v.host.regexp.SubexpNames()
+			varName := 0
+			for i, name := range subexpNames[1:] {
+				if name != "" && name == varGroupName(varName) {
+					m.Vars[v.host.varsN[varName]] = hostVars[i+1]
+					varName++
+				}
+			}
+		}
+	}
+	// Store path variables.
+	if v.path != nil {
+		pathVars := v.path.regexp.FindStringSubmatch(req.URL.Path)
+		if pathVars != nil {
+			subexpNames := v.path.regexp.SubexpNames()
+			varName := 0
+			for i, name := range subexpNames[1:] {
+				if name != "" && name == varGroupName(varName) {
+					m.Vars[v.path.varsN[varName]] = pathVars[i+1]
+					varName++
+				}
+			}
+			// Check if we should redirect.
+			if v.path.strictSlash {
+				p1 := strings.HasSuffix(req.URL.Path, "/")
+				p2 := strings.HasSuffix(v.path.template, "/")
+				if p1 != p2 {
+					u, _ := url.Parse(req.URL.String())
+					if p1 {
+						u.Path = u.Path[:len(u.Path)-1]
+					} else {
+						u.Path += "/"
+					}
+					m.Handler = http.RedirectHandler(u.String(), 301)
+				}
+			}
+		}
+	}
+	// Store query string variables.
+	for _, q := range v.queries {
+		queryVars := q.regexp.FindStringSubmatch(q.getUrlQuery(req))
+		if queryVars != nil {
+			subexpNames := q.regexp.SubexpNames()
+			varName := 0
+			for i, name := range subexpNames[1:] {
+				if name != "" && name == varGroupName(varName) {
+					m.Vars[q.varsN[varName]] = queryVars[i+1]
+					varName++
+				}
+			}
+		}
+	}
+}
+
+// getHost tries its best to return the request host.
+func getHost(r *http.Request) string {
+	if r.URL.IsAbs() {
+		return r.URL.Host
+	}
+	host := r.Host
+	// Slice off any port information.
+	if i := strings.Index(host, ":"); i != -1 {
+		host = host[:i]
+	}
+	return host
+
+}

vendor/github.com/gorilla/mux/route.go

@@ -0,0 +1,595 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// Route stores information to match a request and build URLs.
+type Route struct {
+	// Parent where the route was registered (a Router).
+	parent parentRoute
+	// Request handler for the route.
+	handler http.Handler
+	// List of matchers.
+	matchers []matcher
+	// Manager for the variables from host and path.
+	regexp *routeRegexpGroup
+	// If true, when the path pattern is "/path/", accessing "/path" will
+	// redirect to the former and vice versa.
+	strictSlash bool
+	// If true, this route never matches: it is only used to build URLs.
+	buildOnly bool
+	// The name used to build URLs.
+	name string
+	// Error resulted from building a route.
+	err error
+
+	buildVarsFunc BuildVarsFunc
+}
+
+// Match matches the route against the request.
+func (r *Route) Match(req *http.Request, match *RouteMatch) bool {
+	if r.buildOnly || r.err != nil {
+		return false
+	}
+	// Match everything.
+	for _, m := range r.matchers {
+		if matched := m.Match(req, match); !matched {
+			return false
+		}
+	}
+	// Yay, we have a match. Let's collect some info about it.
+	if match.Route == nil {
+		match.Route = r
+	}
+	if match.Handler == nil {
+		match.Handler = r.handler
+	}
+	if match.Vars == nil {
+		match.Vars = make(map[string]string)
+	}
+	// Set variables.
+	if r.regexp != nil {
+		r.regexp.setMatch(req, match, r)
+	}
+	return true
+}
+
+// ----------------------------------------------------------------------------
+// Route attributes
+// ----------------------------------------------------------------------------
+
+// GetError returns an error resulted from building the route, if any.
+func (r *Route) GetError() error {
+	return r.err
+}
+
+// BuildOnly sets the route to never match: it is only used to build URLs.
+func (r *Route) BuildOnly() *Route {
+	r.buildOnly = true
+	return r
+}
+
+// Handler --------------------------------------------------------------------
+
+// Handler sets a handler for the route.
+func (r *Route) Handler(handler http.Handler) *Route {
+	if r.err == nil {
+		r.handler = handler
+	}
+	return r
+}
+
+// HandlerFunc sets a handler function for the route.
+func (r *Route) HandlerFunc(f func(http.ResponseWriter, *http.Request)) *Route {
+	return r.Handler(http.HandlerFunc(f))
+}
+
+// GetHandler returns the handler for the route, if any.
+func (r *Route) GetHandler() http.Handler {
+	return r.handler
+}
+
+// Name -----------------------------------------------------------------------
+
+// Name sets the name for the route, used to build URLs.
+// If the name was registered already it will be overwritten.
+func (r *Route) Name(name string) *Route {
+	if r.name != "" {
+		r.err = fmt.Errorf("mux: route already has name %q, can't set %q",
+			r.name, name)
+	}
+	if r.err == nil {
+		r.name = name
+		r.getNamedRoutes()[name] = r
+	}
+	return r
+}
+
+// GetName returns the name for the route, if any.
+func (r *Route) GetName() string {
+	return r.name
+}
+
+// ----------------------------------------------------------------------------
+// Matchers
+// ----------------------------------------------------------------------------
+
+// matcher types try to match a request.
+type matcher interface {
+	Match(*http.Request, *RouteMatch) bool
+}
+
+// addMatcher adds a matcher to the route.
+func (r *Route) addMatcher(m matcher) *Route {
+	if r.err == nil {
+		r.matchers = append(r.matchers, m)
+	}
+	return r
+}
+
+// addRegexpMatcher adds a host or path matcher and builder to a route.
+func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix, matchQuery bool) error {
+	if r.err != nil {
+		return r.err
+	}
+	r.regexp = r.getRegexpGroup()
+	if !matchHost && !matchQuery {
+		if len(tpl) == 0 || tpl[0] != '/' {
+			return fmt.Errorf("mux: path must start with a slash, got %q", tpl)
+		}
+		if r.regexp.path != nil {
+			tpl = strings.TrimRight(r.regexp.path.template, "/") + tpl
+		}
+	}
+	rr, err := newRouteRegexp(tpl, matchHost, matchPrefix, matchQuery, r.strictSlash)
+	if err != nil {
+		return err
+	}
+	for _, q := range r.regexp.queries {
+		if err = uniqueVars(rr.varsN, q.varsN); err != nil {
+			return err
+		}
+	}
+	if matchHost {
+		if r.regexp.path != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.path.varsN); err != nil {
+				return err
+			}
+		}
+		r.regexp.host = rr
+	} else {
+		if r.regexp.host != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.host.varsN); err != nil {
+				return err
+			}
+		}
+		if matchQuery {
+			r.regexp.queries = append(r.regexp.queries, rr)
+		} else {
+			r.regexp.path = rr
+		}
+	}
+	r.addMatcher(rr)
+	return nil
+}
+
+// Headers --------------------------------------------------------------------
+
+// headerMatcher matches the request against header values.
+type headerMatcher map[string]string
+
+func (m headerMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithString(m, r.Header, true)
+}
+
+// Headers adds a matcher for request header values.
+// It accepts a sequence of key/value pairs to be matched. For example:
+//
+//     r := mux.NewRouter()
+//     r.Headers("Content-Type", "application/json",
+//               "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both request header values match.
+// If the value is an empty string, it will match any value if the key is set.
+func (r *Route) Headers(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]string
+		headers, r.err = mapFromPairsToString(pairs...)
+		return r.addMatcher(headerMatcher(headers))
+	}
+	return r
+}
+
+// headerRegexMatcher matches the request against the route given a regex for the header
+type headerRegexMatcher map[string]*regexp.Regexp
+
+func (m headerRegexMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithRegex(m, r.Header, true)
+}
+
+// Regular expressions can be used with headers as well.
+// It accepts a sequence of key/value pairs, where the value has regex support. For example
+//     r := mux.NewRouter()
+//     r.HeadersRegexp("Content-Type", "application/(text|json)",
+//               "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both the request header matches both regular expressions.
+// It the value is an empty string, it will match any value if the key is set.
+func (r *Route) HeadersRegexp(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]*regexp.Regexp
+		headers, r.err = mapFromPairsToRegex(pairs...)
+		return r.addMatcher(headerRegexMatcher(headers))
+	}
+	return r
+}
+
+// Host -----------------------------------------------------------------------
+
+// Host adds a matcher for the URL host.
+// It accepts a template with zero or more URL variables enclosed by {}.
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next dot.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Host("www.example.com")
+//     r.Host("{subdomain}.domain.com")
+//     r.Host("{subdomain:[a-z]+}.domain.com")
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Host(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, true, false, false)
+	return r
+}
+
+// MatcherFunc ----------------------------------------------------------------
+
+// MatcherFunc is the function signature used by custom matchers.
+type MatcherFunc func(*http.Request, *RouteMatch) bool
+
+func (m MatcherFunc) Match(r *http.Request, match *RouteMatch) bool {
+	return m(r, match)
+}
+
+// MatcherFunc adds a custom function to be used as request matcher.
+func (r *Route) MatcherFunc(f MatcherFunc) *Route {
+	return r.addMatcher(f)
+}
+
+// Methods --------------------------------------------------------------------
+
+// methodMatcher matches the request against HTTP methods.
+type methodMatcher []string
+
+func (m methodMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.Method)
+}
+
+// Methods adds a matcher for HTTP methods.
+// It accepts a sequence of one or more methods to be matched, e.g.:
+// "GET", "POST", "PUT".
+func (r *Route) Methods(methods ...string) *Route {
+	for k, v := range methods {
+		methods[k] = strings.ToUpper(v)
+	}
+	return r.addMatcher(methodMatcher(methods))
+}
+
+// Path -----------------------------------------------------------------------
+
+// Path adds a matcher for the URL path.
+// It accepts a template with zero or more URL variables enclosed by {}. The
+// template must start with a "/".
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Path("/products/").Handler(ProductsHandler)
+//     r.Path("/products/{key}").Handler(ProductsHandler)
+//     r.Path("/articles/{category}/{id:[0-9]+}").
+//       Handler(ArticleHandler)
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Path(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, false, false, false)
+	return r
+}
+
+// PathPrefix -----------------------------------------------------------------
+
+// PathPrefix adds a matcher for the URL path prefix. This matches if the given
+// template is a prefix of the full URL path. See Route.Path() for details on
+// the tpl argument.
+//
+// Note that it does not treat slashes specially ("/foobar/" will be matched by
+// the prefix "/foo") so you may want to use a trailing slash here.
+//
+// Also note that the setting of Router.StrictSlash() has no effect on routes
+// with a PathPrefix matcher.
+func (r *Route) PathPrefix(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, false, true, false)
+	return r
+}
+
+// Query ----------------------------------------------------------------------
+
+// Queries adds a matcher for URL query values.
+// It accepts a sequence of key/value pairs. Values may define variables.
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Queries("foo", "bar", "id", "{id:[0-9]+}")
+//
+// The above route will only match if the URL contains the defined queries
+// values, e.g.: ?foo=bar&id=42.
+//
+// It the value is an empty string, it will match any value if the key is set.
+//
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+func (r *Route) Queries(pairs ...string) *Route {
+	length := len(pairs)
+	if length%2 != 0 {
+		r.err = fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+		return nil
+	}
+	for i := 0; i < length; i += 2 {
+		if r.err = r.addRegexpMatcher(pairs[i]+"="+pairs[i+1], false, false, true); r.err != nil {
+			return r
+		}
+	}
+
+	return r
+}
+
+// Schemes --------------------------------------------------------------------
+
+// schemeMatcher matches the request against URL schemes.
+type schemeMatcher []string
+
+func (m schemeMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.URL.Scheme)
+}
+
+// Schemes adds a matcher for URL schemes.
+// It accepts a sequence of schemes to be matched, e.g.: "http", "https".
+func (r *Route) Schemes(schemes ...string) *Route {
+	for k, v := range schemes {
+		schemes[k] = strings.ToLower(v)
+	}
+	return r.addMatcher(schemeMatcher(schemes))
+}
+
+// BuildVarsFunc --------------------------------------------------------------
+
+// BuildVarsFunc is the function signature used by custom build variable
+// functions (which can modify route variables before a route's URL is built).
+type BuildVarsFunc func(map[string]string) map[string]string
+
+// BuildVarsFunc adds a custom function to be used to modify build variables
+// before a route's URL is built.
+func (r *Route) BuildVarsFunc(f BuildVarsFunc) *Route {
+	r.buildVarsFunc = f
+	return r
+}
+
+// Subrouter ------------------------------------------------------------------
+
+// Subrouter creates a subrouter for the route.
+//
+// It will test the inner routes only if the parent route matched. For example:
+//
+//     r := mux.NewRouter()
+//     s := r.Host("www.example.com").Subrouter()
+//     s.HandleFunc("/products/", ProductsHandler)
+//     s.HandleFunc("/products/{key}", ProductHandler)
+//     s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+//
+// Here, the routes registered in the subrouter won't be tested if the host
+// doesn't match.
+func (r *Route) Subrouter() *Router {
+	router := &Router{parent: r, strictSlash: r.strictSlash}
+	r.addMatcher(router)
+	return router
+}
+
+// ----------------------------------------------------------------------------
+// URL building
+// ----------------------------------------------------------------------------
+
+// URL builds a URL for the route.
+//
+// It accepts a sequence of key/value pairs for the route variables. For
+// example, given this route:
+//
+//     r := mux.NewRouter()
+//     r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//       Name("article")
+//
+// ...a URL for it can be built using:
+//
+//     url, err := r.Get("article").URL("category", "technology", "id", "42")
+//
+// ...which will return an url.URL with the following path:
+//
+//     "/articles/technology/42"
+//
+// This also works for host variables:
+//
+//     r := mux.NewRouter()
+//     r.Host("{subdomain}.domain.com").
+//       HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//       Name("article")
+//
+//     // url.String() will be "http://news.domain.com/articles/technology/42"
+//     url, err := r.Get("article").URL("subdomain", "news",
+//                                      "category", "technology",
+//                                      "id", "42")
+//
+// All variables defined in the route are required, and their values must
+// conform to the corresponding patterns.
+func (r *Route) URL(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil {
+		return nil, errors.New("mux: route doesn't have a host or path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	var scheme, host, path string
+	if r.regexp.host != nil {
+		// Set a default scheme.
+		scheme = "http"
+		if host, err = r.regexp.host.url(values); err != nil {
+			return nil, err
+		}
+	}
+	if r.regexp.path != nil {
+		if path, err = r.regexp.path.url(values); err != nil {
+			return nil, err
+		}
+	}
+	return &url.URL{
+		Scheme: scheme,
+		Host:   host,
+		Path:   path,
+	}, nil
+}
+
+// URLHost builds the host part of the URL for a route. See Route.URL().
+//
+// The route must have a host defined.
+func (r *Route) URLHost(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.host == nil {
+		return nil, errors.New("mux: route doesn't have a host")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	host, err := r.regexp.host.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Scheme: "http",
+		Host:   host,
+	}, nil
+}
+
+// URLPath builds the path part of the URL for a route. See Route.URL().
+//
+// The route must have a path defined.
+func (r *Route) URLPath(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.path == nil {
+		return nil, errors.New("mux: route doesn't have a path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	path, err := r.regexp.path.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Path: path,
+	}, nil
+}
+
+// prepareVars converts the route variable pairs into a map. If the route has a
+// BuildVarsFunc, it is invoked.
+func (r *Route) prepareVars(pairs ...string) (map[string]string, error) {
+	m, err := mapFromPairsToString(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	return r.buildVars(m), nil
+}
+
+func (r *Route) buildVars(m map[string]string) map[string]string {
+	if r.parent != nil {
+		m = r.parent.buildVars(m)
+	}
+	if r.buildVarsFunc != nil {
+		m = r.buildVarsFunc(m)
+	}
+	return m
+}
+
+// ----------------------------------------------------------------------------
+// parentRoute
+// ----------------------------------------------------------------------------
+
+// parentRoute allows routes to know about parent host and path definitions.
+type parentRoute interface {
+	getNamedRoutes() map[string]*Route
+	getRegexpGroup() *routeRegexpGroup
+	buildVars(map[string]string) map[string]string
+}
+
+// getNamedRoutes returns the map where named routes are registered.
+func (r *Route) getNamedRoutes() map[string]*Route {
+	if r.parent == nil {
+		// During tests router is not always set.
+		r.parent = NewRouter()
+	}
+	return r.parent.getNamedRoutes()
+}
+
+// getRegexpGroup returns regexp definitions from this route.
+func (r *Route) getRegexpGroup() *routeRegexpGroup {
+	if r.regexp == nil {
+		if r.parent == nil {
+			// During tests router is not always set.
+			r.parent = NewRouter()
+		}
+		regexp := r.parent.getRegexpGroup()
+		if regexp == nil {
+			r.regexp = new(routeRegexpGroup)
+		} else {
+			// Copy.
+			r.regexp = &routeRegexpGroup{
+				host:    regexp.host,
+				path:    regexp.path,
+				queries: regexp.queries,
+			}
+		}
+	}
+	return r.regexp
+}

vendor/github.com/matttproud/golang_protobuf_extensions/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright 2013 Matt T. Proud
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/decode.go

@@ -0,0 +1,75 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+var errInvalidVarint = errors.New("invalid varint32 encountered")
+
+// ReadDelimited decodes a message from the provided length-delimited stream,
+// where the length is encoded as 32-bit varint prefix to the message body.
+// It returns the total number of bytes read and any applicable error.  This is
+// roughly equivalent to the companion Java API's
+// MessageLite#parseDelimitedFrom.  As per the reader contract, this function
+// calls r.Read repeatedly as required until exactly one message including its
+// prefix is read and decoded (or an error has occurred).  The function never
+// reads more bytes from the stream than required.  The function never returns
+// an error if a message has been read and decoded correctly, even if the end
+// of the stream has been reached in doing so.  In that case, any subsequent
+// calls return (0, io.EOF).
+func ReadDelimited(r io.Reader, m proto.Message) (n int, err error) {
+	// Per AbstractParser#parsePartialDelimitedFrom with
+	// CodedInputStream#readRawVarint32.
+	headerBuf := make([]byte, binary.MaxVarintLen32)
+	var bytesRead, varIntBytes int
+	var messageLength uint64
+	for varIntBytes == 0 { // i.e. no varint has been decoded yet.
+		if bytesRead >= len(headerBuf) {
+			return bytesRead, errInvalidVarint
+		}
+		// We have to read byte by byte here to avoid reading more bytes
+		// than required. Each read byte is appended to what we have
+		// read before.
+		newBytesRead, err := r.Read(headerBuf[bytesRead : bytesRead+1])
+		if newBytesRead == 0 {
+			if err != nil {
+				return bytesRead, err
+			}
+			// A Reader should not return (0, nil), but if it does,
+			// it should be treated as no-op (according to the
+			// Reader contract). So let's go on...
+			continue
+		}
+		bytesRead += newBytesRead
+		// Now present everything read so far to the varint decoder and
+		// see if a varint can be decoded already.
+		messageLength, varIntBytes = proto.DecodeVarint(headerBuf[:bytesRead])
+	}
+
+	messageBuf := make([]byte, messageLength)
+	newBytesRead, err := io.ReadFull(r, messageBuf)
+	bytesRead += newBytesRead
+	if err != nil {
+		return bytesRead, err
+	}
+
+	return bytesRead, proto.Unmarshal(messageBuf, m)
+}

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/doc.go

@@ -0,0 +1,16 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package pbutil provides record length-delimited Protocol Buffer streaming.
+package pbutil

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/encode.go

@@ -0,0 +1,46 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// WriteDelimited encodes and dumps a message to the provided writer prefixed
+// with a 32-bit varint indicating the length of the encoded message, producing
+// a length-delimited record stream, which can be used to chain together
+// encoded messages of the same type together in a file.  It returns the total
+// number of bytes written and any applicable error.  This is roughly
+// equivalent to the companion Java API's MessageLite#writeDelimitedTo.
+func WriteDelimited(w io.Writer, m proto.Message) (n int, err error) {
+	buffer, err := proto.Marshal(m)
+	if err != nil {
+		return 0, err
+	}
+
+	buf := make([]byte, binary.MaxVarintLen32)
+	encodedLength := binary.PutUvarint(buf, uint64(len(buffer)))
+
+	sync, err := w.Write(buf[:encodedLength])
+	if err != nil {
+		return sync, err
+	}
+
+	n, err = w.Write(buffer)
+	return n + sync, err
+}

vendor/github.com/prometheus/client_golang/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/client_golang/NOTICE

@@ -0,0 +1,28 @@
+Prometheus instrumentation library for Go applications
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
+
+
+The following components are included in this product:
+
+goautoneg
+http://bitbucket.org/ww/goautoneg
+Copyright 2011, Open Knowledge Foundation Ltd.
+See README.txt for license details.
+
+perks - a fork of https://github.com/bmizerany/perks
+https://github.com/beorn7/perks
+Copyright 2013-2015 Blake Mizerany, Björn Rabenstein
+See https://github.com/beorn7/perks/blob/master/README.md for license details.
+
+Go support for Protocol Buffers - Google's data interchange format
+http://github.com/golang/protobuf/
+Copyright 2010 The Go Authors
+See source code for license details.
+
+Support for streaming Protocol Buffer messages for the Go language (golang).
+https://github.com/matttproud/golang_protobuf_extensions
+Copyright 2013 Matt T. Proud
+Licensed under the Apache License, Version 2.0

vendor/github.com/prometheus/client_golang/prometheus/.gitignore

@@ -0,0 +1 @@
+command-line-arguments.test

vendor/github.com/prometheus/client_golang/prometheus/README.md

@@ -0,0 +1,53 @@
+# Overview
+This is the [Prometheus](http://www.prometheus.io) telemetric
+instrumentation client [Go](http://golang.org) client library.  It
+enable authors to define process-space metrics for their servers and
+expose them through a web service interface for extraction,
+aggregation, and a whole slew of other post processing techniques.
+
+# Installing
+    $ go get github.com/prometheus/client_golang/prometheus
+
+# Example
+```go
+package main
+
+import (
+	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	indexed = prometheus.NewCounter(prometheus.CounterOpts{
+		Namespace: "my_company",
+		Subsystem: "indexer",
+		Name:      "documents_indexed",
+		Help:      "The number of documents indexed.",
+	})
+	size = prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: "my_company",
+		Subsystem: "storage",
+		Name:      "documents_total_size_bytes",
+		Help:      "The total size of all documents in the storage.",
+	})
+)
+
+func main() {
+	http.Handle("/metrics", prometheus.Handler())
+
+	indexed.Inc()
+	size.Set(5)
+
+	http.ListenAndServe(":8080", nil)
+}
+
+func init() {
+	prometheus.MustRegister(indexed)
+	prometheus.MustRegister(size)
+}
+```
+
+# Documentation
+
+[![GoDoc](https://godoc.org/github.com/prometheus/client_golang?status.png)](https://godoc.org/github.com/prometheus/client_golang)

vendor/github.com/prometheus/client_golang/prometheus/collector.go

@@ -0,0 +1,75 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Collector is the interface implemented by anything that can be used by
+// Prometheus to collect metrics. A Collector has to be registered for
+// collection. See Register, MustRegister, RegisterOrGet, and MustRegisterOrGet.
+//
+// The stock metrics provided by this package (like Gauge, Counter, Summary) are
+// also Collectors (which only ever collect one metric, namely itself). An
+// implementer of Collector may, however, collect multiple metrics in a
+// coordinated fashion and/or create metrics on the fly. Examples for collectors
+// already implemented in this library are the metric vectors (i.e. collection
+// of multiple instances of the same Metric but with different label values)
+// like GaugeVec or SummaryVec, and the ExpvarCollector.
+type Collector interface {
+	// Describe sends the super-set of all possible descriptors of metrics
+	// collected by this Collector to the provided channel and returns once
+	// the last descriptor has been sent. The sent descriptors fulfill the
+	// consistency and uniqueness requirements described in the Desc
+	// documentation. (It is valid if one and the same Collector sends
+	// duplicate descriptors. Those duplicates are simply ignored. However,
+	// two different Collectors must not send duplicate descriptors.) This
+	// method idempotently sends the same descriptors throughout the
+	// lifetime of the Collector. If a Collector encounters an error while
+	// executing this method, it must send an invalid descriptor (created
+	// with NewInvalidDesc) to signal the error to the registry.
+	Describe(chan<- *Desc)
+	// Collect is called by Prometheus when collecting metrics. The
+	// implementation sends each collected metric via the provided channel
+	// and returns once the last metric has been sent. The descriptor of
+	// each sent metric is one of those returned by Describe. Returned
+	// metrics that share the same descriptor must differ in their variable
+	// label values. This method may be called concurrently and must
+	// therefore be implemented in a concurrency safe way. Blocking occurs
+	// at the expense of total performance of rendering all registered
+	// metrics. Ideally, Collector implementations support concurrent
+	// readers.
+	Collect(chan<- Metric)
+}
+
+// SelfCollector implements Collector for a single Metric so that that the
+// Metric collects itself. Add it as an anonymous field to a struct that
+// implements Metric, and call Init with the Metric itself as an argument.
+type SelfCollector struct {
+	self Metric
+}
+
+// Init provides the SelfCollector with a reference to the metric it is supposed
+// to collect. It is usually called within the factory function to create a
+// metric. See example.
+func (c *SelfCollector) Init(self Metric) {
+	c.self = self
+}
+
+// Describe implements Collector.
+func (c *SelfCollector) Describe(ch chan<- *Desc) {
+	ch <- c.self.Desc()
+}
+
+// Collect implements Collector.
+func (c *SelfCollector) Collect(ch chan<- Metric) {
+	ch <- c.self
+}

vendor/github.com/prometheus/client_golang/prometheus/counter.go

@@ -0,0 +1,175 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"hash/fnv"
+)
+
+// Counter is a Metric that represents a single numerical value that only ever
+// goes up. That implies that it cannot be used to count items whose number can
+// also go down, e.g. the number of currently running goroutines. Those
+// "counters" are represented by Gauges.
+//
+// A Counter is typically used to count requests served, tasks completed, errors
+// occurred, etc.
+//
+// To create Counter instances, use NewCounter.
+type Counter interface {
+	Metric
+	Collector
+
+	// Set is used to set the Counter to an arbitrary value. It is only used
+	// if you have to transfer a value from an external counter into this
+	// Prometheus metric. Do not use it for regular handling of a
+	// Prometheus counter (as it can be used to break the contract of
+	// monotonically increasing values).
+	Set(float64)
+	// Inc increments the counter by 1.
+	Inc()
+	// Add adds the given value to the counter. It panics if the value is <
+	// 0.
+	Add(float64)
+}
+
+// CounterOpts is an alias for Opts. See there for doc comments.
+type CounterOpts Opts
+
+// NewCounter creates a new Counter based on the provided CounterOpts.
+func NewCounter(opts CounterOpts) Counter {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	)
+	result := &counter{value: value{desc: desc, valType: CounterValue, labelPairs: desc.constLabelPairs}}
+	result.Init(result) // Init self-collection.
+	return result
+}
+
+type counter struct {
+	value
+}
+
+func (c *counter) Add(v float64) {
+	if v < 0 {
+		panic(errors.New("counter cannot decrease in value"))
+	}
+	c.value.Add(v)
+}
+
+// CounterVec is a Collector that bundles a set of Counters that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. number of HTTP requests, partitioned by response code and
+// method). Create instances with NewCounterVec.
+//
+// CounterVec embeds MetricVec. See there for a full list of methods with
+// detailed documentation.
+type CounterVec struct {
+	MetricVec
+}
+
+// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &CounterVec{
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				result := &counter{value: value{
+					desc:       desc,
+					valType:    CounterValue,
+					labelPairs: makeLabelPairs(desc, lvs),
+				}}
+				result.Init(result) // Init self-collection.
+				return result
+			},
+		},
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Counter and not a
+// Metric so that no type conversion is required.
+func (m *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Counter and not a Metric so that no
+// type conversion is required.
+func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *CounterVec) WithLabelValues(lvs ...string) Counter {
+	return m.MetricVec.WithLabelValues(lvs...).(Counter)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+func (m *CounterVec) With(labels Labels) Counter {
+	return m.MetricVec.With(labels).(Counter)
+}
+
+// CounterFunc is a Counter whose value is determined at collect time by calling a
+// provided function.
+//
+// To create CounterFunc instances, use NewCounterFunc.
+type CounterFunc interface {
+	Metric
+	Collector
+}
+
+// NewCounterFunc creates a new CounterFunc based on the provided
+// CounterOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a CounterFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe. The function should also honor
+// the contract for a Counter (values only go up, not down), but compliance will
+// not be checked.
+func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), CounterValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/desc.go

@@ -0,0 +1,201 @@
+package prometheus
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"hash/fnv"
+	"regexp"
+	"sort"
+	"strings"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+var (
+	metricNameRE = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_:]*$`)
+	labelNameRE  = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+)
+
+// reservedLabelPrefix is a prefix which is not legal in user-supplied
+// label names.
+const reservedLabelPrefix = "__"
+
+// Labels represents a collection of label name -> value mappings. This type is
+// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
+// metric vector Collectors, e.g.:
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+//
+// The other use-case is the specification of constant label pairs in Opts or to
+// create a Desc.
+type Labels map[string]string
+
+// Desc is the descriptor used by every Prometheus Metric. It is essentially
+// the immutable meta-data of a Metric. The normal Metric implementations
+// included in this package manage their Desc under the hood. Users only have to
+// deal with Desc if they use advanced features like the ExpvarCollector or
+// custom Collectors and Metrics.
+//
+// Descriptors registered with the same registry have to fulfill certain
+// consistency and uniqueness criteria if they share the same fully-qualified
+// name: They must have the same help string and the same label names (aka label
+// dimensions) in each, constLabels and variableLabels, but they must differ in
+// the values of the constLabels.
+//
+// Descriptors that share the same fully-qualified names and the same label
+// values of their constLabels are considered equal.
+//
+// Use NewDesc to create new Desc instances.
+type Desc struct {
+	// fqName has been built from Namespace, Subsystem, and Name.
+	fqName string
+	// help provides some helpful information about this metric.
+	help string
+	// constLabelPairs contains precalculated DTO label pairs based on
+	// the constant labels.
+	constLabelPairs []*dto.LabelPair
+	// VariableLabels contains names of labels for which the metric
+	// maintains variable values.
+	variableLabels []string
+	// id is a hash of the values of the ConstLabels and fqName. This
+	// must be unique among all registered descriptors and can therefore be
+	// used as an identifier of the descriptor.
+	id uint64
+	// dimHash is a hash of the label names (preset and variable) and the
+	// Help string. Each Desc with the same fqName must have the same
+	// dimHash.
+	dimHash uint64
+	// err is an error that occured during construction. It is reported on
+	// registration time.
+	err error
+}
+
+// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
+// and will be reported on registration time. variableLabels and constLabels can
+// be nil if no such labels should be set. fqName and help must not be empty.
+//
+// variableLabels only contain the label names. Their label values are variable
+// and therefore not part of the Desc. (They are managed within the Metric.)
+//
+// For constLabels, the label values are constant. Therefore, they are fully
+// specified in the Desc. See the Opts documentation for the implications of
+// constant labels.
+func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc {
+	d := &Desc{
+		fqName:         fqName,
+		help:           help,
+		variableLabels: variableLabels,
+	}
+	if help == "" {
+		d.err = errors.New("empty help string")
+		return d
+	}
+	if !metricNameRE.MatchString(fqName) {
+		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
+		return d
+	}
+	// labelValues contains the label values of const labels (in order of
+	// their sorted label names) plus the fqName (at position 0).
+	labelValues := make([]string, 1, len(constLabels)+1)
+	labelValues[0] = fqName
+	labelNames := make([]string, 0, len(constLabels)+len(variableLabels))
+	labelNameSet := map[string]struct{}{}
+	// First add only the const label names and sort them...
+	for labelName := range constLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name", labelName)
+			return d
+		}
+		labelNames = append(labelNames, labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	sort.Strings(labelNames)
+	// ... so that we can now add const label values in the order of their names.
+	for _, labelName := range labelNames {
+		labelValues = append(labelValues, constLabels[labelName])
+	}
+	// Now add the variable label names, but prefix them with something that
+	// cannot be in a regular label name. That prevents matching the label
+	// dimension with a different mix between preset and variable labels.
+	for _, labelName := range variableLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name", labelName)
+			return d
+		}
+		labelNames = append(labelNames, "$"+labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	if len(labelNames) != len(labelNameSet) {
+		d.err = errors.New("duplicate label names")
+		return d
+	}
+	h := fnv.New64a()
+	var b bytes.Buffer // To copy string contents into, avoiding []byte allocations.
+	for _, val := range labelValues {
+		b.Reset()
+		b.WriteString(val)
+		b.WriteByte(separatorByte)
+		h.Write(b.Bytes())
+	}
+	d.id = h.Sum64()
+	// Sort labelNames so that order doesn't matter for the hash.
+	sort.Strings(labelNames)
+	// Now hash together (in this order) the help string and the sorted
+	// label names.
+	h.Reset()
+	b.Reset()
+	b.WriteString(help)
+	b.WriteByte(separatorByte)
+	h.Write(b.Bytes())
+	for _, labelName := range labelNames {
+		b.Reset()
+		b.WriteString(labelName)
+		b.WriteByte(separatorByte)
+		h.Write(b.Bytes())
+	}
+	d.dimHash = h.Sum64()
+
+	d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels))
+	for n, v := range constLabels {
+		d.constLabelPairs = append(d.constLabelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(v),
+		})
+	}
+	sort.Sort(LabelPairSorter(d.constLabelPairs))
+	return d
+}
+
+// NewInvalidDesc returns an invalid descriptor, i.e. a descriptor with the
+// provided error set. If a collector returning such a descriptor is registered,
+// registration will fail with the provided error. NewInvalidDesc can be used by
+// a Collector to signal inability to describe itself.
+func NewInvalidDesc(err error) *Desc {
+	return &Desc{
+		err: err,
+	}
+}
+
+func (d *Desc) String() string {
+	lpStrings := make([]string, 0, len(d.constLabelPairs))
+	for _, lp := range d.constLabelPairs {
+		lpStrings = append(
+			lpStrings,
+			fmt.Sprintf("%s=%q", lp.GetName(), lp.GetValue()),
+		)
+	}
+	return fmt.Sprintf(
+		"Desc{fqName: %q, help: %q, constLabels: {%s}, variableLabels: %v}",
+		d.fqName,
+		d.help,
+		strings.Join(lpStrings, ","),
+		d.variableLabels,
+	)
+}
+
+func checkLabelName(l string) bool {
+	return labelNameRE.MatchString(l) &&
+		!strings.HasPrefix(l, reservedLabelPrefix)
+}

vendor/github.com/prometheus/client_golang/prometheus/doc.go

@@ -0,0 +1,109 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package prometheus provides embeddable metric primitives for servers and
+// standardized exposition of telemetry through a web services interface.
+//
+// All exported functions and methods are safe to be used concurrently unless
+// specified otherwise.
+//
+// To expose metrics registered with the Prometheus registry, an HTTP server
+// needs to know about the Prometheus handler. The usual endpoint is "/metrics".
+//
+//     http.Handle("/metrics", prometheus.Handler())
+//
+// As a starting point a very basic usage example:
+//
+//    package main
+//
+//    import (
+//    	"net/http"
+//
+//    	"github.com/prometheus/client_golang/prometheus"
+//    )
+//
+//    var (
+//    	cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{
+//    		Name: "cpu_temperature_celsius",
+//    		Help: "Current temperature of the CPU.",
+//    	})
+//    	hdFailures = prometheus.NewCounter(prometheus.CounterOpts{
+//    		Name: "hd_errors_total",
+//    		Help: "Number of hard-disk errors.",
+//    	})
+//    )
+//
+//    func init() {
+//    	prometheus.MustRegister(cpuTemp)
+//    	prometheus.MustRegister(hdFailures)
+//    }
+//
+//    func main() {
+//    	cpuTemp.Set(65.3)
+//    	hdFailures.Inc()
+//
+//    	http.Handle("/metrics", prometheus.Handler())
+//    	http.ListenAndServe(":8080", nil)
+//    }
+//
+//
+// This is a complete program that exports two metrics, a Gauge and a Counter.
+// It also exports some stats about the HTTP usage of the /metrics
+// endpoint. (See the Handler function for more detail.)
+//
+// Two more advanced metric types are the Summary and Histogram.
+//
+// In addition to the fundamental metric types Gauge, Counter, Summary, and
+// Histogram, a very important part of the Prometheus data model is the
+// partitioning of samples along dimensions called labels, which results in
+// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec,
+// and HistogramVec.
+//
+// Those are all the parts needed for basic usage. Detailed documentation and
+// examples are provided below.
+//
+// Everything else this package offers is essentially for "power users" only. A
+// few pointers to "power user features":
+//
+// All the various ...Opts structs have a ConstLabels field for labels that
+// never change their value (which is only useful under special circumstances,
+// see documentation of the Opts type).
+//
+// The Untyped metric behaves like a Gauge, but signals the Prometheus server
+// not to assume anything about its type.
+//
+// Functions to fine-tune how the metric registry works: EnableCollectChecks,
+// PanicOnCollectError, Register, Unregister, SetMetricFamilyInjectionHook.
+//
+// For custom metric collection, there are two entry points: Custom Metric
+// implementations and custom Collector implementations. A Metric is the
+// fundamental unit in the Prometheus data model: a sample at a point in time
+// together with its meta-data (like its fully-qualified name and any number of
+// pairs of label name and label value) that knows how to marshal itself into a
+// data transfer object (aka DTO, implemented as a protocol buffer). A Collector
+// gets registered with the Prometheus registry and manages the collection of
+// one or more Metrics. Many parts of this package are building blocks for
+// Metrics and Collectors. Desc is the metric descriptor, actually used by all
+// metrics under the hood, and by Collectors to describe the Metrics to be
+// collected, but only to be dealt with by users if they implement their own
+// Metrics or Collectors. To create a Desc, the BuildFQName function will come
+// in handy. Other useful components for Metric and Collector implementation
+// include: LabelPairSorter to sort the DTO version of label pairs,
+// NewConstMetric and MustNewConstMetric to create "throw away" Metrics at
+// collection time, MetricVec to bundle custom Metrics into a metric vector
+// Collector, SelfCollector to make a custom Metric collect itself.
+//
+// A good example for a custom Collector is the ExpVarCollector included in this
+// package, which exports variables exported via the "expvar" package as
+// Prometheus metrics.
+package prometheus

vendor/github.com/prometheus/client_golang/prometheus/expvar.go

@@ -0,0 +1,119 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"encoding/json"
+	"expvar"
+)
+
+// ExpvarCollector collects metrics from the expvar interface. It provides a
+// quick way to expose numeric values that are already exported via expvar as
+// Prometheus metrics. Note that the data models of expvar and Prometheus are
+// fundamentally different, and that the ExpvarCollector is inherently
+// slow. Thus, the ExpvarCollector is probably great for experiments and
+// prototying, but you should seriously consider a more direct implementation of
+// Prometheus metrics for monitoring production systems.
+//
+// Use NewExpvarCollector to create new instances.
+type ExpvarCollector struct {
+	exports map[string]*Desc
+}
+
+// NewExpvarCollector returns a newly allocated ExpvarCollector that still has
+// to be registered with the Prometheus registry.
+//
+// The exports map has the following meaning:
+//
+// The keys in the map correspond to expvar keys, i.e. for every expvar key you
+// want to export as Prometheus metric, you need an entry in the exports
+// map. The descriptor mapped to each key describes how to export the expvar
+// value. It defines the name and the help string of the Prometheus metric
+// proxying the expvar value. The type will always be Untyped.
+//
+// For descriptors without variable labels, the expvar value must be a number or
+// a bool. The number is then directly exported as the Prometheus sample
+// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values
+// that are not numbers or bools are silently ignored.
+//
+// If the descriptor has one variable label, the expvar value must be an expvar
+// map. The keys in the expvar map become the various values of the one
+// Prometheus label. The values in the expvar map must be numbers or bools again
+// as above.
+//
+// For descriptors with more than one variable label, the expvar must be a
+// nested expvar map, i.e. where the values of the topmost map are maps again
+// etc. until a depth is reached that corresponds to the number of labels. The
+// leaves of that structure must be numbers or bools as above to serve as the
+// sample values.
+//
+// Anything that does not fit into the scheme above is silently ignored.
+func NewExpvarCollector(exports map[string]*Desc) *ExpvarCollector {
+	return &ExpvarCollector{
+		exports: exports,
+	}
+}
+
+// Describe implements Collector.
+func (e *ExpvarCollector) Describe(ch chan<- *Desc) {
+	for _, desc := range e.exports {
+		ch <- desc
+	}
+}
+
+// Collect implements Collector.
+func (e *ExpvarCollector) Collect(ch chan<- Metric) {
+	for name, desc := range e.exports {
+		var m Metric
+		expVar := expvar.Get(name)
+		if expVar == nil {
+			continue
+		}
+		var v interface{}
+		labels := make([]string, len(desc.variableLabels))
+		if err := json.Unmarshal([]byte(expVar.String()), &v); err != nil {
+			ch <- NewInvalidMetric(desc, err)
+			continue
+		}
+		var processValue func(v interface{}, i int)
+		processValue = func(v interface{}, i int) {
+			if i >= len(labels) {
+				copiedLabels := append(make([]string, 0, len(labels)), labels...)
+				switch v := v.(type) {
+				case float64:
+					m = MustNewConstMetric(desc, UntypedValue, v, copiedLabels...)
+				case bool:
+					if v {
+						m = MustNewConstMetric(desc, UntypedValue, 1, copiedLabels...)
+					} else {
+						m = MustNewConstMetric(desc, UntypedValue, 0, copiedLabels...)
+					}
+				default:
+					return
+				}
+				ch <- m
+				return
+			}
+			vm, ok := v.(map[string]interface{})
+			if !ok {
+				return
+			}
+			for lv, val := range vm {
+				labels[i] = lv
+				processValue(val, i+1)
+			}
+		}
+		processValue(v, 0)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/gauge.go

@@ -0,0 +1,147 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import "hash/fnv"
+
+// Gauge is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// A Gauge is typically used for measured values like temperatures or current
+// memory usage, but also "counts" that can go up and down, like the number of
+// running goroutines.
+//
+// To create Gauge instances, use NewGauge.
+type Gauge interface {
+	Metric
+	Collector
+
+	// Set sets the Gauge to an arbitrary value.
+	Set(float64)
+	// Inc increments the Gauge by 1.
+	Inc()
+	// Dec decrements the Gauge by 1.
+	Dec()
+	// Add adds the given value to the Gauge. (The value can be
+	// negative, resulting in a decrease of the Gauge.)
+	Add(float64)
+	// Sub subtracts the given value from the Gauge. (The value can be
+	// negative, resulting in an increase of the Gauge.)
+	Sub(float64)
+}
+
+// GaugeOpts is an alias for Opts. See there for doc comments.
+type GaugeOpts Opts
+
+// NewGauge creates a new Gauge based on the provided GaugeOpts.
+func NewGauge(opts GaugeOpts) Gauge {
+	return newValue(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), GaugeValue, 0)
+}
+
+// GaugeVec is a Collector that bundles a set of Gauges that all share the same
+// Desc, but have different values for their variable labels. This is used if
+// you want to count the same thing partitioned by various dimensions
+// (e.g. number of operations queued, partitioned by user and operation
+// type). Create instances with NewGaugeVec.
+type GaugeVec struct {
+	MetricVec
+}
+
+// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &GaugeVec{
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newValue(desc, GaugeValue, 0, lvs...)
+			},
+		},
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Gauge and not a
+// Metric so that no type conversion is required.
+func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Gauge), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Gauge and not a Metric so that no
+// type conversion is required.
+func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Gauge), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge {
+	return m.MetricVec.WithLabelValues(lvs...).(Gauge)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+func (m *GaugeVec) With(labels Labels) Gauge {
+	return m.MetricVec.With(labels).(Gauge)
+}
+
+// GaugeFunc is a Gauge whose value is determined at collect time by calling a
+// provided function.
+//
+// To create GaugeFunc instances, use NewGaugeFunc.
+type GaugeFunc interface {
+	Metric
+	Collector
+}
+
+// NewGaugeFunc creates a new GaugeFunc based on the provided GaugeOpts. The
+// value reported is determined by calling the given function from within the
+// Write method. Take into account that metric collection may happen
+// concurrently. If that results in concurrent calls to Write, like in the case
+// where a GaugeFunc is directly registered with Prometheus, the provided
+// function must be concurrency-safe.
+func NewGaugeFunc(opts GaugeOpts, function func() float64) GaugeFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), GaugeValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/go_collector.go

@@ -0,0 +1,50 @@
+package prometheus
+
+import (
+	"runtime"
+	"runtime/debug"
+	"time"
+)
+
+type goCollector struct {
+	goroutines Gauge
+	gcDesc     *Desc
+}
+
+// NewGoCollector returns a collector which exports metrics about the current
+// go process.
+func NewGoCollector() *goCollector {
+	return &goCollector{
+		goroutines: NewGauge(GaugeOpts{
+			Name: "go_goroutines",
+			Help: "Number of goroutines that currently exist.",
+		}),
+		gcDesc: NewDesc(
+			"go_gc_duration_seconds",
+			"A summary of the GC invocation durations.",
+			nil, nil),
+	}
+}
+
+// Describe returns all descriptions of the collector.
+func (c *goCollector) Describe(ch chan<- *Desc) {
+	ch <- c.goroutines.Desc()
+	ch <- c.gcDesc
+}
+
+// Collect returns the current state of all metrics of the collector.
+func (c *goCollector) Collect(ch chan<- Metric) {
+	c.goroutines.Set(float64(runtime.NumGoroutine()))
+	ch <- c.goroutines
+
+	var stats debug.GCStats
+	stats.PauseQuantiles = make([]time.Duration, 5)
+	debug.ReadGCStats(&stats)
+
+	quantiles := make(map[float64]float64)
+	for idx, pq := range stats.PauseQuantiles[1:] {
+		quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds()
+	}
+	quantiles[0.0] = stats.PauseQuantiles[0].Seconds()
+	ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), float64(stats.PauseTotal.Seconds()), quantiles)
+}

vendor/github.com/prometheus/client_golang/prometheus/histogram.go

@@ -0,0 +1,450 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"hash/fnv"
+	"math"
+	"sort"
+	"sync/atomic"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// A Histogram counts individual observations from an event or sample stream in
+// configurable buckets. Similar to a summary, it also provides a sum of
+// observations and an observation count.
+//
+// On the Prometheus server, quantiles can be calculated from a Histogram using
+// the histogram_quantile function in the query language.
+//
+// Note that Histograms, in contrast to Summaries, can be aggregated with the
+// Prometheus query language (see the documentation for detailed
+// procedures). However, Histograms require the user to pre-define suitable
+// buckets, and they are in general less accurate. The Observe method of a
+// Histogram has a very low performance overhead in comparison with the Observe
+// method of a Summary.
+//
+// To create Histogram instances, use NewHistogram.
+type Histogram interface {
+	Metric
+	Collector
+
+	// Observe adds a single observation to the histogram.
+	Observe(float64)
+}
+
+// bucketLabel is used for the label that defines the upper bound of a
+// bucket of a histogram ("le" -> "less or equal").
+const bucketLabel = "le"
+
+var (
+	// DefBuckets are the default Histogram buckets. The default buckets are
+	// tailored to broadly measure the response time (in seconds) of a
+	// network service. Most likely, however, you will be required to define
+	// buckets customized to your use case.
+	DefBuckets = []float64{.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10}
+
+	errBucketLabelNotAllowed = fmt.Errorf(
+		"%q is not allowed as label name in histograms", bucketLabel,
+	)
+)
+
+// LinearBuckets creates 'count' buckets, each 'width' wide, where the lowest
+// bucket has an upper bound of 'start'. The final +Inf bucket is not counted
+// and not included in the returned slice. The returned slice is meant to be
+// used for the Buckets field of HistogramOpts.
+//
+// The function panics if 'count' is zero or negative.
+func LinearBuckets(start, width float64, count int) []float64 {
+	if count < 1 {
+		panic("LinearBuckets needs a positive count")
+	}
+	buckets := make([]float64, count)
+	for i := range buckets {
+		buckets[i] = start
+		start += width
+	}
+	return buckets
+}
+
+// ExponentialBuckets creates 'count' buckets, where the lowest bucket has an
+// upper bound of 'start' and each following bucket's upper bound is 'factor'
+// times the previous bucket's upper bound. The final +Inf bucket is not counted
+// and not included in the returned slice. The returned slice is meant to be
+// used for the Buckets field of HistogramOpts.
+//
+// The function panics if 'count' is 0 or negative, if 'start' is 0 or negative,
+// or if 'factor' is less than or equal 1.
+func ExponentialBuckets(start, factor float64, count int) []float64 {
+	if count < 1 {
+		panic("ExponentialBuckets needs a positive count")
+	}
+	if start <= 0 {
+		panic("ExponentialBuckets needs a positive start value")
+	}
+	if factor <= 1 {
+		panic("ExponentialBuckets needs a factor greater than 1")
+	}
+	buckets := make([]float64, count)
+	for i := range buckets {
+		buckets[i] = start
+		start *= factor
+	}
+	return buckets
+}
+
+// HistogramOpts bundles the options for creating a Histogram metric. It is
+// mandatory to set Name and Help to a non-empty string. All other fields are
+// optional and can safely be left at their zero value.
+type HistogramOpts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Histogram (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the Histogram must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this Histogram. Mandatory!
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this
+	// Histogram. Histograms with the same fully-qualified name must have the
+	// same label names in their ConstLabels.
+	//
+	// Note that in most cases, labels have a value that varies during the
+	// lifetime of a process. Those labels are usually managed with a
+	// HistogramVec. ConstLabels serve only special purposes. One is for the
+	// special case where the value of a label does not change during the
+	// lifetime of a process, e.g. if the revision of the running binary is
+	// put into a label. Another, more advanced purpose is if more than one
+	// Collector needs to collect Histograms with the same fully-qualified
+	// name. In that case, those Summaries must differ in the values of
+	// their ConstLabels. See the Collector examples.
+	//
+	// If the value of a label never changes (not even between binaries),
+	// that label most likely should not be a label at all (but part of the
+	// metric name).
+	ConstLabels Labels
+
+	// Buckets defines the buckets into which observations are counted. Each
+	// element in the slice is the upper inclusive bound of a bucket. The
+	// values must be sorted in strictly increasing order. There is no need
+	// to add a highest bucket with +Inf bound, it will be added
+	// implicitly. The default value is DefBuckets.
+	Buckets []float64
+}
+
+// NewHistogram creates a new Histogram based on the provided HistogramOpts. It
+// panics if the buckets in HistogramOpts are not in strictly increasing order.
+func NewHistogram(opts HistogramOpts) Histogram {
+	return newHistogram(
+		NewDesc(
+			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+			opts.Help,
+			nil,
+			opts.ConstLabels,
+		),
+		opts,
+	)
+}
+
+func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogram {
+	if len(desc.variableLabels) != len(labelValues) {
+		panic(errInconsistentCardinality)
+	}
+
+	for _, n := range desc.variableLabels {
+		if n == bucketLabel {
+			panic(errBucketLabelNotAllowed)
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == bucketLabel {
+			panic(errBucketLabelNotAllowed)
+		}
+	}
+
+	if len(opts.Buckets) == 0 {
+		opts.Buckets = DefBuckets
+	}
+
+	h := &histogram{
+		desc:        desc,
+		upperBounds: opts.Buckets,
+		labelPairs:  makeLabelPairs(desc, labelValues),
+	}
+	for i, upperBound := range h.upperBounds {
+		if i < len(h.upperBounds)-1 {
+			if upperBound >= h.upperBounds[i+1] {
+				panic(fmt.Errorf(
+					"histogram buckets must be in increasing order: %f >= %f",
+					upperBound, h.upperBounds[i+1],
+				))
+			}
+		} else {
+			if math.IsInf(upperBound, +1) {
+				// The +Inf bucket is implicit. Remove it here.
+				h.upperBounds = h.upperBounds[:i]
+			}
+		}
+	}
+	// Finally we know the final length of h.upperBounds and can make counts.
+	h.counts = make([]uint64, len(h.upperBounds))
+
+	h.Init(h) // Init self-collection.
+	return h
+}
+
+type histogram struct {
+	// sumBits contains the bits of the float64 representing the sum of all
+	// observations. sumBits and count have to go first in the struct to
+	// guarantee alignment for atomic operations.
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	sumBits uint64
+	count   uint64
+
+	SelfCollector
+	// Note that there is no mutex required.
+
+	desc *Desc
+
+	upperBounds []float64
+	counts      []uint64
+
+	labelPairs []*dto.LabelPair
+}
+
+func (h *histogram) Desc() *Desc {
+	return h.desc
+}
+
+func (h *histogram) Observe(v float64) {
+	// TODO(beorn7): For small numbers of buckets (<30), a linear search is
+	// slightly faster than the binary search. If we really care, we could
+	// switch from one search strategy to the other depending on the number
+	// of buckets.
+	//
+	// Microbenchmarks (BenchmarkHistogramNoLabels):
+	// 11 buckets: 38.3 ns/op linear - binary 48.7 ns/op
+	// 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op
+	// 300 buckets: 154 ns/op linear - binary 61.6 ns/op
+	i := sort.SearchFloat64s(h.upperBounds, v)
+	if i < len(h.counts) {
+		atomic.AddUint64(&h.counts[i], 1)
+	}
+	atomic.AddUint64(&h.count, 1)
+	for {
+		oldBits := atomic.LoadUint64(&h.sumBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+		if atomic.CompareAndSwapUint64(&h.sumBits, oldBits, newBits) {
+			break
+		}
+	}
+}
+
+func (h *histogram) Write(out *dto.Metric) error {
+	his := &dto.Histogram{}
+	buckets := make([]*dto.Bucket, len(h.upperBounds))
+
+	his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&h.sumBits)))
+	his.SampleCount = proto.Uint64(atomic.LoadUint64(&h.count))
+	var count uint64
+	for i, upperBound := range h.upperBounds {
+		count += atomic.LoadUint64(&h.counts[i])
+		buckets[i] = &dto.Bucket{
+			CumulativeCount: proto.Uint64(count),
+			UpperBound:      proto.Float64(upperBound),
+		}
+	}
+	his.Bucket = buckets
+	out.Histogram = his
+	out.Label = h.labelPairs
+	return nil
+}
+
+// HistogramVec is a Collector that bundles a set of Histograms that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. HTTP request latencies, partitioned by status code and method). Create
+// instances with NewHistogramVec.
+type HistogramVec struct {
+	MetricVec
+}
+
+// NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &HistogramVec{
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newHistogram(desc, opts, lvs...)
+			},
+		},
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Histogram and not a
+// Metric so that no type conversion is required.
+func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Histogram, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Histogram), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Histogram and not a Metric so that no
+// type conversion is required.
+func (m *HistogramVec) GetMetricWith(labels Labels) (Histogram, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Histogram), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Observe(42.21)
+func (m *HistogramVec) WithLabelValues(lvs ...string) Histogram {
+	return m.MetricVec.WithLabelValues(lvs...).(Histogram)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
+func (m *HistogramVec) With(labels Labels) Histogram {
+	return m.MetricVec.With(labels).(Histogram)
+}
+
+type constHistogram struct {
+	desc       *Desc
+	count      uint64
+	sum        float64
+	buckets    map[float64]uint64
+	labelPairs []*dto.LabelPair
+}
+
+func (h *constHistogram) Desc() *Desc {
+	return h.desc
+}
+
+func (h *constHistogram) Write(out *dto.Metric) error {
+	his := &dto.Histogram{}
+	buckets := make([]*dto.Bucket, 0, len(h.buckets))
+
+	his.SampleCount = proto.Uint64(h.count)
+	his.SampleSum = proto.Float64(h.sum)
+
+	for upperBound, count := range h.buckets {
+		buckets = append(buckets, &dto.Bucket{
+			CumulativeCount: proto.Uint64(count),
+			UpperBound:      proto.Float64(upperBound),
+		})
+	}
+
+	if len(buckets) > 0 {
+		sort.Sort(buckSort(buckets))
+	}
+	his.Bucket = buckets
+
+	out.Histogram = his
+	out.Label = h.labelPairs
+
+	return nil
+}
+
+// NewConstHistogram returns a metric representing a Prometheus histogram with
+// fixed values for the count, sum, and bucket counts. As those parameters
+// cannot be changed, the returned value does not implement the Histogram
+// interface (but only the Metric interface). Users of this package will not
+// have much use for it in regular operations. However, when implementing custom
+// Collectors, it is useful as a throw-away metric that is generated on the fly
+// to send it to Prometheus in the Collect method.
+//
+// buckets is a map of upper bounds to cumulative counts, excluding the +Inf
+// bucket.
+//
+// NewConstHistogram returns an error if the length of labelValues is not
+// consistent with the variable labels in Desc.
+func NewConstHistogram(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	buckets map[float64]uint64,
+	labelValues ...string,
+) (Metric, error) {
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
+	}
+	return &constHistogram{
+		desc:       desc,
+		count:      count,
+		sum:        sum,
+		buckets:    buckets,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstHistogram is a version of NewConstHistogram that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstHistogram(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	buckets map[float64]uint64,
+	labelValues ...string,
+) Metric {
+	m, err := NewConstHistogram(desc, count, sum, buckets, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
+
+type buckSort []*dto.Bucket
+
+func (s buckSort) Len() int {
+	return len(s)
+}
+
+func (s buckSort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s buckSort) Less(i, j int) bool {
+	return s[i].GetUpperBound() < s[j].GetUpperBound()
+}

vendor/github.com/prometheus/client_golang/prometheus/http.go

@@ -0,0 +1,361 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var instLabels = []string{"method", "code"}
+
+type nower interface {
+	Now() time.Time
+}
+
+type nowFunc func() time.Time
+
+func (n nowFunc) Now() time.Time {
+	return n()
+}
+
+var now nower = nowFunc(func() time.Time {
+	return time.Now()
+})
+
+func nowSeries(t ...time.Time) nower {
+	return nowFunc(func() time.Time {
+		defer func() {
+			t = t[1:]
+		}()
+
+		return t[0]
+	})
+}
+
+// InstrumentHandler wraps the given HTTP handler for instrumentation. It
+// registers four metric collectors (if not already done) and reports HTTP
+// metrics to the (newly or already) registered collectors: http_requests_total
+// (CounterVec), http_request_duration_microseconds (Summary),
+// http_request_size_bytes (Summary), http_response_size_bytes (Summary). Each
+// has a constant label named "handler" with the provided handlerName as
+// value. http_requests_total is a metric vector partitioned by HTTP method
+// (label name "method") and HTTP status code (label name "code").
+func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
+	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
+}
+
+// InstrumentHandlerFunc wraps the given function for instrumentation. It
+// otherwise works in the same way as InstrumentHandler.
+func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	return InstrumentHandlerFuncWithOpts(
+		SummaryOpts{
+			Subsystem:   "http",
+			ConstLabels: Labels{"handler": handlerName},
+		},
+		handlerFunc,
+	)
+}
+
+// InstrumentHandlerWithOpts works like InstrumentHandler but provides more
+// flexibility (at the cost of a more complex call syntax). As
+// InstrumentHandler, this function registers four metric collectors, but it
+// uses the provided SummaryOpts to create them. However, the fields "Name" and
+// "Help" in the SummaryOpts are ignored. "Name" is replaced by
+// "requests_total", "request_duration_microseconds", "request_size_bytes", and
+// "response_size_bytes", respectively. "Help" is replaced by an appropriate
+// help string. The names of the variable labels of the http_requests_total
+// CounterVec are "method" (get, post, etc.), and "code" (HTTP status code).
+//
+// If InstrumentHandlerWithOpts is called as follows, it mimics exactly the
+// behavior of InstrumentHandler:
+//
+//     prometheus.InstrumentHandlerWithOpts(
+//         prometheus.SummaryOpts{
+//              Subsystem:   "http",
+//              ConstLabels: prometheus.Labels{"handler": handlerName},
+//         },
+//         handler,
+//     )
+//
+// Technical detail: "requests_total" is a CounterVec, not a SummaryVec, so it
+// cannot use SummaryOpts. Instead, a CounterOpts struct is created internally,
+// and all its fields are set to the equally named fields in the provided
+// SummaryOpts.
+func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
+	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
+}
+
+// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc but provides
+// more flexibility (at the cost of a more complex call syntax). See
+// InstrumentHandlerWithOpts for details how the provided SummaryOpts are used.
+func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	reqCnt := NewCounterVec(
+		CounterOpts{
+			Namespace:   opts.Namespace,
+			Subsystem:   opts.Subsystem,
+			Name:        "requests_total",
+			Help:        "Total number of HTTP requests made.",
+			ConstLabels: opts.ConstLabels,
+		},
+		instLabels,
+	)
+
+	opts.Name = "request_duration_microseconds"
+	opts.Help = "The HTTP request latencies in microseconds."
+	reqDur := NewSummary(opts)
+
+	opts.Name = "request_size_bytes"
+	opts.Help = "The HTTP request sizes in bytes."
+	reqSz := NewSummary(opts)
+
+	opts.Name = "response_size_bytes"
+	opts.Help = "The HTTP response sizes in bytes."
+	resSz := NewSummary(opts)
+
+	regReqCnt := MustRegisterOrGet(reqCnt).(*CounterVec)
+	regReqDur := MustRegisterOrGet(reqDur).(Summary)
+	regReqSz := MustRegisterOrGet(reqSz).(Summary)
+	regResSz := MustRegisterOrGet(resSz).(Summary)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		now := time.Now()
+
+		delegate := &responseWriterDelegator{ResponseWriter: w}
+		out := make(chan int)
+		urlLen := 0
+		if r.URL != nil {
+			urlLen = len(r.URL.String())
+		}
+		go computeApproximateRequestSize(r, out, urlLen)
+
+		_, cn := w.(http.CloseNotifier)
+		_, fl := w.(http.Flusher)
+		_, hj := w.(http.Hijacker)
+		_, rf := w.(io.ReaderFrom)
+		var rw http.ResponseWriter
+		if cn && fl && hj && rf {
+			rw = &fancyResponseWriterDelegator{delegate}
+		} else {
+			rw = delegate
+		}
+		handlerFunc(rw, r)
+
+		elapsed := float64(time.Since(now)) / float64(time.Microsecond)
+
+		method := sanitizeMethod(r.Method)
+		code := sanitizeCode(delegate.status)
+		regReqCnt.WithLabelValues(method, code).Inc()
+		regReqDur.Observe(elapsed)
+		regResSz.Observe(float64(delegate.written))
+		regReqSz.Observe(float64(<-out))
+	})
+}
+
+func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
+	s += len(r.Method)
+	s += len(r.Proto)
+	for name, values := range r.Header {
+		s += len(name)
+		for _, value := range values {
+			s += len(value)
+		}
+	}
+	s += len(r.Host)
+
+	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
+
+	if r.ContentLength != -1 {
+		s += int(r.ContentLength)
+	}
+	out <- s
+}
+
+type responseWriterDelegator struct {
+	http.ResponseWriter
+
+	handler, method string
+	status          int
+	written         int64
+	wroteHeader     bool
+}
+
+func (r *responseWriterDelegator) WriteHeader(code int) {
+	r.status = code
+	r.wroteHeader = true
+	r.ResponseWriter.WriteHeader(code)
+}
+
+func (r *responseWriterDelegator) Write(b []byte) (int, error) {
+	if !r.wroteHeader {
+		r.WriteHeader(http.StatusOK)
+	}
+	n, err := r.ResponseWriter.Write(b)
+	r.written += int64(n)
+	return n, err
+}
+
+type fancyResponseWriterDelegator struct {
+	*responseWriterDelegator
+}
+
+func (f *fancyResponseWriterDelegator) CloseNotify() <-chan bool {
+	return f.ResponseWriter.(http.CloseNotifier).CloseNotify()
+}
+
+func (f *fancyResponseWriterDelegator) Flush() {
+	f.ResponseWriter.(http.Flusher).Flush()
+}
+
+func (f *fancyResponseWriterDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return f.ResponseWriter.(http.Hijacker).Hijack()
+}
+
+func (f *fancyResponseWriterDelegator) ReadFrom(r io.Reader) (int64, error) {
+	if !f.wroteHeader {
+		f.WriteHeader(http.StatusOK)
+	}
+	n, err := f.ResponseWriter.(io.ReaderFrom).ReadFrom(r)
+	f.written += n
+	return n, err
+}
+
+func sanitizeMethod(m string) string {
+	switch m {
+	case "GET", "get":
+		return "get"
+	case "PUT", "put":
+		return "put"
+	case "HEAD", "head":
+		return "head"
+	case "POST", "post":
+		return "post"
+	case "DELETE", "delete":
+		return "delete"
+	case "CONNECT", "connect":
+		return "connect"
+	case "OPTIONS", "options":
+		return "options"
+	case "NOTIFY", "notify":
+		return "notify"
+	default:
+		return strings.ToLower(m)
+	}
+}
+
+func sanitizeCode(s int) string {
+	switch s {
+	case 100:
+		return "100"
+	case 101:
+		return "101"
+
+	case 200:
+		return "200"
+	case 201:
+		return "201"
+	case 202:
+		return "202"
+	case 203:
+		return "203"
+	case 204:
+		return "204"
+	case 205:
+		return "205"
+	case 206:
+		return "206"
+
+	case 300:
+		return "300"
+	case 301:
+		return "301"
+	case 302:
+		return "302"
+	case 304:
+		return "304"
+	case 305:
+		return "305"
+	case 307:
+		return "307"
+
+	case 400:
+		return "400"
+	case 401:
+		return "401"
+	case 402:
+		return "402"
+	case 403:
+		return "403"
+	case 404:
+		return "404"
+	case 405:
+		return "405"
+	case 406:
+		return "406"
+	case 407:
+		return "407"
+	case 408:
+		return "408"
+	case 409:
+		return "409"
+	case 410:
+		return "410"
+	case 411:
+		return "411"
+	case 412:
+		return "412"
+	case 413:
+		return "413"
+	case 414:
+		return "414"
+	case 415:
+		return "415"
+	case 416:
+		return "416"
+	case 417:
+		return "417"
+	case 418:
+		return "418"
+
+	case 500:
+		return "500"
+	case 501:
+		return "501"
+	case 502:
+		return "502"
+	case 503:
+		return "503"
+	case 504:
+		return "504"
+	case 505:
+		return "505"
+
+	case 428:
+		return "428"
+	case 429:
+		return "429"
+	case 431:
+		return "431"
+	case 511:
+		return "511"
+
+	default:
+		return strconv.Itoa(s)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/metric.go

@@ -0,0 +1,166 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+const separatorByte byte = 255
+
+// A Metric models a single sample value with its meta data being exported to
+// Prometheus. Implementers of Metric in this package inclued Gauge, Counter,
+// Untyped, and Summary. Users can implement their own Metric types, but that
+// should be rarely needed. See the example for SelfCollector, which is also an
+// example for a user-implemented Metric.
+type Metric interface {
+	// Desc returns the descriptor for the Metric. This method idempotently
+	// returns the same descriptor throughout the lifetime of the
+	// Metric. The returned descriptor is immutable by contract. A Metric
+	// unable to describe itself must return an invalid descriptor (created
+	// with NewInvalidDesc).
+	Desc() *Desc
+	// Write encodes the Metric into a "Metric" Protocol Buffer data
+	// transmission object.
+	//
+	// Implementers of custom Metric types must observe concurrency safety
+	// as reads of this metric may occur at any time, and any blocking
+	// occurs at the expense of total performance of rendering all
+	// registered metrics. Ideally Metric implementations should support
+	// concurrent readers.
+	//
+	// The Prometheus client library attempts to minimize memory allocations
+	// and will provide a pre-existing reset dto.Metric pointer. Prometheus
+	// may recycle the dto.Metric proto message, so Metric implementations
+	// should just populate the provided dto.Metric and then should not keep
+	// any reference to it.
+	//
+	// While populating dto.Metric, labels must be sorted lexicographically.
+	// (Implementers may find LabelPairSorter useful for that.)
+	Write(*dto.Metric) error
+}
+
+// Opts bundles the options for creating most Metric types. Each metric
+// implementation XXX has its own XXXOpts type, but in most cases, it is just be
+// an alias of this type (which might change when the requirement arises.)
+//
+// It is mandatory to set Name and Help to a non-empty string. All other fields
+// are optional and can safely be left at their zero value.
+type Opts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Metric (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the metric must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this metric. Mandatory!
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
+	// with the same fully-qualified name must have the same label names in
+	// their ConstLabels.
+	//
+	// Note that in most cases, labels have a value that varies during the
+	// lifetime of a process. Those labels are usually managed with a metric
+	// vector collector (like CounterVec, GaugeVec, UntypedVec). ConstLabels
+	// serve only special purposes. One is for the special case where the
+	// value of a label does not change during the lifetime of a process,
+	// e.g. if the revision of the running binary is put into a
+	// label. Another, more advanced purpose is if more than one Collector
+	// needs to collect Metrics with the same fully-qualified name. In that
+	// case, those Metrics must differ in the values of their
+	// ConstLabels. See the Collector examples.
+	//
+	// If the value of a label never changes (not even between binaries),
+	// that label most likely should not be a label at all (but part of the
+	// metric name).
+	ConstLabels Labels
+}
+
+// BuildFQName joins the given three name components by "_". Empty name
+// components are ignored. If the name parameter itself is empty, an empty
+// string is returned, no matter what. Metric implementations included in this
+// library use this function internally to generate the fully-qualified metric
+// name from the name component in their Opts. Users of the library will only
+// need this function if they implement their own Metric or instantiate a Desc
+// (with NewDesc) directly.
+func BuildFQName(namespace, subsystem, name string) string {
+	if name == "" {
+		return ""
+	}
+	switch {
+	case namespace != "" && subsystem != "":
+		return strings.Join([]string{namespace, subsystem, name}, "_")
+	case namespace != "":
+		return strings.Join([]string{namespace, name}, "_")
+	case subsystem != "":
+		return strings.Join([]string{subsystem, name}, "_")
+	}
+	return name
+}
+
+// LabelPairSorter implements sort.Interface. It is used to sort a slice of
+// dto.LabelPair pointers. This is useful for implementing the Write method of
+// custom metrics.
+type LabelPairSorter []*dto.LabelPair
+
+func (s LabelPairSorter) Len() int {
+	return len(s)
+}
+
+func (s LabelPairSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s LabelPairSorter) Less(i, j int) bool {
+	return s[i].GetName() < s[j].GetName()
+}
+
+type hashSorter []uint64
+
+func (s hashSorter) Len() int {
+	return len(s)
+}
+
+func (s hashSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s hashSorter) Less(i, j int) bool {
+	return s[i] < s[j]
+}
+
+type invalidMetric struct {
+	desc *Desc
+	err  error
+}
+
+// NewInvalidMetric returns a metric whose Write method always returns the
+// provided error. It is useful if a Collector finds itself unable to collect
+// a metric and wishes to report an error to the registry.
+func NewInvalidMetric(desc *Desc, err error) Metric {
+	return &invalidMetric{desc, err}
+}
+
+func (m *invalidMetric) Desc() *Desc { return m.desc }
+
+func (m *invalidMetric) Write(*dto.Metric) error { return m.err }

vendor/github.com/prometheus/client_golang/prometheus/process_collector.go

@@ -0,0 +1,142 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import "github.com/prometheus/procfs"
+
+type processCollector struct {
+	pid             int
+	collectFn       func(chan<- Metric)
+	pidFn           func() (int, error)
+	cpuTotal        Counter
+	openFDs, maxFDs Gauge
+	vsize, rss      Gauge
+	startTime       Gauge
+}
+
+// NewProcessCollector returns a collector which exports the current state of
+// process metrics including cpu, memory and file descriptor usage as well as
+// the process start time for the given process id under the given namespace.
+func NewProcessCollector(pid int, namespace string) *processCollector {
+	return NewProcessCollectorPIDFn(
+		func() (int, error) { return pid, nil },
+		namespace,
+	)
+}
+
+// NewProcessCollectorPIDFn returns a collector which exports the current state
+// of process metrics including cpu, memory and file descriptor usage as well
+// as the process start time under the given namespace. The given pidFn is
+// called on each collect and is used to determine the process to export
+// metrics for.
+func NewProcessCollectorPIDFn(
+	pidFn func() (int, error),
+	namespace string,
+) *processCollector {
+	c := processCollector{
+		pidFn:     pidFn,
+		collectFn: func(chan<- Metric) {},
+
+		cpuTotal: NewCounter(CounterOpts{
+			Namespace: namespace,
+			Name:      "process_cpu_seconds_total",
+			Help:      "Total user and system CPU time spent in seconds.",
+		}),
+		openFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_open_fds",
+			Help:      "Number of open file descriptors.",
+		}),
+		maxFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_max_fds",
+			Help:      "Maximum number of open file descriptors.",
+		}),
+		vsize: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_virtual_memory_bytes",
+			Help:      "Virtual memory size in bytes.",
+		}),
+		rss: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_resident_memory_bytes",
+			Help:      "Resident memory size in bytes.",
+		}),
+		startTime: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_start_time_seconds",
+			Help:      "Start time of the process since unix epoch in seconds.",
+		}),
+	}
+
+	// Set up process metric collection if supported by the runtime.
+	if _, err := procfs.NewStat(); err == nil {
+		c.collectFn = c.processCollect
+	}
+
+	return &c
+}
+
+// Describe returns all descriptions of the collector.
+func (c *processCollector) Describe(ch chan<- *Desc) {
+	ch <- c.cpuTotal.Desc()
+	ch <- c.openFDs.Desc()
+	ch <- c.maxFDs.Desc()
+	ch <- c.vsize.Desc()
+	ch <- c.rss.Desc()
+	ch <- c.startTime.Desc()
+}
+
+// Collect returns the current state of all metrics of the collector.
+func (c *processCollector) Collect(ch chan<- Metric) {
+	c.collectFn(ch)
+}
+
+// TODO(ts): Bring back error reporting by reverting 7faf9e7 as soon as the
+// client allows users to configure the error behavior.
+func (c *processCollector) processCollect(ch chan<- Metric) {
+	pid, err := c.pidFn()
+	if err != nil {
+		return
+	}
+
+	p, err := procfs.NewProc(pid)
+	if err != nil {
+		return
+	}
+
+	if stat, err := p.NewStat(); err == nil {
+		c.cpuTotal.Set(stat.CPUTime())
+		ch <- c.cpuTotal
+		c.vsize.Set(float64(stat.VirtualMemory()))
+		ch <- c.vsize
+		c.rss.Set(float64(stat.ResidentMemory()))
+		ch <- c.rss
+
+		if startTime, err := stat.StartTime(); err == nil {
+			c.startTime.Set(startTime)
+			ch <- c.startTime
+		}
+	}
+
+	if fds, err := p.FileDescriptorsLen(); err == nil {
+		c.openFDs.Set(float64(fds))
+		ch <- c.openFDs
+	}
+
+	if limits, err := p.NewLimits(); err == nil {
+		c.maxFDs.Set(float64(limits.OpenFiles))
+		ch <- c.maxFDs
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/push.go

@@ -0,0 +1,65 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package prometheus
+
+// Push triggers a metric collection by the default registry and pushes all
+// collected metrics to the Pushgateway specified by addr. See the Pushgateway
+// documentation for detailed implications of the job and instance
+// parameter. instance can be left empty. You can use just host:port or ip:port
+// as url, in which case 'http://' is added automatically. You can also include
+// the schema in the URL. However, do not include the '/metrics/jobs/...' part.
+//
+// Note that all previously pushed metrics with the same job and instance will
+// be replaced with the metrics pushed by this call. (It uses HTTP method 'PUT'
+// to push to the Pushgateway.)
+func Push(job, instance, url string) error {
+	return defRegistry.Push(job, instance, url, "PUT")
+}
+
+// PushAdd works like Push, but only previously pushed metrics with the same
+// name (and the same job and instance) will be replaced. (It uses HTTP method
+// 'POST' to push to the Pushgateway.)
+func PushAdd(job, instance, url string) error {
+	return defRegistry.Push(job, instance, url, "POST")
+}
+
+// PushCollectors works like Push, but it does not collect from the default
+// registry. Instead, it collects from the provided collectors. It is a
+// convenient way to push only a few metrics.
+func PushCollectors(job, instance, url string, collectors ...Collector) error {
+	return pushCollectors(job, instance, url, "PUT", collectors...)
+}
+
+// PushAddCollectors works like PushAdd, but it does not collect from the
+// default registry. Instead, it collects from the provided collectors. It is a
+// convenient way to push only a few metrics.
+func PushAddCollectors(job, instance, url string, collectors ...Collector) error {
+	return pushCollectors(job, instance, url, "POST", collectors...)
+}
+
+func pushCollectors(job, instance, url, method string, collectors ...Collector) error {
+	r := newRegistry()
+	for _, collector := range collectors {
+		if _, err := r.Register(collector); err != nil {
+			return err
+		}
+	}
+	return r.Push(job, instance, url, method)
+}

vendor/github.com/prometheus/client_golang/prometheus/registry.go

@@ -0,0 +1,726 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package prometheus
+
+import (
+	"bytes"
+	"compress/gzip"
+	"errors"
+	"fmt"
+	"hash/fnv"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"sort"
+	"strings"
+	"sync"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/expfmt"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+var (
+	defRegistry   = newDefaultRegistry()
+	errAlreadyReg = errors.New("duplicate metrics collector registration attempted")
+)
+
+// Constants relevant to the HTTP interface.
+const (
+	// APIVersion is the version of the format of the exported data.  This
+	// will match this library's version, which subscribes to the Semantic
+	// Versioning scheme.
+	APIVersion = "0.0.4"
+
+	// DelimitedTelemetryContentType is the content type set on telemetry
+	// data responses in delimited protobuf format.
+	DelimitedTelemetryContentType = `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`
+	// TextTelemetryContentType is the content type set on telemetry data
+	// responses in text format.
+	TextTelemetryContentType = `text/plain; version=` + APIVersion
+	// ProtoTextTelemetryContentType is the content type set on telemetry
+	// data responses in protobuf text format.  (Only used for debugging.)
+	ProtoTextTelemetryContentType = `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=text`
+	// ProtoCompactTextTelemetryContentType is the content type set on
+	// telemetry data responses in protobuf compact text format.  (Only used
+	// for debugging.)
+	ProtoCompactTextTelemetryContentType = `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=compact-text`
+
+	// Constants for object pools.
+	numBufs           = 4
+	numMetricFamilies = 1000
+	numMetrics        = 10000
+
+	// Capacity for the channel to collect metrics and descriptors.
+	capMetricChan = 1000
+	capDescChan   = 10
+
+	contentTypeHeader     = "Content-Type"
+	contentLengthHeader   = "Content-Length"
+	contentEncodingHeader = "Content-Encoding"
+
+	acceptEncodingHeader = "Accept-Encoding"
+	acceptHeader         = "Accept"
+)
+
+// Handler returns the HTTP handler for the global Prometheus registry. It is
+// already instrumented with InstrumentHandler (using "prometheus" as handler
+// name). Usually the handler is used to handle the "/metrics" endpoint.
+func Handler() http.Handler {
+	return InstrumentHandler("prometheus", defRegistry)
+}
+
+// UninstrumentedHandler works in the same way as Handler, but the returned HTTP
+// handler is not instrumented. This is useful if no instrumentation is desired
+// (for whatever reason) or if the instrumentation has to happen with a
+// different handler name (or with a different instrumentation approach
+// altogether). See the InstrumentHandler example.
+func UninstrumentedHandler() http.Handler {
+	return defRegistry
+}
+
+// Register registers a new Collector to be included in metrics collection. It
+// returns an error if the descriptors provided by the Collector are invalid or
+// if they - in combination with descriptors of already registered Collectors -
+// do not fulfill the consistency and uniqueness criteria described in the Desc
+// documentation.
+//
+// Do not register the same Collector multiple times concurrently. (Registering
+// the same Collector twice would result in an error anyway, but on top of that,
+// it is not safe to do so concurrently.)
+func Register(m Collector) error {
+	_, err := defRegistry.Register(m)
+	return err
+}
+
+// MustRegister works like Register but panics where Register would have
+// returned an error.
+func MustRegister(m Collector) {
+	err := Register(m)
+	if err != nil {
+		panic(err)
+	}
+}
+
+// RegisterOrGet works like Register but does not return an error if a Collector
+// is registered that equals a previously registered Collector. (Two Collectors
+// are considered equal if their Describe method yields the same set of
+// descriptors.) Instead, the previously registered Collector is returned (which
+// is helpful if the new and previously registered Collectors are equal but not
+// identical, i.e. not pointers to the same object).
+//
+// As for Register, it is still not safe to call RegisterOrGet with the same
+// Collector multiple times concurrently.
+func RegisterOrGet(m Collector) (Collector, error) {
+	return defRegistry.RegisterOrGet(m)
+}
+
+// MustRegisterOrGet works like Register but panics where RegisterOrGet would
+// have returned an error.
+func MustRegisterOrGet(m Collector) Collector {
+	existing, err := RegisterOrGet(m)
+	if err != nil {
+		panic(err)
+	}
+	return existing
+}
+
+// Unregister unregisters the Collector that equals the Collector passed in as
+// an argument. (Two Collectors are considered equal if their Describe method
+// yields the same set of descriptors.) The function returns whether a Collector
+// was unregistered.
+func Unregister(c Collector) bool {
+	return defRegistry.Unregister(c)
+}
+
+// SetMetricFamilyInjectionHook sets a function that is called whenever metrics
+// are collected. The hook function must be set before metrics collection begins
+// (i.e. call SetMetricFamilyInjectionHook before setting the HTTP handler.) The
+// MetricFamily protobufs returned by the hook function are merged with the
+// metrics collected in the usual way.
+//
+// This is a way to directly inject MetricFamily protobufs managed and owned by
+// the caller. The caller has full responsibility. As no registration of the
+// injected metrics has happened, there is no descriptor to check against, and
+// there are no registration-time checks. If collect-time checks are disabled
+// (see function EnableCollectChecks), no sanity checks are performed on the
+// returned protobufs at all. If collect-checks are enabled, type and uniqueness
+// checks are performed, but no further consistency checks (which would require
+// knowledge of a metric descriptor).
+//
+// Sorting concerns: The caller is responsible for sorting the label pairs in
+// each metric. However, the order of metrics will be sorted by the registry as
+// it is required anyway after merging with the metric families collected
+// conventionally.
+//
+// The function must be callable at any time and concurrently.
+func SetMetricFamilyInjectionHook(hook func() []*dto.MetricFamily) {
+	defRegistry.metricFamilyInjectionHook = hook
+}
+
+// PanicOnCollectError sets the behavior whether a panic is caused upon an error
+// while metrics are collected and served to the HTTP endpoint. By default, an
+// internal server error (status code 500) is served with an error message.
+func PanicOnCollectError(b bool) {
+	defRegistry.panicOnCollectError = b
+}
+
+// EnableCollectChecks enables (or disables) additional consistency checks
+// during metrics collection. These additional checks are not enabled by default
+// because they inflict a performance penalty and the errors they check for can
+// only happen if the used Metric and Collector types have internal programming
+// errors. It can be helpful to enable these checks while working with custom
+// Collectors or Metrics whose correctness is not well established yet.
+func EnableCollectChecks(b bool) {
+	defRegistry.collectChecksEnabled = b
+}
+
+// encoder is a function that writes a dto.MetricFamily to an io.Writer in a
+// certain encoding. It returns the number of bytes written and any error
+// encountered.  Note that pbutil.WriteDelimited and pbutil.MetricFamilyToText
+// are encoders.
+type encoder func(io.Writer, *dto.MetricFamily) (int, error)
+
+type registry struct {
+	mtx                       sync.RWMutex
+	collectorsByID            map[uint64]Collector // ID is a hash of the descIDs.
+	descIDs                   map[uint64]struct{}
+	dimHashesByName           map[string]uint64
+	bufPool                   chan *bytes.Buffer
+	metricFamilyPool          chan *dto.MetricFamily
+	metricPool                chan *dto.Metric
+	metricFamilyInjectionHook func() []*dto.MetricFamily
+
+	panicOnCollectError, collectChecksEnabled bool
+}
+
+func (r *registry) Register(c Collector) (Collector, error) {
+	descChan := make(chan *Desc, capDescChan)
+	go func() {
+		c.Describe(descChan)
+		close(descChan)
+	}()
+
+	newDescIDs := map[uint64]struct{}{}
+	newDimHashesByName := map[string]uint64{}
+	var collectorID uint64 // Just a sum of all desc IDs.
+	var duplicateDescErr error
+
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	// Coduct various tests...
+	for desc := range descChan {
+
+		// Is the descriptor valid at all?
+		if desc.err != nil {
+			return c, fmt.Errorf("descriptor %s is invalid: %s", desc, desc.err)
+		}
+
+		// Is the descID unique?
+		// (In other words: Is the fqName + constLabel combination unique?)
+		if _, exists := r.descIDs[desc.id]; exists {
+			duplicateDescErr = fmt.Errorf("descriptor %s already exists with the same fully-qualified name and const label values", desc)
+		}
+		// If it is not a duplicate desc in this collector, add it to
+		// the collectorID.  (We allow duplicate descs within the same
+		// collector, but their existence must be a no-op.)
+		if _, exists := newDescIDs[desc.id]; !exists {
+			newDescIDs[desc.id] = struct{}{}
+			collectorID += desc.id
+		}
+
+		// Are all the label names and the help string consistent with
+		// previous descriptors of the same name?
+		// First check existing descriptors...
+		if dimHash, exists := r.dimHashesByName[desc.fqName]; exists {
+			if dimHash != desc.dimHash {
+				return nil, fmt.Errorf("a previously registered descriptor with the same fully-qualified name as %s has different label names or a different help string", desc)
+			}
+		} else {
+			// ...then check the new descriptors already seen.
+			if dimHash, exists := newDimHashesByName[desc.fqName]; exists {
+				if dimHash != desc.dimHash {
+					return nil, fmt.Errorf("descriptors reported by collector have inconsistent label names or help strings for the same fully-qualified name, offender is %s", desc)
+				}
+			} else {
+				newDimHashesByName[desc.fqName] = desc.dimHash
+			}
+		}
+	}
+	// Did anything happen at all?
+	if len(newDescIDs) == 0 {
+		return nil, errors.New("collector has no descriptors")
+	}
+	if existing, exists := r.collectorsByID[collectorID]; exists {
+		return existing, errAlreadyReg
+	}
+	// If the collectorID is new, but at least one of the descs existed
+	// before, we are in trouble.
+	if duplicateDescErr != nil {
+		return nil, duplicateDescErr
+	}
+
+	// Only after all tests have passed, actually register.
+	r.collectorsByID[collectorID] = c
+	for hash := range newDescIDs {
+		r.descIDs[hash] = struct{}{}
+	}
+	for name, dimHash := range newDimHashesByName {
+		r.dimHashesByName[name] = dimHash
+	}
+	return c, nil
+}
+
+func (r *registry) RegisterOrGet(m Collector) (Collector, error) {
+	existing, err := r.Register(m)
+	if err != nil && err != errAlreadyReg {
+		return nil, err
+	}
+	return existing, nil
+}
+
+func (r *registry) Unregister(c Collector) bool {
+	descChan := make(chan *Desc, capDescChan)
+	go func() {
+		c.Describe(descChan)
+		close(descChan)
+	}()
+
+	descIDs := map[uint64]struct{}{}
+	var collectorID uint64 // Just a sum of the desc IDs.
+	for desc := range descChan {
+		if _, exists := descIDs[desc.id]; !exists {
+			collectorID += desc.id
+			descIDs[desc.id] = struct{}{}
+		}
+	}
+
+	r.mtx.RLock()
+	if _, exists := r.collectorsByID[collectorID]; !exists {
+		r.mtx.RUnlock()
+		return false
+	}
+	r.mtx.RUnlock()
+
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+
+	delete(r.collectorsByID, collectorID)
+	for id := range descIDs {
+		delete(r.descIDs, id)
+	}
+	// dimHashesByName is left untouched as those must be consistent
+	// throughout the lifetime of a program.
+	return true
+}
+
+func (r *registry) Push(job, instance, pushURL, method string) error {
+	if !strings.Contains(pushURL, "://") {
+		pushURL = "http://" + pushURL
+	}
+	pushURL = fmt.Sprintf("%s/metrics/jobs/%s", pushURL, url.QueryEscape(job))
+	if instance != "" {
+		pushURL += "/instances/" + url.QueryEscape(instance)
+	}
+	buf := r.getBuf()
+	defer r.giveBuf(buf)
+	if err := r.writePB(expfmt.NewEncoder(buf, expfmt.FmtProtoDelim)); err != nil {
+		if r.panicOnCollectError {
+			panic(err)
+		}
+		return err
+	}
+	req, err := http.NewRequest(method, pushURL, buf)
+	if err != nil {
+		return err
+	}
+	req.Header.Set(contentTypeHeader, DelimitedTelemetryContentType)
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != 202 {
+		return fmt.Errorf("unexpected status code %d while pushing to %s", resp.StatusCode, pushURL)
+	}
+	return nil
+}
+
+func (r *registry) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	contentType := expfmt.Negotiate(req.Header)
+	buf := r.getBuf()
+	defer r.giveBuf(buf)
+	writer, encoding := decorateWriter(req, buf)
+	if err := r.writePB(expfmt.NewEncoder(writer, contentType)); err != nil {
+		if r.panicOnCollectError {
+			panic(err)
+		}
+		http.Error(w, "An error has occurred:\n\n"+err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if closer, ok := writer.(io.Closer); ok {
+		closer.Close()
+	}
+	header := w.Header()
+	header.Set(contentTypeHeader, string(contentType))
+	header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
+	if encoding != "" {
+		header.Set(contentEncodingHeader, encoding)
+	}
+	w.Write(buf.Bytes())
+}
+
+func (r *registry) writePB(encoder expfmt.Encoder) error {
+	var metricHashes map[uint64]struct{}
+	if r.collectChecksEnabled {
+		metricHashes = make(map[uint64]struct{})
+	}
+	metricChan := make(chan Metric, capMetricChan)
+	wg := sync.WaitGroup{}
+
+	r.mtx.RLock()
+	metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName))
+
+	// Scatter.
+	// (Collectors could be complex and slow, so we call them all at once.)
+	wg.Add(len(r.collectorsByID))
+	go func() {
+		wg.Wait()
+		close(metricChan)
+	}()
+	for _, collector := range r.collectorsByID {
+		go func(collector Collector) {
+			defer wg.Done()
+			collector.Collect(metricChan)
+		}(collector)
+	}
+	r.mtx.RUnlock()
+
+	// Drain metricChan in case of premature return.
+	defer func() {
+		for _ = range metricChan {
+		}
+	}()
+
+	// Gather.
+	for metric := range metricChan {
+		// This could be done concurrently, too, but it required locking
+		// of metricFamiliesByName (and of metricHashes if checks are
+		// enabled). Most likely not worth it.
+		desc := metric.Desc()
+		metricFamily, ok := metricFamiliesByName[desc.fqName]
+		if !ok {
+			metricFamily = r.getMetricFamily()
+			defer r.giveMetricFamily(metricFamily)
+			metricFamily.Name = proto.String(desc.fqName)
+			metricFamily.Help = proto.String(desc.help)
+			metricFamiliesByName[desc.fqName] = metricFamily
+		}
+		dtoMetric := r.getMetric()
+		defer r.giveMetric(dtoMetric)
+		if err := metric.Write(dtoMetric); err != nil {
+			// TODO: Consider different means of error reporting so
+			// that a single erroneous metric could be skipped
+			// instead of blowing up the whole collection.
+			return fmt.Errorf("error collecting metric %v: %s", desc, err)
+		}
+		switch {
+		case metricFamily.Type != nil:
+			// Type already set. We are good.
+		case dtoMetric.Gauge != nil:
+			metricFamily.Type = dto.MetricType_GAUGE.Enum()
+		case dtoMetric.Counter != nil:
+			metricFamily.Type = dto.MetricType_COUNTER.Enum()
+		case dtoMetric.Summary != nil:
+			metricFamily.Type = dto.MetricType_SUMMARY.Enum()
+		case dtoMetric.Untyped != nil:
+			metricFamily.Type = dto.MetricType_UNTYPED.Enum()
+		case dtoMetric.Histogram != nil:
+			metricFamily.Type = dto.MetricType_HISTOGRAM.Enum()
+		default:
+			return fmt.Errorf("empty metric collected: %s", dtoMetric)
+		}
+		if r.collectChecksEnabled {
+			if err := r.checkConsistency(metricFamily, dtoMetric, desc, metricHashes); err != nil {
+				return err
+			}
+		}
+		metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
+	}
+
+	if r.metricFamilyInjectionHook != nil {
+		for _, mf := range r.metricFamilyInjectionHook() {
+			existingMF, exists := metricFamiliesByName[mf.GetName()]
+			if !exists {
+				metricFamiliesByName[mf.GetName()] = mf
+				if r.collectChecksEnabled {
+					for _, m := range mf.Metric {
+						if err := r.checkConsistency(mf, m, nil, metricHashes); err != nil {
+							return err
+						}
+					}
+				}
+				continue
+			}
+			for _, m := range mf.Metric {
+				if r.collectChecksEnabled {
+					if err := r.checkConsistency(existingMF, m, nil, metricHashes); err != nil {
+						return err
+					}
+				}
+				existingMF.Metric = append(existingMF.Metric, m)
+			}
+		}
+	}
+
+	// Now that MetricFamilies are all set, sort their Metrics
+	// lexicographically by their label values.
+	for _, mf := range metricFamiliesByName {
+		sort.Sort(metricSorter(mf.Metric))
+	}
+
+	// Write out MetricFamilies sorted by their name.
+	names := make([]string, 0, len(metricFamiliesByName))
+	for name := range metricFamiliesByName {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+
+	for _, name := range names {
+		if err := encoder.Encode(metricFamiliesByName[name]); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (r *registry) checkConsistency(metricFamily *dto.MetricFamily, dtoMetric *dto.Metric, desc *Desc, metricHashes map[uint64]struct{}) error {
+
+	// Type consistency with metric family.
+	if metricFamily.GetType() == dto.MetricType_GAUGE && dtoMetric.Gauge == nil ||
+		metricFamily.GetType() == dto.MetricType_COUNTER && dtoMetric.Counter == nil ||
+		metricFamily.GetType() == dto.MetricType_SUMMARY && dtoMetric.Summary == nil ||
+		metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil ||
+		metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil {
+		return fmt.Errorf(
+			"collected metric %s %s is not a %s",
+			metricFamily.GetName(), dtoMetric, metricFamily.GetType(),
+		)
+	}
+
+	// Is the metric unique (i.e. no other metric with the same name and the same label values)?
+	h := fnv.New64a()
+	var buf bytes.Buffer
+	buf.WriteString(metricFamily.GetName())
+	buf.WriteByte(separatorByte)
+	h.Write(buf.Bytes())
+	// Make sure label pairs are sorted. We depend on it for the consistency
+	// check. Label pairs must be sorted by contract. But the point of this
+	// method is to check for contract violations. So we better do the sort
+	// now.
+	sort.Sort(LabelPairSorter(dtoMetric.Label))
+	for _, lp := range dtoMetric.Label {
+		buf.Reset()
+		buf.WriteString(lp.GetValue())
+		buf.WriteByte(separatorByte)
+		h.Write(buf.Bytes())
+	}
+	metricHash := h.Sum64()
+	if _, exists := metricHashes[metricHash]; exists {
+		return fmt.Errorf(
+			"collected metric %s %s was collected before with the same name and label values",
+			metricFamily.GetName(), dtoMetric,
+		)
+	}
+	metricHashes[metricHash] = struct{}{}
+
+	if desc == nil {
+		return nil // Nothing left to check if we have no desc.
+	}
+
+	// Desc consistency with metric family.
+	if metricFamily.GetName() != desc.fqName {
+		return fmt.Errorf(
+			"collected metric %s %s has name %q but should have %q",
+			metricFamily.GetName(), dtoMetric, metricFamily.GetName(), desc.fqName,
+		)
+	}
+	if metricFamily.GetHelp() != desc.help {
+		return fmt.Errorf(
+			"collected metric %s %s has help %q but should have %q",
+			metricFamily.GetName(), dtoMetric, metricFamily.GetHelp(), desc.help,
+		)
+	}
+
+	// Is the desc consistent with the content of the metric?
+	lpsFromDesc := make([]*dto.LabelPair, 0, len(dtoMetric.Label))
+	lpsFromDesc = append(lpsFromDesc, desc.constLabelPairs...)
+	for _, l := range desc.variableLabels {
+		lpsFromDesc = append(lpsFromDesc, &dto.LabelPair{
+			Name: proto.String(l),
+		})
+	}
+	if len(lpsFromDesc) != len(dtoMetric.Label) {
+		return fmt.Errorf(
+			"labels in collected metric %s %s are inconsistent with descriptor %s",
+			metricFamily.GetName(), dtoMetric, desc,
+		)
+	}
+	sort.Sort(LabelPairSorter(lpsFromDesc))
+	for i, lpFromDesc := range lpsFromDesc {
+		lpFromMetric := dtoMetric.Label[i]
+		if lpFromDesc.GetName() != lpFromMetric.GetName() ||
+			lpFromDesc.Value != nil && lpFromDesc.GetValue() != lpFromMetric.GetValue() {
+			return fmt.Errorf(
+				"labels in collected metric %s %s are inconsistent with descriptor %s",
+				metricFamily.GetName(), dtoMetric, desc,
+			)
+		}
+	}
+
+	r.mtx.RLock() // Remaining checks need the read lock.
+	defer r.mtx.RUnlock()
+
+	// Is the desc registered?
+	if _, exist := r.descIDs[desc.id]; !exist {
+		return fmt.Errorf(
+			"collected metric %s %s with unregistered descriptor %s",
+			metricFamily.GetName(), dtoMetric, desc,
+		)
+	}
+
+	return nil
+}
+
+func (r *registry) getBuf() *bytes.Buffer {
+	select {
+	case buf := <-r.bufPool:
+		return buf
+	default:
+		return &bytes.Buffer{}
+	}
+}
+
+func (r *registry) giveBuf(buf *bytes.Buffer) {
+	buf.Reset()
+	select {
+	case r.bufPool <- buf:
+	default:
+	}
+}
+
+func (r *registry) getMetricFamily() *dto.MetricFamily {
+	select {
+	case mf := <-r.metricFamilyPool:
+		return mf
+	default:
+		return &dto.MetricFamily{}
+	}
+}
+
+func (r *registry) giveMetricFamily(mf *dto.MetricFamily) {
+	mf.Reset()
+	select {
+	case r.metricFamilyPool <- mf:
+	default:
+	}
+}
+
+func (r *registry) getMetric() *dto.Metric {
+	select {
+	case m := <-r.metricPool:
+		return m
+	default:
+		return &dto.Metric{}
+	}
+}
+
+func (r *registry) giveMetric(m *dto.Metric) {
+	m.Reset()
+	select {
+	case r.metricPool <- m:
+	default:
+	}
+}
+
+func newRegistry() *registry {
+	return &registry{
+		collectorsByID:   map[uint64]Collector{},
+		descIDs:          map[uint64]struct{}{},
+		dimHashesByName:  map[string]uint64{},
+		bufPool:          make(chan *bytes.Buffer, numBufs),
+		metricFamilyPool: make(chan *dto.MetricFamily, numMetricFamilies),
+		metricPool:       make(chan *dto.Metric, numMetrics),
+	}
+}
+
+func newDefaultRegistry() *registry {
+	r := newRegistry()
+	r.Register(NewProcessCollector(os.Getpid(), ""))
+	r.Register(NewGoCollector())
+	return r
+}
+
+// decorateWriter wraps a writer to handle gzip compression if requested.  It
+// returns the decorated writer and the appropriate "Content-Encoding" header
+// (which is empty if no compression is enabled).
+func decorateWriter(request *http.Request, writer io.Writer) (io.Writer, string) {
+	header := request.Header.Get(acceptEncodingHeader)
+	parts := strings.Split(header, ",")
+	for _, part := range parts {
+		part := strings.TrimSpace(part)
+		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
+			return gzip.NewWriter(writer), "gzip"
+		}
+	}
+	return writer, ""
+}
+
+type metricSorter []*dto.Metric
+
+func (s metricSorter) Len() int {
+	return len(s)
+}
+
+func (s metricSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s metricSorter) Less(i, j int) bool {
+	if len(s[i].Label) != len(s[j].Label) {
+		// This should not happen. The metrics are
+		// inconsistent. However, we have to deal with the fact, as
+		// people might use custom collectors or metric family injection
+		// to create inconsistent metrics. So let's simply compare the
+		// number of labels in this case. That will still yield
+		// reproducible sorting.
+		return len(s[i].Label) < len(s[j].Label)
+	}
+	for n, lp := range s[i].Label {
+		vi := lp.GetValue()
+		vj := s[j].Label[n].GetValue()
+		if vi != vj {
+			return vi < vj
+		}
+	}
+	return true
+}

vendor/github.com/prometheus/client_golang/prometheus/summary.go

@@ -0,0 +1,540 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"hash/fnv"
+	"math"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/beorn7/perks/quantile"
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// quantileLabel is used for the label that defines the quantile in a
+// summary.
+const quantileLabel = "quantile"
+
+// A Summary captures individual observations from an event or sample stream and
+// summarizes them in a manner similar to traditional summary statistics: 1. sum
+// of observations, 2. observation count, 3. rank estimations.
+//
+// A typical use-case is the observation of request latencies. By default, a
+// Summary provides the median, the 90th and the 99th percentile of the latency
+// as rank estimations.
+//
+// Note that the rank estimations cannot be aggregated in a meaningful way with
+// the Prometheus query language (i.e. you cannot average or add them). If you
+// need aggregatable quantiles (e.g. you want the 99th percentile latency of all
+// queries served across all instances of a service), consider the Histogram
+// metric type. See the Prometheus documentation for more details.
+//
+// To create Summary instances, use NewSummary.
+type Summary interface {
+	Metric
+	Collector
+
+	// Observe adds a single observation to the summary.
+	Observe(float64)
+}
+
+var (
+	// DefObjectives are the default Summary quantile values.
+	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
+
+	errQuantileLabelNotAllowed = fmt.Errorf(
+		"%q is not allowed as label name in summaries", quantileLabel,
+	)
+)
+
+// Default values for SummaryOpts.
+const (
+	// DefMaxAge is the default duration for which observations stay
+	// relevant.
+	DefMaxAge time.Duration = 10 * time.Minute
+	// DefAgeBuckets is the default number of buckets used to calculate the
+	// age of observations.
+	DefAgeBuckets = 5
+	// DefBufCap is the standard buffer size for collecting Summary observations.
+	DefBufCap = 500
+)
+
+// SummaryOpts bundles the options for creating a Summary metric. It is
+// mandatory to set Name and Help to a non-empty string. All other fields are
+// optional and can safely be left at their zero value.
+type SummaryOpts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Summary (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the Summary must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this Summary. Mandatory!
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this
+	// Summary. Summaries with the same fully-qualified name must have the
+	// same label names in their ConstLabels.
+	//
+	// Note that in most cases, labels have a value that varies during the
+	// lifetime of a process. Those labels are usually managed with a
+	// SummaryVec. ConstLabels serve only special purposes. One is for the
+	// special case where the value of a label does not change during the
+	// lifetime of a process, e.g. if the revision of the running binary is
+	// put into a label. Another, more advanced purpose is if more than one
+	// Collector needs to collect Summaries with the same fully-qualified
+	// name. In that case, those Summaries must differ in the values of
+	// their ConstLabels. See the Collector examples.
+	//
+	// If the value of a label never changes (not even between binaries),
+	// that label most likely should not be a label at all (but part of the
+	// metric name).
+	ConstLabels Labels
+
+	// Objectives defines the quantile rank estimates with their respective
+	// absolute error. If Objectives[q] = e, then the value reported
+	// for q will be the φ-quantile value for some φ between q-e and q+e.
+	// The default value is DefObjectives.
+	Objectives map[float64]float64
+
+	// MaxAge defines the duration for which an observation stays relevant
+	// for the summary. Must be positive. The default value is DefMaxAge.
+	MaxAge time.Duration
+
+	// AgeBuckets is the number of buckets used to exclude observations that
+	// are older than MaxAge from the summary. A higher number has a
+	// resource penalty, so only increase it if the higher resolution is
+	// really required. For very high observation rates, you might want to
+	// reduce the number of age buckets. With only one age bucket, you will
+	// effectively see a complete reset of the summary each time MaxAge has
+	// passed. The default value is DefAgeBuckets.
+	AgeBuckets uint32
+
+	// BufCap defines the default sample stream buffer size.  The default
+	// value of DefBufCap should suffice for most uses. If there is a need
+	// to increase the value, a multiple of 500 is recommended (because that
+	// is the internal buffer size of the underlying package
+	// "github.com/bmizerany/perks/quantile").
+	BufCap uint32
+}
+
+// TODO: Great fuck-up with the sliding-window decay algorithm... The Merge
+// method of perk/quantile is actually not working as advertised - and it might
+// be unfixable, as the underlying algorithm is apparently not capable of
+// merging summaries in the first place. To avoid using Merge, we are currently
+// adding observations to _each_ age bucket, i.e. the effort to add a sample is
+// essentially multiplied by the number of age buckets. When rotating age
+// buckets, we empty the previous head stream. On scrape time, we simply take
+// the quantiles from the head stream (no merging required). Result: More effort
+// on observation time, less effort on scrape time, which is exactly the
+// opposite of what we try to accomplish, but at least the results are correct.
+//
+// The quite elegant previous contraption to merge the age buckets efficiently
+// on scrape time (see code up commit 6b9530d72ea715f0ba612c0120e6e09fbf1d49d0)
+// can't be used anymore.
+
+// NewSummary creates a new Summary based on the provided SummaryOpts.
+func NewSummary(opts SummaryOpts) Summary {
+	return newSummary(
+		NewDesc(
+			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+			opts.Help,
+			nil,
+			opts.ConstLabels,
+		),
+		opts,
+	)
+}
+
+func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
+	if len(desc.variableLabels) != len(labelValues) {
+		panic(errInconsistentCardinality)
+	}
+
+	for _, n := range desc.variableLabels {
+		if n == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+
+	if len(opts.Objectives) == 0 {
+		opts.Objectives = DefObjectives
+	}
+
+	if opts.MaxAge < 0 {
+		panic(fmt.Errorf("illegal max age MaxAge=%v", opts.MaxAge))
+	}
+	if opts.MaxAge == 0 {
+		opts.MaxAge = DefMaxAge
+	}
+
+	if opts.AgeBuckets == 0 {
+		opts.AgeBuckets = DefAgeBuckets
+	}
+
+	if opts.BufCap == 0 {
+		opts.BufCap = DefBufCap
+	}
+
+	s := &summary{
+		desc: desc,
+
+		objectives:       opts.Objectives,
+		sortedObjectives: make([]float64, 0, len(opts.Objectives)),
+
+		labelPairs: makeLabelPairs(desc, labelValues),
+
+		hotBuf:         make([]float64, 0, opts.BufCap),
+		coldBuf:        make([]float64, 0, opts.BufCap),
+		streamDuration: opts.MaxAge / time.Duration(opts.AgeBuckets),
+	}
+	s.headStreamExpTime = time.Now().Add(s.streamDuration)
+	s.hotBufExpTime = s.headStreamExpTime
+
+	for i := uint32(0); i < opts.AgeBuckets; i++ {
+		s.streams = append(s.streams, s.newStream())
+	}
+	s.headStream = s.streams[0]
+
+	for qu := range s.objectives {
+		s.sortedObjectives = append(s.sortedObjectives, qu)
+	}
+	sort.Float64s(s.sortedObjectives)
+
+	s.Init(s) // Init self-collection.
+	return s
+}
+
+type summary struct {
+	SelfCollector
+
+	bufMtx sync.Mutex // Protects hotBuf and hotBufExpTime.
+	mtx    sync.Mutex // Protects every other moving part.
+	// Lock bufMtx before mtx if both are needed.
+
+	desc *Desc
+
+	objectives       map[float64]float64
+	sortedObjectives []float64
+
+	labelPairs []*dto.LabelPair
+
+	sum float64
+	cnt uint64
+
+	hotBuf, coldBuf []float64
+
+	streams                          []*quantile.Stream
+	streamDuration                   time.Duration
+	headStream                       *quantile.Stream
+	headStreamIdx                    int
+	headStreamExpTime, hotBufExpTime time.Time
+}
+
+func (s *summary) Desc() *Desc {
+	return s.desc
+}
+
+func (s *summary) Observe(v float64) {
+	s.bufMtx.Lock()
+	defer s.bufMtx.Unlock()
+
+	now := time.Now()
+	if now.After(s.hotBufExpTime) {
+		s.asyncFlush(now)
+	}
+	s.hotBuf = append(s.hotBuf, v)
+	if len(s.hotBuf) == cap(s.hotBuf) {
+		s.asyncFlush(now)
+	}
+}
+
+func (s *summary) Write(out *dto.Metric) error {
+	sum := &dto.Summary{}
+	qs := make([]*dto.Quantile, 0, len(s.objectives))
+
+	s.bufMtx.Lock()
+	s.mtx.Lock()
+	// Swap bufs even if hotBuf is empty to set new hotBufExpTime.
+	s.swapBufs(time.Now())
+	s.bufMtx.Unlock()
+
+	s.flushColdBuf()
+	sum.SampleCount = proto.Uint64(s.cnt)
+	sum.SampleSum = proto.Float64(s.sum)
+
+	for _, rank := range s.sortedObjectives {
+		var q float64
+		if s.headStream.Count() == 0 {
+			q = math.NaN()
+		} else {
+			q = s.headStream.Query(rank)
+		}
+		qs = append(qs, &dto.Quantile{
+			Quantile: proto.Float64(rank),
+			Value:    proto.Float64(q),
+		})
+	}
+
+	s.mtx.Unlock()
+
+	if len(qs) > 0 {
+		sort.Sort(quantSort(qs))
+	}
+	sum.Quantile = qs
+
+	out.Summary = sum
+	out.Label = s.labelPairs
+	return nil
+}
+
+func (s *summary) newStream() *quantile.Stream {
+	return quantile.NewTargeted(s.objectives)
+}
+
+// asyncFlush needs bufMtx locked.
+func (s *summary) asyncFlush(now time.Time) {
+	s.mtx.Lock()
+	s.swapBufs(now)
+
+	// Unblock the original goroutine that was responsible for the mutation
+	// that triggered the compaction.  But hold onto the global non-buffer
+	// state mutex until the operation finishes.
+	go func() {
+		s.flushColdBuf()
+		s.mtx.Unlock()
+	}()
+}
+
+// rotateStreams needs mtx AND bufMtx locked.
+func (s *summary) maybeRotateStreams() {
+	for !s.hotBufExpTime.Equal(s.headStreamExpTime) {
+		s.headStream.Reset()
+		s.headStreamIdx++
+		if s.headStreamIdx >= len(s.streams) {
+			s.headStreamIdx = 0
+		}
+		s.headStream = s.streams[s.headStreamIdx]
+		s.headStreamExpTime = s.headStreamExpTime.Add(s.streamDuration)
+	}
+}
+
+// flushColdBuf needs mtx locked.
+func (s *summary) flushColdBuf() {
+	for _, v := range s.coldBuf {
+		for _, stream := range s.streams {
+			stream.Insert(v)
+		}
+		s.cnt++
+		s.sum += v
+	}
+	s.coldBuf = s.coldBuf[0:0]
+	s.maybeRotateStreams()
+}
+
+// swapBufs needs mtx AND bufMtx locked, coldBuf must be empty.
+func (s *summary) swapBufs(now time.Time) {
+	if len(s.coldBuf) != 0 {
+		panic("coldBuf is not empty")
+	}
+	s.hotBuf, s.coldBuf = s.coldBuf, s.hotBuf
+	// hotBuf is now empty and gets new expiration set.
+	for now.After(s.hotBufExpTime) {
+		s.hotBufExpTime = s.hotBufExpTime.Add(s.streamDuration)
+	}
+}
+
+type quantSort []*dto.Quantile
+
+func (s quantSort) Len() int {
+	return len(s)
+}
+
+func (s quantSort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s quantSort) Less(i, j int) bool {
+	return s[i].GetQuantile() < s[j].GetQuantile()
+}
+
+// SummaryVec is a Collector that bundles a set of Summaries that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. HTTP request latencies, partitioned by status code and method). Create
+// instances with NewSummaryVec.
+type SummaryVec struct {
+	MetricVec
+}
+
+// NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &SummaryVec{
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newSummary(desc, opts, lvs...)
+			},
+		},
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Summary and not a
+// Metric so that no type conversion is required.
+func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Summary, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Summary), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Summary and not a Metric so that no
+// type conversion is required.
+func (m *SummaryVec) GetMetricWith(labels Labels) (Summary, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Summary), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Observe(42.21)
+func (m *SummaryVec) WithLabelValues(lvs ...string) Summary {
+	return m.MetricVec.WithLabelValues(lvs...).(Summary)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
+func (m *SummaryVec) With(labels Labels) Summary {
+	return m.MetricVec.With(labels).(Summary)
+}
+
+type constSummary struct {
+	desc       *Desc
+	count      uint64
+	sum        float64
+	quantiles  map[float64]float64
+	labelPairs []*dto.LabelPair
+}
+
+func (s *constSummary) Desc() *Desc {
+	return s.desc
+}
+
+func (s *constSummary) Write(out *dto.Metric) error {
+	sum := &dto.Summary{}
+	qs := make([]*dto.Quantile, 0, len(s.quantiles))
+
+	sum.SampleCount = proto.Uint64(s.count)
+	sum.SampleSum = proto.Float64(s.sum)
+
+	for rank, q := range s.quantiles {
+		qs = append(qs, &dto.Quantile{
+			Quantile: proto.Float64(rank),
+			Value:    proto.Float64(q),
+		})
+	}
+
+	if len(qs) > 0 {
+		sort.Sort(quantSort(qs))
+	}
+	sum.Quantile = qs
+
+	out.Summary = sum
+	out.Label = s.labelPairs
+
+	return nil
+}
+
+// NewConstSummary returns a metric representing a Prometheus summary with fixed
+// values for the count, sum, and quantiles. As those parameters cannot be
+// changed, the returned value does not implement the Summary interface (but
+// only the Metric interface). Users of this package will not have much use for
+// it in regular operations. However, when implementing custom Collectors, it is
+// useful as a throw-away metric that is generated on the fly to send it to
+// Prometheus in the Collect method.
+//
+// quantiles maps ranks to quantile values. For example, a median latency of
+// 0.23s and a 99th percentile latency of 0.56s would be expressed as:
+//     map[float64]float64{0.5: 0.23, 0.99: 0.56}
+//
+// NewConstSummary returns an error if the length of labelValues is not
+// consistent with the variable labels in Desc.
+func NewConstSummary(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	quantiles map[float64]float64,
+	labelValues ...string,
+) (Metric, error) {
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
+	}
+	return &constSummary{
+		desc:       desc,
+		count:      count,
+		sum:        sum,
+		quantiles:  quantiles,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstSummary is a version of NewConstSummary that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstSummary(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	quantiles map[float64]float64,
+	labelValues ...string,
+) Metric {
+	m, err := NewConstSummary(desc, count, sum, quantiles, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}

vendor/github.com/prometheus/client_golang/prometheus/untyped.go

@@ -0,0 +1,145 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import "hash/fnv"
+
+// Untyped is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// An Untyped metric works the same as a Gauge. The only difference is that to
+// no type information is implied.
+//
+// To create Untyped instances, use NewUntyped.
+type Untyped interface {
+	Metric
+	Collector
+
+	// Set sets the Untyped metric to an arbitrary value.
+	Set(float64)
+	// Inc increments the Untyped metric by 1.
+	Inc()
+	// Dec decrements the Untyped metric by 1.
+	Dec()
+	// Add adds the given value to the Untyped metric. (The value can be
+	// negative, resulting in a decrease.)
+	Add(float64)
+	// Sub subtracts the given value from the Untyped metric. (The value can
+	// be negative, resulting in an increase.)
+	Sub(float64)
+}
+
+// UntypedOpts is an alias for Opts. See there for doc comments.
+type UntypedOpts Opts
+
+// NewUntyped creates a new Untyped metric from the provided UntypedOpts.
+func NewUntyped(opts UntypedOpts) Untyped {
+	return newValue(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), UntypedValue, 0)
+}
+
+// UntypedVec is a Collector that bundles a set of Untyped metrics that all
+// share the same Desc, but have different values for their variable
+// labels. This is used if you want to count the same thing partitioned by
+// various dimensions. Create instances with NewUntypedVec.
+type UntypedVec struct {
+	MetricVec
+}
+
+// NewUntypedVec creates a new UntypedVec based on the provided UntypedOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewUntypedVec(opts UntypedOpts, labelNames []string) *UntypedVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &UntypedVec{
+		MetricVec: MetricVec{
+			children: map[uint64]Metric{},
+			desc:     desc,
+			hash:     fnv.New64a(),
+			newMetric: func(lvs ...string) Metric {
+				return newValue(desc, UntypedValue, 0, lvs...)
+			},
+		},
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns an Untyped and not a
+// Metric so that no type conversion is required.
+func (m *UntypedVec) GetMetricWithLabelValues(lvs ...string) (Untyped, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Untyped), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns an Untyped and not a Metric so that no
+// type conversion is required.
+func (m *UntypedVec) GetMetricWith(labels Labels) (Untyped, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Untyped), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *UntypedVec) WithLabelValues(lvs ...string) Untyped {
+	return m.MetricVec.WithLabelValues(lvs...).(Untyped)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+func (m *UntypedVec) With(labels Labels) Untyped {
+	return m.MetricVec.With(labels).(Untyped)
+}
+
+// UntypedFunc is an Untyped whose value is determined at collect time by
+// calling a provided function.
+//
+// To create UntypedFunc instances, use NewUntypedFunc.
+type UntypedFunc interface {
+	Metric
+	Collector
+}
+
+// NewUntypedFunc creates a new UntypedFunc based on the provided
+// UntypedOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where an UntypedFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func NewUntypedFunc(opts UntypedOpts, function func() float64) UntypedFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), UntypedValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/value.go

@@ -0,0 +1,234 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"sort"
+	"sync/atomic"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// ValueType is an enumeration of metric types that represent a simple value.
+type ValueType int
+
+// Possible values for the ValueType enum.
+const (
+	_ ValueType = iota
+	CounterValue
+	GaugeValue
+	UntypedValue
+)
+
+var errInconsistentCardinality = errors.New("inconsistent label cardinality")
+
+// value is a generic metric for simple values. It implements Metric, Collector,
+// Counter, Gauge, and Untyped. Its effective type is determined by
+// ValueType. This is a low-level building block used by the library to back the
+// implementations of Counter, Gauge, and Untyped.
+type value struct {
+	// valBits containst the bits of the represented float64 value. It has
+	// to go first in the struct to guarantee alignment for atomic
+	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+
+	SelfCollector
+
+	desc       *Desc
+	valType    ValueType
+	labelPairs []*dto.LabelPair
+}
+
+// newValue returns a newly allocated value with the given Desc, ValueType,
+// sample value and label values. It panics if the number of label
+// values is different from the number of variable labels in Desc.
+func newValue(desc *Desc, valueType ValueType, val float64, labelValues ...string) *value {
+	if len(labelValues) != len(desc.variableLabels) {
+		panic(errInconsistentCardinality)
+	}
+	result := &value{
+		desc:       desc,
+		valType:    valueType,
+		valBits:    math.Float64bits(val),
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}
+	result.Init(result)
+	return result
+}
+
+func (v *value) Desc() *Desc {
+	return v.desc
+}
+
+func (v *value) Set(val float64) {
+	atomic.StoreUint64(&v.valBits, math.Float64bits(val))
+}
+
+func (v *value) Inc() {
+	v.Add(1)
+}
+
+func (v *value) Dec() {
+	v.Add(-1)
+}
+
+func (v *value) Add(val float64) {
+	for {
+		oldBits := atomic.LoadUint64(&v.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
+		if atomic.CompareAndSwapUint64(&v.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (v *value) Sub(val float64) {
+	v.Add(val * -1)
+}
+
+func (v *value) Write(out *dto.Metric) error {
+	val := math.Float64frombits(atomic.LoadUint64(&v.valBits))
+	return populateMetric(v.valType, val, v.labelPairs, out)
+}
+
+// valueFunc is a generic metric for simple values retrieved on collect time
+// from a function. It implements Metric and Collector. Its effective type is
+// determined by ValueType. This is a low-level building block used by the
+// library to back the implementations of CounterFunc, GaugeFunc, and
+// UntypedFunc.
+type valueFunc struct {
+	SelfCollector
+
+	desc       *Desc
+	valType    ValueType
+	function   func() float64
+	labelPairs []*dto.LabelPair
+}
+
+// newValueFunc returns a newly allocated valueFunc with the given Desc and
+// ValueType. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a valueFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *valueFunc {
+	result := &valueFunc{
+		desc:       desc,
+		valType:    valueType,
+		function:   function,
+		labelPairs: makeLabelPairs(desc, nil),
+	}
+	result.Init(result)
+	return result
+}
+
+func (v *valueFunc) Desc() *Desc {
+	return v.desc
+}
+
+func (v *valueFunc) Write(out *dto.Metric) error {
+	return populateMetric(v.valType, v.function(), v.labelPairs, out)
+}
+
+// NewConstMetric returns a metric with one fixed value that cannot be
+// changed. Users of this package will not have much use for it in regular
+// operations. However, when implementing custom Collectors, it is useful as a
+// throw-away metric that is generated on the fly to send it to Prometheus in
+// the Collect method. NewConstMetric returns an error if the length of
+// labelValues is not consistent with the variable labels in Desc.
+func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
+	}
+	return &constMetric{
+		desc:       desc,
+		valType:    valueType,
+		val:        value,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstMetric is a version of NewConstMetric that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) Metric {
+	m, err := NewConstMetric(desc, valueType, value, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
+
+type constMetric struct {
+	desc       *Desc
+	valType    ValueType
+	val        float64
+	labelPairs []*dto.LabelPair
+}
+
+func (m *constMetric) Desc() *Desc {
+	return m.desc
+}
+
+func (m *constMetric) Write(out *dto.Metric) error {
+	return populateMetric(m.valType, m.val, m.labelPairs, out)
+}
+
+func populateMetric(
+	t ValueType,
+	v float64,
+	labelPairs []*dto.LabelPair,
+	m *dto.Metric,
+) error {
+	m.Label = labelPairs
+	switch t {
+	case CounterValue:
+		m.Counter = &dto.Counter{Value: proto.Float64(v)}
+	case GaugeValue:
+		m.Gauge = &dto.Gauge{Value: proto.Float64(v)}
+	case UntypedValue:
+		m.Untyped = &dto.Untyped{Value: proto.Float64(v)}
+	default:
+		return fmt.Errorf("encountered unknown type %v", t)
+	}
+	return nil
+}
+
+func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
+	totalLen := len(desc.variableLabels) + len(desc.constLabelPairs)
+	if totalLen == 0 {
+		// Super fast path.
+		return nil
+	}
+	if len(desc.variableLabels) == 0 {
+		// Moderately fast path.
+		return desc.constLabelPairs
+	}
+	labelPairs := make([]*dto.LabelPair, 0, totalLen)
+	for i, n := range desc.variableLabels {
+		labelPairs = append(labelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(labelValues[i]),
+		})
+	}
+	for _, lp := range desc.constLabelPairs {
+		labelPairs = append(labelPairs, lp)
+	}
+	sort.Sort(LabelPairSorter(labelPairs))
+	return labelPairs
+}

vendor/github.com/prometheus/client_golang/prometheus/vec.go

@@ -0,0 +1,247 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"bytes"
+	"fmt"
+	"hash"
+	"sync"
+)
+
+// MetricVec is a Collector to bundle metrics of the same name that
+// differ in their label values. MetricVec is usually not used directly but as a
+// building block for implementations of vectors of a given metric
+// type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already
+// provided in this package.
+type MetricVec struct {
+	mtx      sync.RWMutex // Protects not only children, but also hash and buf.
+	children map[uint64]Metric
+	desc     *Desc
+
+	// hash is our own hash instance to avoid repeated allocations.
+	hash hash.Hash64
+	// buf is used to copy string contents into it for hashing,
+	// again to avoid allocations.
+	buf bytes.Buffer
+
+	newMetric func(labelValues ...string) Metric
+}
+
+// Describe implements Collector. The length of the returned slice
+// is always one.
+func (m *MetricVec) Describe(ch chan<- *Desc) {
+	ch <- m.desc
+}
+
+// Collect implements Collector.
+func (m *MetricVec) Collect(ch chan<- Metric) {
+	m.mtx.RLock()
+	defer m.mtx.RUnlock()
+
+	for _, metric := range m.children {
+		ch <- metric
+	}
+}
+
+// GetMetricWithLabelValues returns the Metric for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Metric is created.
+//
+// It is possible to call this method without using the returned Metric to only
+// create the new Metric but leave it at its start value (e.g. a Summary or
+// Histogram without any observations). See also the SummaryVec example.
+//
+// Keeping the Metric for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Metric from the MetricVec. In that case, the
+// Metric will still exist, but it will not be exported anymore, even if a
+// Metric with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return nil, err
+	}
+	return m.getOrCreateMetric(h, lvs...), nil
+}
+
+// GetMetricWith returns the Metric for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Metric is created. Implications of
+// creating a Metric without using it and keeping the Metric for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc.
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return nil, err
+	}
+	lvs := make([]string, len(labels))
+	for i, label := range m.desc.variableLabels {
+		lvs[i] = labels[label]
+	}
+	return m.getOrCreateMetric(h, lvs...), nil
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics if an error
+// occurs. The method allows neat syntax like:
+//     httpReqs.WithLabelValues("404", "POST").Inc()
+func (m *MetricVec) WithLabelValues(lvs ...string) Metric {
+	metric, err := m.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return metric
+}
+
+// With works as GetMetricWith, but panics if an error occurs. The method allows
+// neat syntax like:
+//     httpReqs.With(Labels{"status":"404", "method":"POST"}).Inc()
+func (m *MetricVec) With(labels Labels) Metric {
+	metric, err := m.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return metric
+}
+
+// DeleteLabelValues removes the metric where the variable labels are the same
+// as those passed in as labels (same order as the VariableLabels in Desc). It
+// returns true if a metric was deleted.
+//
+// It is not an error if the number of label values is not the same as the
+// number of VariableLabels in Desc.  However, such inconsistent label count can
+// never match an actual Metric, so the method will always return false in that
+// case.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider Delete(Labels) as an
+// alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the CounterVec example.
+func (m *MetricVec) DeleteLabelValues(lvs ...string) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return false
+	}
+	if _, has := m.children[h]; !has {
+		return false
+	}
+	delete(m.children, h)
+	return true
+}
+
+// Delete deletes the metric where the variable labels are the same as those
+// passed in as labels. It returns true if a metric was deleted.
+//
+// It is not an error if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in the Desc of the MetricVec. However, such
+// inconsistent Labels can never match an actual Metric, so the method will
+// always return false in that case.
+//
+// This method is used for the same purpose as DeleteLabelValues(...string). See
+// there for pros and cons of the two methods.
+func (m *MetricVec) Delete(labels Labels) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return false
+	}
+	if _, has := m.children[h]; !has {
+		return false
+	}
+	delete(m.children, h)
+	return true
+}
+
+// Reset deletes all metrics in this vector.
+func (m *MetricVec) Reset() {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	for h := range m.children {
+		delete(m.children, h)
+	}
+}
+
+func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) {
+	if len(vals) != len(m.desc.variableLabels) {
+		return 0, errInconsistentCardinality
+	}
+	m.hash.Reset()
+	for _, val := range vals {
+		m.buf.Reset()
+		m.buf.WriteString(val)
+		m.hash.Write(m.buf.Bytes())
+	}
+	return m.hash.Sum64(), nil
+}
+
+func (m *MetricVec) hashLabels(labels Labels) (uint64, error) {
+	if len(labels) != len(m.desc.variableLabels) {
+		return 0, errInconsistentCardinality
+	}
+	m.hash.Reset()
+	for _, label := range m.desc.variableLabels {
+		val, ok := labels[label]
+		if !ok {
+			return 0, fmt.Errorf("label name %q missing in label map", label)
+		}
+		m.buf.Reset()
+		m.buf.WriteString(val)
+		m.hash.Write(m.buf.Bytes())
+	}
+	return m.hash.Sum64(), nil
+}
+
+func (m *MetricVec) getOrCreateMetric(hash uint64, labelValues ...string) Metric {
+	metric, ok := m.children[hash]
+	if !ok {
+		// Copy labelValues. Otherwise, they would be allocated even if we don't go
+		// down this code path.
+		copiedLabelValues := append(make([]string, 0, len(labelValues)), labelValues...)
+		metric = m.newMetric(copiedLabelValues...)
+		m.children[hash] = metric
+	}
+	return metric
+}

vendor/github.com/prometheus/client_model/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
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+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
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+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
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+      file or class name and description of purpose be included on the
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+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/client_model/NOTICE

@@ -0,0 +1,5 @@
+Data model artifacts for Prometheus.
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).

vendor/github.com/prometheus/client_model/go/metrics.pb.go

@@ -0,0 +1,364 @@
+// Code generated by protoc-gen-go.
+// source: metrics.proto
+// DO NOT EDIT!
+
+/*
+Package io_prometheus_client is a generated protocol buffer package.
+
+It is generated from these files:
+	metrics.proto
+
+It has these top-level messages:
+	LabelPair
+	Gauge
+	Counter
+	Quantile
+	Summary
+	Untyped
+	Histogram
+	Bucket
+	Metric
+	MetricFamily
+*/
+package io_prometheus_client
+
+import proto "github.com/golang/protobuf/proto"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = math.Inf
+
+type MetricType int32
+
+const (
+	MetricType_COUNTER   MetricType = 0
+	MetricType_GAUGE     MetricType = 1
+	MetricType_SUMMARY   MetricType = 2
+	MetricType_UNTYPED   MetricType = 3
+	MetricType_HISTOGRAM MetricType = 4
+)
+
+var MetricType_name = map[int32]string{
+	0: "COUNTER",
+	1: "GAUGE",
+	2: "SUMMARY",
+	3: "UNTYPED",
+	4: "HISTOGRAM",
+}
+var MetricType_value = map[string]int32{
+	"COUNTER":   0,
+	"GAUGE":     1,
+	"SUMMARY":   2,
+	"UNTYPED":   3,
+	"HISTOGRAM": 4,
+}
+
+func (x MetricType) Enum() *MetricType {
+	p := new(MetricType)
+	*p = x
+	return p
+}
+func (x MetricType) String() string {
+	return proto.EnumName(MetricType_name, int32(x))
+}
+func (x *MetricType) UnmarshalJSON(data []byte) error {
+	value, err := proto.UnmarshalJSONEnum(MetricType_value, data, "MetricType")
+	if err != nil {
+		return err
+	}
+	*x = MetricType(value)
+	return nil
+}
+
+type LabelPair struct {
+	Name             *string `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Value            *string `protobuf:"bytes,2,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte  `json:"-"`
+}
+
+func (m *LabelPair) Reset()         { *m = LabelPair{} }
+func (m *LabelPair) String() string { return proto.CompactTextString(m) }
+func (*LabelPair) ProtoMessage()    {}
+
+func (m *LabelPair) GetName() string {
+	if m != nil && m.Name != nil {
+		return *m.Name
+	}
+	return ""
+}
+
+func (m *LabelPair) GetValue() string {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return ""
+}
+
+type Gauge struct {
+	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Gauge) Reset()         { *m = Gauge{} }
+func (m *Gauge) String() string { return proto.CompactTextString(m) }
+func (*Gauge) ProtoMessage()    {}
+
+func (m *Gauge) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Counter struct {
+	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Counter) Reset()         { *m = Counter{} }
+func (m *Counter) String() string { return proto.CompactTextString(m) }
+func (*Counter) ProtoMessage()    {}
+
+func (m *Counter) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Quantile struct {
+	Quantile         *float64 `protobuf:"fixed64,1,opt,name=quantile" json:"quantile,omitempty"`
+	Value            *float64 `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Quantile) Reset()         { *m = Quantile{} }
+func (m *Quantile) String() string { return proto.CompactTextString(m) }
+func (*Quantile) ProtoMessage()    {}
+
+func (m *Quantile) GetQuantile() float64 {
+	if m != nil && m.Quantile != nil {
+		return *m.Quantile
+	}
+	return 0
+}
+
+func (m *Quantile) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Summary struct {
+	SampleCount      *uint64     `protobuf:"varint,1,opt,name=sample_count" json:"sample_count,omitempty"`
+	SampleSum        *float64    `protobuf:"fixed64,2,opt,name=sample_sum" json:"sample_sum,omitempty"`
+	Quantile         []*Quantile `protobuf:"bytes,3,rep,name=quantile" json:"quantile,omitempty"`
+	XXX_unrecognized []byte      `json:"-"`
+}
+
+func (m *Summary) Reset()         { *m = Summary{} }
+func (m *Summary) String() string { return proto.CompactTextString(m) }
+func (*Summary) ProtoMessage()    {}
+
+func (m *Summary) GetSampleCount() uint64 {
+	if m != nil && m.SampleCount != nil {
+		return *m.SampleCount
+	}
+	return 0
+}
+
+func (m *Summary) GetSampleSum() float64 {
+	if m != nil && m.SampleSum != nil {
+		return *m.SampleSum
+	}
+	return 0
+}
+
+func (m *Summary) GetQuantile() []*Quantile {
+	if m != nil {
+		return m.Quantile
+	}
+	return nil
+}
+
+type Untyped struct {
+	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Untyped) Reset()         { *m = Untyped{} }
+func (m *Untyped) String() string { return proto.CompactTextString(m) }
+func (*Untyped) ProtoMessage()    {}
+
+func (m *Untyped) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Histogram struct {
+	SampleCount      *uint64   `protobuf:"varint,1,opt,name=sample_count" json:"sample_count,omitempty"`
+	SampleSum        *float64  `protobuf:"fixed64,2,opt,name=sample_sum" json:"sample_sum,omitempty"`
+	Bucket           []*Bucket `protobuf:"bytes,3,rep,name=bucket" json:"bucket,omitempty"`
+	XXX_unrecognized []byte    `json:"-"`
+}
+
+func (m *Histogram) Reset()         { *m = Histogram{} }
+func (m *Histogram) String() string { return proto.CompactTextString(m) }
+func (*Histogram) ProtoMessage()    {}
+
+func (m *Histogram) GetSampleCount() uint64 {
+	if m != nil && m.SampleCount != nil {
+		return *m.SampleCount
+	}
+	return 0
+}
+
+func (m *Histogram) GetSampleSum() float64 {
+	if m != nil && m.SampleSum != nil {
+		return *m.SampleSum
+	}
+	return 0
+}
+
+func (m *Histogram) GetBucket() []*Bucket {
+	if m != nil {
+		return m.Bucket
+	}
+	return nil
+}
+
+type Bucket struct {
+	CumulativeCount  *uint64  `protobuf:"varint,1,opt,name=cumulative_count" json:"cumulative_count,omitempty"`
+	UpperBound       *float64 `protobuf:"fixed64,2,opt,name=upper_bound" json:"upper_bound,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Bucket) Reset()         { *m = Bucket{} }
+func (m *Bucket) String() string { return proto.CompactTextString(m) }
+func (*Bucket) ProtoMessage()    {}
+
+func (m *Bucket) GetCumulativeCount() uint64 {
+	if m != nil && m.CumulativeCount != nil {
+		return *m.CumulativeCount
+	}
+	return 0
+}
+
+func (m *Bucket) GetUpperBound() float64 {
+	if m != nil && m.UpperBound != nil {
+		return *m.UpperBound
+	}
+	return 0
+}
+
+type Metric struct {
+	Label            []*LabelPair `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
+	Gauge            *Gauge       `protobuf:"bytes,2,opt,name=gauge" json:"gauge,omitempty"`
+	Counter          *Counter     `protobuf:"bytes,3,opt,name=counter" json:"counter,omitempty"`
+	Summary          *Summary     `protobuf:"bytes,4,opt,name=summary" json:"summary,omitempty"`
+	Untyped          *Untyped     `protobuf:"bytes,5,opt,name=untyped" json:"untyped,omitempty"`
+	Histogram        *Histogram   `protobuf:"bytes,7,opt,name=histogram" json:"histogram,omitempty"`
+	TimestampMs      *int64       `protobuf:"varint,6,opt,name=timestamp_ms" json:"timestamp_ms,omitempty"`
+	XXX_unrecognized []byte       `json:"-"`
+}
+
+func (m *Metric) Reset()         { *m = Metric{} }
+func (m *Metric) String() string { return proto.CompactTextString(m) }
+func (*Metric) ProtoMessage()    {}
+
+func (m *Metric) GetLabel() []*LabelPair {
+	if m != nil {
+		return m.Label
+	}
+	return nil
+}
+
+func (m *Metric) GetGauge() *Gauge {
+	if m != nil {
+		return m.Gauge
+	}
+	return nil
+}
+
+func (m *Metric) GetCounter() *Counter {
+	if m != nil {
+		return m.Counter
+	}
+	return nil
+}
+
+func (m *Metric) GetSummary() *Summary {
+	if m != nil {
+		return m.Summary
+	}
+	return nil
+}
+
+func (m *Metric) GetUntyped() *Untyped {
+	if m != nil {
+		return m.Untyped
+	}
+	return nil
+}
+
+func (m *Metric) GetHistogram() *Histogram {
+	if m != nil {
+		return m.Histogram
+	}
+	return nil
+}
+
+func (m *Metric) GetTimestampMs() int64 {
+	if m != nil && m.TimestampMs != nil {
+		return *m.TimestampMs
+	}
+	return 0
+}
+
+type MetricFamily struct {
+	Name             *string     `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Help             *string     `protobuf:"bytes,2,opt,name=help" json:"help,omitempty"`
+	Type             *MetricType `protobuf:"varint,3,opt,name=type,enum=io.prometheus.client.MetricType" json:"type,omitempty"`
+	Metric           []*Metric   `protobuf:"bytes,4,rep,name=metric" json:"metric,omitempty"`
+	XXX_unrecognized []byte      `json:"-"`
+}
+
+func (m *MetricFamily) Reset()         { *m = MetricFamily{} }
+func (m *MetricFamily) String() string { return proto.CompactTextString(m) }
+func (*MetricFamily) ProtoMessage()    {}
+
+func (m *MetricFamily) GetName() string {
+	if m != nil && m.Name != nil {
+		return *m.Name
+	}
+	return ""
+}
+
+func (m *MetricFamily) GetHelp() string {
+	if m != nil && m.Help != nil {
+		return *m.Help
+	}
+	return ""
+}
+
+func (m *MetricFamily) GetType() MetricType {
+	if m != nil && m.Type != nil {
+		return *m.Type
+	}
+	return MetricType_COUNTER
+}
+
+func (m *MetricFamily) GetMetric() []*Metric {
+	if m != nil {
+		return m.Metric
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterEnum("io.prometheus.client.MetricType", MetricType_name, MetricType_value)
+}

vendor/github.com/prometheus/common/expfmt/decode.go

@@ -0,0 +1,411 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"math"
+	"mime"
+	"net/http"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+	"github.com/prometheus/common/model"
+)
+
+// Decoder types decode an input stream into metric families.
+type Decoder interface {
+	Decode(*dto.MetricFamily) error
+}
+
+type DecodeOptions struct {
+	// Timestamp is added to each value from the stream that has no explicit timestamp set.
+	Timestamp model.Time
+}
+
+// ResponseFormat extracts the correct format from a HTTP response header.
+// If no matching format can be found FormatUnknown is returned.
+func ResponseFormat(h http.Header) Format {
+	ct := h.Get(hdrContentType)
+
+	mediatype, params, err := mime.ParseMediaType(ct)
+	if err != nil {
+		return FmtUnknown
+	}
+
+	const (
+		textType = "text/plain"
+		jsonType = "application/json"
+	)
+
+	switch mediatype {
+	case ProtoType:
+		if p, ok := params["proto"]; ok && p != ProtoProtocol {
+			return FmtUnknown
+		}
+		if e, ok := params["encoding"]; ok && e != "delimited" {
+			return FmtUnknown
+		}
+		return FmtProtoDelim
+
+	case textType:
+		if v, ok := params["version"]; ok && v != TextVersion {
+			return FmtUnknown
+		}
+		return FmtText
+
+	case jsonType:
+		var prometheusAPIVersion string
+
+		if params["schema"] == "prometheus/telemetry" && params["version"] != "" {
+			prometheusAPIVersion = params["version"]
+		} else {
+			prometheusAPIVersion = h.Get("X-Prometheus-API-Version")
+		}
+
+		switch prometheusAPIVersion {
+		case "0.0.2", "":
+			return fmtJSON2
+		default:
+			return FmtUnknown
+		}
+	}
+
+	return FmtUnknown
+}
+
+// NewDecoder returns a new decoder based on the given input format.
+// If the input format does not imply otherwise, a text format decoder is returned.
+func NewDecoder(r io.Reader, format Format) Decoder {
+	switch format {
+	case FmtProtoDelim:
+		return &protoDecoder{r: r}
+	case fmtJSON2:
+		return newJSON2Decoder(r)
+	}
+	return &textDecoder{r: r}
+}
+
+// protoDecoder implements the Decoder interface for protocol buffers.
+type protoDecoder struct {
+	r io.Reader
+}
+
+// Decode implements the Decoder interface.
+func (d *protoDecoder) Decode(v *dto.MetricFamily) error {
+	_, err := pbutil.ReadDelimited(d.r, v)
+	return err
+}
+
+// textDecoder implements the Decoder interface for the text protcol.
+type textDecoder struct {
+	r    io.Reader
+	p    TextParser
+	fams []*dto.MetricFamily
+}
+
+// Decode implements the Decoder interface.
+func (d *textDecoder) Decode(v *dto.MetricFamily) error {
+	// TODO(fabxc): Wrap this as a line reader to make streaming safer.
+	if len(d.fams) == 0 {
+		// No cached metric families, read everything and parse metrics.
+		fams, err := d.p.TextToMetricFamilies(d.r)
+		if err != nil {
+			return err
+		}
+		if len(fams) == 0 {
+			return io.EOF
+		}
+		d.fams = make([]*dto.MetricFamily, 0, len(fams))
+		for _, f := range fams {
+			d.fams = append(d.fams, f)
+		}
+	}
+
+	*v = *d.fams[0]
+	d.fams = d.fams[1:]
+
+	return nil
+}
+
+type SampleDecoder struct {
+	Dec  Decoder
+	Opts *DecodeOptions
+
+	f dto.MetricFamily
+}
+
+func (sd *SampleDecoder) Decode(s *model.Vector) error {
+	if err := sd.Dec.Decode(&sd.f); err != nil {
+		return err
+	}
+	*s = extractSamples(&sd.f, sd.Opts)
+	return nil
+}
+
+// Extract samples builds a slice of samples from the provided metric families.
+func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) model.Vector {
+	var all model.Vector
+	for _, f := range fams {
+		all = append(all, extractSamples(f, o)...)
+	}
+	return all
+}
+
+func extractSamples(f *dto.MetricFamily, o *DecodeOptions) model.Vector {
+	switch f.GetType() {
+	case dto.MetricType_COUNTER:
+		return extractCounter(o, f)
+	case dto.MetricType_GAUGE:
+		return extractGauge(o, f)
+	case dto.MetricType_SUMMARY:
+		return extractSummary(o, f)
+	case dto.MetricType_UNTYPED:
+		return extractUntyped(o, f)
+	case dto.MetricType_HISTOGRAM:
+		return extractHistogram(o, f)
+	}
+	panic("expfmt.extractSamples: unknown metric family type")
+}
+
+func extractCounter(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Counter == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Counter.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractGauge(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Gauge == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Gauge.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractUntyped(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Untyped == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Untyped.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractSummary(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Summary == nil {
+			continue
+		}
+
+		timestamp := o.Timestamp
+		if m.TimestampMs != nil {
+			timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		}
+
+		for _, q := range m.Summary.Quantile {
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			// BUG(matt): Update other names to "quantile".
+			lset[model.LabelName(model.QuantileLabel)] = model.LabelValue(fmt.Sprint(q.GetQuantile()))
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     model.SampleValue(q.GetValue()),
+				Timestamp: timestamp,
+			})
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Summary.GetSampleSum()),
+			Timestamp: timestamp,
+		})
+
+		lset = make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Summary.GetSampleCount()),
+			Timestamp: timestamp,
+		})
+	}
+
+	return samples
+}
+
+func extractHistogram(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Histogram == nil {
+			continue
+		}
+
+		timestamp := o.Timestamp
+		if m.TimestampMs != nil {
+			timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		}
+
+		infSeen := false
+
+		for _, q := range m.Histogram.Bucket {
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			lset[model.LabelName(model.BucketLabel)] = model.LabelValue(fmt.Sprint(q.GetUpperBound()))
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+
+			if math.IsInf(q.GetUpperBound(), +1) {
+				infSeen = true
+			}
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     model.SampleValue(q.GetCumulativeCount()),
+				Timestamp: timestamp,
+			})
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Histogram.GetSampleSum()),
+			Timestamp: timestamp,
+		})
+
+		lset = make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
+
+		count := &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Histogram.GetSampleCount()),
+			Timestamp: timestamp,
+		}
+		samples = append(samples, count)
+
+		if !infSeen {
+			// Append an infinity bucket sample.
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			lset[model.LabelName(model.BucketLabel)] = model.LabelValue("+Inf")
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     count.Value,
+				Timestamp: timestamp,
+			})
+		}
+	}
+
+	return samples
+}

vendor/github.com/prometheus/common/expfmt/encode.go

@@ -0,0 +1,88 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+
+	"bitbucket.org/ww/goautoneg"
+	"github.com/golang/protobuf/proto"
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Encoder types encode metric families into an underlying wire protocol.
+type Encoder interface {
+	Encode(*dto.MetricFamily) error
+}
+
+type encoder func(*dto.MetricFamily) error
+
+func (e encoder) Encode(v *dto.MetricFamily) error {
+	return e(v)
+}
+
+// Negotiate returns the Content-Type based on the given Accept header.
+// If no appropriate accepted type is found, FmtText is returned.
+func Negotiate(h http.Header) Format {
+	for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
+		// Check for protocol buffer
+		if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
+			switch ac.Params["encoding"] {
+			case "delimited":
+				return FmtProtoDelim
+			case "text":
+				return FmtProtoText
+			case "compact-text":
+				return FmtProtoCompact
+			}
+		}
+		// Check for text format.
+		ver := ac.Params["version"]
+		if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
+			return FmtText
+		}
+	}
+	return FmtText
+}
+
+// NewEncoder returns a new encoder based on content type negotiation.
+func NewEncoder(w io.Writer, format Format) Encoder {
+	switch format {
+	case FmtProtoDelim:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := pbutil.WriteDelimited(w, v)
+			return err
+		})
+	case FmtProtoCompact:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := fmt.Fprintln(w, v.String())
+			return err
+		})
+	case FmtProtoText:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := fmt.Fprintln(w, proto.MarshalTextString(v))
+			return err
+		})
+	case FmtText:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := MetricFamilyToText(w, v)
+			return err
+		})
+	}
+	panic("expfmt.NewEncoder: unknown format")
+}

vendor/github.com/prometheus/common/expfmt/expfmt.go

@@ -0,0 +1,40 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// A package for reading and writing Prometheus metrics.
+package expfmt
+
+type Format string
+
+const (
+	TextVersion = "0.0.4"
+
+	ProtoType     = `application/vnd.google.protobuf`
+	ProtoProtocol = `io.prometheus.client.MetricFamily`
+	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"
+
+	// The Content-Type values for the different wire protocols.
+	FmtUnknown      Format = `<unknown>`
+	FmtText         Format = `text/plain; version=` + TextVersion
+	FmtProtoDelim   Format = ProtoFmt + ` encoding=delimited`
+	FmtProtoText    Format = ProtoFmt + ` encoding=text`
+	FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text`
+
+	// fmtJSON2 is hidden as it is deprecated.
+	fmtJSON2 Format = `application/json; version=0.0.2`
+)
+
+const (
+	hdrContentType = "Content-Type"
+	hdrAccept      = "Accept"
+)

vendor/github.com/prometheus/common/expfmt/fuzz.go

@@ -0,0 +1,36 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Build only when actually fuzzing
+// +build gofuzz
+
+package expfmt
+
+import "bytes"
+
+// Fuzz text metric parser with with github.com/dvyukov/go-fuzz:
+//
+//     go-fuzz-build github.com/prometheus/client_golang/text
+//     go-fuzz -bin text-fuzz.zip -workdir fuzz
+//
+// Further input samples should go in the folder fuzz/corpus.
+func Fuzz(in []byte) int {
+	parser := TextParser{}
+	_, err := parser.TextToMetricFamilies(bytes.NewReader(in))
+
+	if err != nil {
+		return 0
+	}
+
+	return 1
+}

vendor/github.com/prometheus/common/expfmt/json_decode.go

@@ -0,0 +1,162 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"sort"
+
+	"github.com/golang/protobuf/proto"
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/common/model"
+)
+
+type json2Decoder struct {
+	dec  *json.Decoder
+	fams []*dto.MetricFamily
+}
+
+func newJSON2Decoder(r io.Reader) Decoder {
+	return &json2Decoder{
+		dec: json.NewDecoder(r),
+	}
+}
+
+type histogram002 struct {
+	Labels model.LabelSet     `json:"labels"`
+	Values map[string]float64 `json:"value"`
+}
+
+type counter002 struct {
+	Labels model.LabelSet `json:"labels"`
+	Value  float64        `json:"value"`
+}
+
+func protoLabelSet(base, ext model.LabelSet) []*dto.LabelPair {
+	labels := base.Clone().Merge(ext)
+	delete(labels, model.MetricNameLabel)
+
+	names := make([]string, 0, len(labels))
+	for ln := range labels {
+		names = append(names, string(ln))
+	}
+	sort.Strings(names)
+
+	pairs := make([]*dto.LabelPair, 0, len(labels))
+
+	for _, ln := range names {
+		lv := labels[model.LabelName(ln)]
+
+		pairs = append(pairs, &dto.LabelPair{
+			Name:  proto.String(ln),
+			Value: proto.String(string(lv)),
+		})
+	}
+
+	return pairs
+}
+
+func (d *json2Decoder) more() error {
+	var entities []struct {
+		BaseLabels model.LabelSet `json:"baseLabels"`
+		Docstring  string         `json:"docstring"`
+		Metric     struct {
+			Type   string          `json:"type"`
+			Values json.RawMessage `json:"value"`
+		} `json:"metric"`
+	}
+
+	if err := d.dec.Decode(&entities); err != nil {
+		return err
+	}
+	for _, e := range entities {
+		f := &dto.MetricFamily{
+			Name:   proto.String(string(e.BaseLabels[model.MetricNameLabel])),
+			Help:   proto.String(e.Docstring),
+			Type:   dto.MetricType_UNTYPED.Enum(),
+			Metric: []*dto.Metric{},
+		}
+
+		d.fams = append(d.fams, f)
+
+		switch e.Metric.Type {
+		case "counter", "gauge":
+			var values []counter002
+
+			if err := json.Unmarshal(e.Metric.Values, &values); err != nil {
+				return fmt.Errorf("could not extract %s value: %s", e.Metric.Type, err)
+			}
+
+			for _, ctr := range values {
+				f.Metric = append(f.Metric, &dto.Metric{
+					Label: protoLabelSet(e.BaseLabels, ctr.Labels),
+					Untyped: &dto.Untyped{
+						Value: proto.Float64(ctr.Value),
+					},
+				})
+			}
+
+		case "histogram":
+			var values []histogram002
+
+			if err := json.Unmarshal(e.Metric.Values, &values); err != nil {
+				return fmt.Errorf("could not extract %s value: %s", e.Metric.Type, err)
+			}
+
+			for _, hist := range values {
+				quants := make([]string, 0, len(values))
+				for q := range hist.Values {
+					quants = append(quants, q)
+				}
+
+				sort.Strings(quants)
+
+				for _, q := range quants {
+					value := hist.Values[q]
+					// The correct label is "quantile" but to not break old expressions
+					// this remains "percentile"
+					hist.Labels["percentile"] = model.LabelValue(q)
+
+					f.Metric = append(f.Metric, &dto.Metric{
+						Label: protoLabelSet(e.BaseLabels, hist.Labels),
+						Untyped: &dto.Untyped{
+							Value: proto.Float64(value),
+						},
+					})
+				}
+			}
+
+		default:
+			return fmt.Errorf("unknown metric type %q", e.Metric.Type)
+		}
+	}
+	return nil
+}
+
+// Decode implements the Decoder interface.
+func (d *json2Decoder) Decode(v *dto.MetricFamily) error {
+	if len(d.fams) == 0 {
+		if err := d.more(); err != nil {
+			return err
+		}
+	}
+
+	*v = *d.fams[0]
+	d.fams = d.fams[1:]
+
+	return nil
+}

vendor/github.com/prometheus/common/expfmt/text_create.go

@@ -0,0 +1,305 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/model"
+)
+
+// MetricFamilyToText converts a MetricFamily proto message into text format and
+// writes the resulting lines to 'out'. It returns the number of bytes written
+// and any error encountered.  This function does not perform checks on the
+// content of the metric and label names, i.e. invalid metric or label names
+// will result in invalid text format output.
+// This method fulfills the type 'prometheus.encoder'.
+func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (int, error) {
+	var written int
+
+	// Fail-fast checks.
+	if len(in.Metric) == 0 {
+		return written, fmt.Errorf("MetricFamily has no metrics: %s", in)
+	}
+	name := in.GetName()
+	if name == "" {
+		return written, fmt.Errorf("MetricFamily has no name: %s", in)
+	}
+
+	// Comments, first HELP, then TYPE.
+	if in.Help != nil {
+		n, err := fmt.Fprintf(
+			out, "# HELP %s %s\n",
+			name, escapeString(*in.Help, false),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	metricType := in.GetType()
+	n, err := fmt.Fprintf(
+		out, "# TYPE %s %s\n",
+		name, strings.ToLower(metricType.String()),
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+
+	// Finally the samples, one line for each.
+	for _, metric := range in.Metric {
+		switch metricType {
+		case dto.MetricType_COUNTER:
+			if metric.Counter == nil {
+				return written, fmt.Errorf(
+					"expected counter in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Counter.GetValue(),
+				out,
+			)
+		case dto.MetricType_GAUGE:
+			if metric.Gauge == nil {
+				return written, fmt.Errorf(
+					"expected gauge in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Gauge.GetValue(),
+				out,
+			)
+		case dto.MetricType_UNTYPED:
+			if metric.Untyped == nil {
+				return written, fmt.Errorf(
+					"expected untyped in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Untyped.GetValue(),
+				out,
+			)
+		case dto.MetricType_SUMMARY:
+			if metric.Summary == nil {
+				return written, fmt.Errorf(
+					"expected summary in metric %s %s", name, metric,
+				)
+			}
+			for _, q := range metric.Summary.Quantile {
+				n, err = writeSample(
+					name, metric,
+					model.QuantileLabel, fmt.Sprint(q.GetQuantile()),
+					q.GetValue(),
+					out,
+				)
+				written += n
+				if err != nil {
+					return written, err
+				}
+			}
+			n, err = writeSample(
+				name+"_sum", metric, "", "",
+				metric.Summary.GetSampleSum(),
+				out,
+			)
+			if err != nil {
+				return written, err
+			}
+			written += n
+			n, err = writeSample(
+				name+"_count", metric, "", "",
+				float64(metric.Summary.GetSampleCount()),
+				out,
+			)
+		case dto.MetricType_HISTOGRAM:
+			if metric.Histogram == nil {
+				return written, fmt.Errorf(
+					"expected histogram in metric %s %s", name, metric,
+				)
+			}
+			infSeen := false
+			for _, q := range metric.Histogram.Bucket {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					model.BucketLabel, fmt.Sprint(q.GetUpperBound()),
+					float64(q.GetCumulativeCount()),
+					out,
+				)
+				written += n
+				if err != nil {
+					return written, err
+				}
+				if math.IsInf(q.GetUpperBound(), +1) {
+					infSeen = true
+				}
+			}
+			if !infSeen {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					model.BucketLabel, "+Inf",
+					float64(metric.Histogram.GetSampleCount()),
+					out,
+				)
+				if err != nil {
+					return written, err
+				}
+				written += n
+			}
+			n, err = writeSample(
+				name+"_sum", metric, "", "",
+				metric.Histogram.GetSampleSum(),
+				out,
+			)
+			if err != nil {
+				return written, err
+			}
+			written += n
+			n, err = writeSample(
+				name+"_count", metric, "", "",
+				float64(metric.Histogram.GetSampleCount()),
+				out,
+			)
+		default:
+			return written, fmt.Errorf(
+				"unexpected type in metric %s %s", name, metric,
+			)
+		}
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	return written, nil
+}
+
+// writeSample writes a single sample in text format to out, given the metric
+// name, the metric proto message itself, optionally an additional label name
+// and value (use empty strings if not required), and the value. The function
+// returns the number of bytes written and any error encountered.
+func writeSample(
+	name string,
+	metric *dto.Metric,
+	additionalLabelName, additionalLabelValue string,
+	value float64,
+	out io.Writer,
+) (int, error) {
+	var written int
+	n, err := fmt.Fprint(out, name)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = labelPairsToText(
+		metric.Label,
+		additionalLabelName, additionalLabelValue,
+		out,
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = fmt.Fprintf(out, " %v", value)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if metric.TimestampMs != nil {
+		n, err = fmt.Fprintf(out, " %v", *metric.TimestampMs)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err = out.Write([]byte{'\n'})
+	written += n
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// labelPairsToText converts a slice of LabelPair proto messages plus the
+// explicitly given additional label pair into text formatted as required by the
+// text format and writes it to 'out'. An empty slice in combination with an
+// empty string 'additionalLabelName' results in nothing being
+// written. Otherwise, the label pairs are written, escaped as required by the
+// text format, and enclosed in '{...}'. The function returns the number of
+// bytes written and any error encountered.
+func labelPairsToText(
+	in []*dto.LabelPair,
+	additionalLabelName, additionalLabelValue string,
+	out io.Writer,
+) (int, error) {
+	if len(in) == 0 && additionalLabelName == "" {
+		return 0, nil
+	}
+	var written int
+	separator := '{'
+	for _, lp := range in {
+		n, err := fmt.Fprintf(
+			out, `%c%s="%s"`,
+			separator, lp.GetName(), escapeString(lp.GetValue(), true),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		separator = ','
+	}
+	if additionalLabelName != "" {
+		n, err := fmt.Fprintf(
+			out, `%c%s="%s"`,
+			separator, additionalLabelName,
+			escapeString(additionalLabelValue, true),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err := out.Write([]byte{'}'})
+	written += n
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// escapeString replaces '\' by '\\', new line character by '\n', and - if
+// includeDoubleQuote is true - '"' by '\"'.
+func escapeString(v string, includeDoubleQuote bool) string {
+	result := bytes.NewBuffer(make([]byte, 0, len(v)))
+	for _, c := range v {
+		switch {
+		case c == '\\':
+			result.WriteString(`\\`)
+		case includeDoubleQuote && c == '"':
+			result.WriteString(`\"`)
+		case c == '\n':
+			result.WriteString(`\n`)
+		default:
+			result.WriteRune(c)
+		}
+	}
+	return result.String()
+}

vendor/github.com/prometheus/common/expfmt/text_parse.go

@@ -0,0 +1,746 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/model"
+)
+
+// A stateFn is a function that represents a state in a state machine. By
+// executing it, the state is progressed to the next state. The stateFn returns
+// another stateFn, which represents the new state. The end state is represented
+// by nil.
+type stateFn func() stateFn
+
+// ParseError signals errors while parsing the simple and flat text-based
+// exchange format.
+type ParseError struct {
+	Line int
+	Msg  string
+}
+
+// Error implements the error interface.
+func (e ParseError) Error() string {
+	return fmt.Sprintf("text format parsing error in line %d: %s", e.Line, e.Msg)
+}
+
+// TextParser is used to parse the simple and flat text-based exchange format. Its
+// nil value is ready to use.
+type TextParser struct {
+	metricFamiliesByName map[string]*dto.MetricFamily
+	buf                  *bufio.Reader // Where the parsed input is read through.
+	err                  error         // Most recent error.
+	lineCount            int           // Tracks the line count for error messages.
+	currentByte          byte          // The most recent byte read.
+	currentToken         bytes.Buffer  // Re-used each time a token has to be gathered from multiple bytes.
+	currentMF            *dto.MetricFamily
+	currentMetric        *dto.Metric
+	currentLabelPair     *dto.LabelPair
+
+	// The remaining member variables are only used for summaries/histograms.
+	currentLabels map[string]string // All labels including '__name__' but excluding 'quantile'/'le'
+	// Summary specific.
+	summaries       map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentQuantile float64
+	// Histogram specific.
+	histograms    map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentBucket float64
+	// These tell us if the currently processed line ends on '_count' or
+	// '_sum' respectively and belong to a summary/histogram, representing the sample
+	// count and sum of that summary/histogram.
+	currentIsSummaryCount, currentIsSummarySum     bool
+	currentIsHistogramCount, currentIsHistogramSum bool
+}
+
+// TextToMetricFamilies reads 'in' as the simple and flat text-based exchange
+// format and creates MetricFamily proto messages. It returns the MetricFamily
+// proto messages in a map where the metric names are the keys, along with any
+// error encountered.
+//
+// If the input contains duplicate metrics (i.e. lines with the same metric name
+// and exactly the same label set), the resulting MetricFamily will contain
+// duplicate Metric proto messages. Similar is true for duplicate label
+// names. Checks for duplicates have to be performed separately, if required.
+// Also note that neither the metrics within each MetricFamily are sorted nor
+// the label pairs within each Metric. Sorting is not required for the most
+// frequent use of this method, which is sample ingestion in the Prometheus
+// server. However, for presentation purposes, you might want to sort the
+// metrics, and in some cases, you must sort the labels, e.g. for consumption by
+// the metric family injection hook of the Prometheus registry.
+//
+// Summaries and histograms are rather special beasts. You would probably not
+// use them in the simple text format anyway. This method can deal with
+// summaries and histograms if they are presented in exactly the way the
+// text.Create function creates them.
+//
+// This method must not be called concurrently. If you want to parse different
+// input concurrently, instantiate a separate Parser for each goroutine.
+func (p *TextParser) TextToMetricFamilies(in io.Reader) (map[string]*dto.MetricFamily, error) {
+	p.reset(in)
+	for nextState := p.startOfLine; nextState != nil; nextState = nextState() {
+		// Magic happens here...
+	}
+	// Get rid of empty metric families.
+	for k, mf := range p.metricFamiliesByName {
+		if len(mf.GetMetric()) == 0 {
+			delete(p.metricFamiliesByName, k)
+		}
+	}
+	return p.metricFamiliesByName, p.err
+}
+
+func (p *TextParser) reset(in io.Reader) {
+	p.metricFamiliesByName = map[string]*dto.MetricFamily{}
+	if p.buf == nil {
+		p.buf = bufio.NewReader(in)
+	} else {
+		p.buf.Reset(in)
+	}
+	p.err = nil
+	p.lineCount = 0
+	if p.summaries == nil || len(p.summaries) > 0 {
+		p.summaries = map[uint64]*dto.Metric{}
+	}
+	if p.histograms == nil || len(p.histograms) > 0 {
+		p.histograms = map[uint64]*dto.Metric{}
+	}
+	p.currentQuantile = math.NaN()
+	p.currentBucket = math.NaN()
+}
+
+// startOfLine represents the state where the next byte read from p.buf is the
+// start of a line (or whitespace leading up to it).
+func (p *TextParser) startOfLine() stateFn {
+	p.lineCount++
+	if p.skipBlankTab(); p.err != nil {
+		// End of input reached. This is the only case where
+		// that is not an error but a signal that we are done.
+		p.err = nil
+		return nil
+	}
+	switch p.currentByte {
+	case '#':
+		return p.startComment
+	case '\n':
+		return p.startOfLine // Empty line, start the next one.
+	}
+	return p.readingMetricName
+}
+
+// startComment represents the state where the next byte read from p.buf is the
+// start of a comment (or whitespace leading up to it).
+func (p *TextParser) startComment() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	// If we have hit the end of line already, there is nothing left
+	// to do. This is not considered a syntax error.
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	keyword := p.currentToken.String()
+	if keyword != "HELP" && keyword != "TYPE" {
+		// Generic comment, ignore by fast forwarding to end of line.
+		for p.currentByte != '\n' {
+			if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+				return nil // Unexpected end of input.
+			}
+		}
+		return p.startOfLine
+	}
+	// There is something. Next has to be a metric name.
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	if !isBlankOrTab(p.currentByte) {
+		p.parseError("invalid metric name in comment")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	switch keyword {
+	case "HELP":
+		return p.readingHelp
+	case "TYPE":
+		return p.readingType
+	}
+	panic(fmt.Sprintf("code error: unexpected keyword %q", keyword))
+}
+
+// readingMetricName represents the state where the last byte read (now in
+// p.currentByte) is the first byte of a metric name.
+func (p *TextParser) readingMetricName() stateFn {
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError("invalid metric name")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	// Now is the time to fix the type if it hasn't happened yet.
+	if p.currentMF.Type == nil {
+		p.currentMF.Type = dto.MetricType_UNTYPED.Enum()
+	}
+	p.currentMetric = &dto.Metric{}
+	// Do not append the newly created currentMetric to
+	// currentMF.Metric right now. First wait if this is a summary,
+	// and the metric exists already, which we can only know after
+	// having read all the labels.
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	return p.readingLabels
+}
+
+// readingLabels represents the state where the last byte read (now in
+// p.currentByte) is either the first byte of the label set (i.e. a '{'), or the
+// first byte of the value (otherwise).
+func (p *TextParser) readingLabels() stateFn {
+	// Summaries/histograms are special. We have to reset the
+	// currentLabels map, currentQuantile and currentBucket before starting to
+	// read labels.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY || p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		p.currentLabels = map[string]string{}
+		p.currentLabels[string(model.MetricNameLabel)] = p.currentMF.GetName()
+		p.currentQuantile = math.NaN()
+		p.currentBucket = math.NaN()
+	}
+	if p.currentByte != '{' {
+		return p.readingValue
+	}
+	return p.startLabelName
+}
+
+// startLabelName represents the state where the next byte read from p.buf is
+// the start of a label name (or whitespace leading up to it).
+func (p *TextParser) startLabelName() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '}' {
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	}
+	if p.readTokenAsLabelName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError(fmt.Sprintf("invalid label name for metric %q", p.currentMF.GetName()))
+		return nil
+	}
+	p.currentLabelPair = &dto.LabelPair{Name: proto.String(p.currentToken.String())}
+	if p.currentLabelPair.GetName() == string(model.MetricNameLabel) {
+		p.parseError(fmt.Sprintf("label name %q is reserved", model.MetricNameLabel))
+		return nil
+	}
+	// Special summary/histogram treatment. Don't add 'quantile' and 'le'
+	// labels to 'real' labels.
+	if !(p.currentMF.GetType() == dto.MetricType_SUMMARY && p.currentLabelPair.GetName() == model.QuantileLabel) &&
+		!(p.currentMF.GetType() == dto.MetricType_HISTOGRAM && p.currentLabelPair.GetName() == model.BucketLabel) {
+		p.currentMetric.Label = append(p.currentMetric.Label, p.currentLabelPair)
+	}
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '=' {
+		p.parseError(fmt.Sprintf("expected '=' after label name, found %q", p.currentByte))
+		return nil
+	}
+	return p.startLabelValue
+}
+
+// startLabelValue represents the state where the next byte read from p.buf is
+// the start of a (quoted) label value (or whitespace leading up to it).
+func (p *TextParser) startLabelValue() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '"' {
+		p.parseError(fmt.Sprintf("expected '\"' at start of label value, found %q", p.currentByte))
+		return nil
+	}
+	if p.readTokenAsLabelValue(); p.err != nil {
+		return nil
+	}
+	p.currentLabelPair.Value = proto.String(p.currentToken.String())
+	// Special treatment of summaries:
+	// - Quantile labels are special, will result in dto.Quantile later.
+	// - Other labels have to be added to currentLabels for signature calculation.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		if p.currentLabelPair.GetName() == model.QuantileLabel {
+			if p.currentQuantile, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'quantile' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	// Similar special treatment of histograms.
+	if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		if p.currentLabelPair.GetName() == model.BucketLabel {
+			if p.currentBucket, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'le' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	switch p.currentByte {
+	case ',':
+		return p.startLabelName
+
+	case '}':
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	default:
+		p.parseError(fmt.Sprintf("unexpected end of label value %q", p.currentLabelPair.Value))
+		return nil
+	}
+}
+
+// readingValue represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the sample value (i.e. a float).
+func (p *TextParser) readingValue() stateFn {
+	// When we are here, we have read all the labels, so for the
+	// special case of a summary/histogram, we can finally find out
+	// if the metric already exists.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if summary := p.summaries[signature]; summary != nil {
+			p.currentMetric = summary
+		} else {
+			p.summaries[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if histogram := p.histograms[signature]; histogram != nil {
+			p.currentMetric = histogram
+		} else {
+			p.histograms[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else {
+		p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	value, err := strconv.ParseFloat(p.currentToken.String(), 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected float as value, got %q", p.currentToken.String()))
+		return nil
+	}
+	switch p.currentMF.GetType() {
+	case dto.MetricType_COUNTER:
+		p.currentMetric.Counter = &dto.Counter{Value: proto.Float64(value)}
+	case dto.MetricType_GAUGE:
+		p.currentMetric.Gauge = &dto.Gauge{Value: proto.Float64(value)}
+	case dto.MetricType_UNTYPED:
+		p.currentMetric.Untyped = &dto.Untyped{Value: proto.Float64(value)}
+	case dto.MetricType_SUMMARY:
+		// *sigh*
+		if p.currentMetric.Summary == nil {
+			p.currentMetric.Summary = &dto.Summary{}
+		}
+		switch {
+		case p.currentIsSummaryCount:
+			p.currentMetric.Summary.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsSummarySum:
+			p.currentMetric.Summary.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentQuantile):
+			p.currentMetric.Summary.Quantile = append(
+				p.currentMetric.Summary.Quantile,
+				&dto.Quantile{
+					Quantile: proto.Float64(p.currentQuantile),
+					Value:    proto.Float64(value),
+				},
+			)
+		}
+	case dto.MetricType_HISTOGRAM:
+		// *sigh*
+		if p.currentMetric.Histogram == nil {
+			p.currentMetric.Histogram = &dto.Histogram{}
+		}
+		switch {
+		case p.currentIsHistogramCount:
+			p.currentMetric.Histogram.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsHistogramSum:
+			p.currentMetric.Histogram.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentBucket):
+			p.currentMetric.Histogram.Bucket = append(
+				p.currentMetric.Histogram.Bucket,
+				&dto.Bucket{
+					UpperBound:      proto.Float64(p.currentBucket),
+					CumulativeCount: proto.Uint64(uint64(value)),
+				},
+			)
+		}
+	default:
+		p.err = fmt.Errorf("unexpected type for metric name %q", p.currentMF.GetName())
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	return p.startTimestamp
+}
+
+// startTimestamp represents the state where the next byte read from p.buf is
+// the start of the timestamp (or whitespace leading up to it).
+func (p *TextParser) startTimestamp() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	timestamp, err := strconv.ParseInt(p.currentToken.String(), 10, 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected integer as timestamp, got %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMetric.TimestampMs = proto.Int64(timestamp)
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() > 0 {
+		p.parseError(fmt.Sprintf("spurious string after timestamp: %q", p.currentToken.String()))
+		return nil
+	}
+	return p.startOfLine
+}
+
+// readingHelp represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the docstring after 'HELP'.
+func (p *TextParser) readingHelp() stateFn {
+	if p.currentMF.Help != nil {
+		p.parseError(fmt.Sprintf("second HELP line for metric name %q", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the docstring.
+	if p.readTokenUntilNewline(true); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	p.currentMF.Help = proto.String(p.currentToken.String())
+	return p.startOfLine
+}
+
+// readingType represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the type hint after 'HELP'.
+func (p *TextParser) readingType() stateFn {
+	if p.currentMF.Type != nil {
+		p.parseError(fmt.Sprintf("second TYPE line for metric name %q, or TYPE reported after samples", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the type.
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	metricType, ok := dto.MetricType_value[strings.ToUpper(p.currentToken.String())]
+	if !ok {
+		p.parseError(fmt.Sprintf("unknown metric type %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMF.Type = dto.MetricType(metricType).Enum()
+	return p.startOfLine
+}
+
+// parseError sets p.err to a ParseError at the current line with the given
+// message.
+func (p *TextParser) parseError(msg string) {
+	p.err = ParseError{
+		Line: p.lineCount,
+		Msg:  msg,
+	}
+}
+
+// skipBlankTab reads (and discards) bytes from p.buf until it encounters a byte
+// that is neither ' ' nor '\t'. That byte is left in p.currentByte.
+func (p *TextParser) skipBlankTab() {
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil || !isBlankOrTab(p.currentByte) {
+			return
+		}
+	}
+}
+
+// skipBlankTabIfCurrentBlankTab works exactly as skipBlankTab but doesn't do
+// anything if p.currentByte is neither ' ' nor '\t'.
+func (p *TextParser) skipBlankTabIfCurrentBlankTab() {
+	if isBlankOrTab(p.currentByte) {
+		p.skipBlankTab()
+	}
+}
+
+// readTokenUntilWhitespace copies bytes from p.buf into p.currentToken.  The
+// first byte considered is the byte already read (now in p.currentByte).  The
+// first whitespace byte encountered is still copied into p.currentByte, but not
+// into p.currentToken.
+func (p *TextParser) readTokenUntilWhitespace() {
+	p.currentToken.Reset()
+	for p.err == nil && !isBlankOrTab(p.currentByte) && p.currentByte != '\n' {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenUntilNewline copies bytes from p.buf into p.currentToken.  The first
+// byte considered is the byte already read (now in p.currentByte).  The first
+// newline byte encountered is still copied into p.currentByte, but not into
+// p.currentToken. If recognizeEscapeSequence is true, two escape sequences are
+// recognized: '\\' tranlates into '\', and '\n' into a line-feed character. All
+// other escape sequences are invalid and cause an error.
+func (p *TextParser) readTokenUntilNewline(recognizeEscapeSequence bool) {
+	p.currentToken.Reset()
+	escaped := false
+	for p.err == nil {
+		if recognizeEscapeSequence && escaped {
+			switch p.currentByte {
+			case '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+		} else {
+			switch p.currentByte {
+			case '\n':
+				return
+			case '\\':
+				escaped = true
+			default:
+				p.currentToken.WriteByte(p.currentByte)
+			}
+		}
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenAsMetricName copies a metric name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a metric name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *TextParser) readTokenAsMetricName() {
+	p.currentToken.Reset()
+	if !isValidMetricNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidMetricNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelName copies a label name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a label name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *TextParser) readTokenAsLabelName() {
+	p.currentToken.Reset()
+	if !isValidLabelNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidLabelNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelValue copies a label value from p.buf into p.currentToken.
+// In contrast to the other 'readTokenAs...' functions, which start with the
+// last read byte in p.currentByte, this method ignores p.currentByte and starts
+// with reading a new byte from p.buf. The first byte not part of a label value
+// is still copied into p.currentByte, but not into p.currentToken.
+func (p *TextParser) readTokenAsLabelValue() {
+	p.currentToken.Reset()
+	escaped := false
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+			return
+		}
+		if escaped {
+			switch p.currentByte {
+			case '"', '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+			continue
+		}
+		switch p.currentByte {
+		case '"':
+			return
+		case '\n':
+			p.parseError(fmt.Sprintf("label value %q contains unescaped new-line", p.currentToken.String()))
+			return
+		case '\\':
+			escaped = true
+		default:
+			p.currentToken.WriteByte(p.currentByte)
+		}
+	}
+}
+
+func (p *TextParser) setOrCreateCurrentMF() {
+	p.currentIsSummaryCount = false
+	p.currentIsSummarySum = false
+	p.currentIsHistogramCount = false
+	p.currentIsHistogramSum = false
+	name := p.currentToken.String()
+	if p.currentMF = p.metricFamiliesByName[name]; p.currentMF != nil {
+		return
+	}
+	// Try out if this is a _sum or _count for a summary/histogram.
+	summaryName := summaryMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[summaryName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+			if isCount(name) {
+				p.currentIsSummaryCount = true
+			}
+			if isSum(name) {
+				p.currentIsSummarySum = true
+			}
+			return
+		}
+	}
+	histogramName := histogramMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[histogramName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+			if isCount(name) {
+				p.currentIsHistogramCount = true
+			}
+			if isSum(name) {
+				p.currentIsHistogramSum = true
+			}
+			return
+		}
+	}
+	p.currentMF = &dto.MetricFamily{Name: proto.String(name)}
+	p.metricFamiliesByName[name] = p.currentMF
+}
+
+func isValidLabelNameStart(b byte) bool {
+	return (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_'
+}
+
+func isValidLabelNameContinuation(b byte) bool {
+	return isValidLabelNameStart(b) || (b >= '0' && b <= '9')
+}
+
+func isValidMetricNameStart(b byte) bool {
+	return isValidLabelNameStart(b) || b == ':'
+}
+
+func isValidMetricNameContinuation(b byte) bool {
+	return isValidLabelNameContinuation(b) || b == ':'
+}
+
+func isBlankOrTab(b byte) bool {
+	return b == ' ' || b == '\t'
+}
+
+func isCount(name string) bool {
+	return len(name) > 6 && name[len(name)-6:] == "_count"
+}
+
+func isSum(name string) bool {
+	return len(name) > 4 && name[len(name)-4:] == "_sum"
+}
+
+func isBucket(name string) bool {
+	return len(name) > 7 && name[len(name)-7:] == "_bucket"
+}
+
+func summaryMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	default:
+		return name
+	}
+}
+
+func histogramMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	case isBucket(name):
+		return name[:len(name)-7]
+	default:
+		return name
+	}
+}

vendor/github.com/prometheus/common/model/fingerprinting.go

@@ -0,0 +1,105 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// Fingerprint provides a hash-capable representation of a Metric.
+// For our purposes, FNV-1A 64-bit is used.
+type Fingerprint uint64
+
+// FingerprintFromString transforms a string representation into a Fingerprint.
+func FingerprintFromString(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	return Fingerprint(num), err
+}
+
+// ParseFingerprint parses the input string into a fingerprint.
+func ParseFingerprint(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	if err != nil {
+		return 0, err
+	}
+	return Fingerprint(num), nil
+}
+
+func (f Fingerprint) String() string {
+	return fmt.Sprintf("%016x", uint64(f))
+}
+
+// Fingerprints represents a collection of Fingerprint subject to a given
+// natural sorting scheme. It implements sort.Interface.
+type Fingerprints []Fingerprint
+
+// Len implements sort.Interface.
+func (f Fingerprints) Len() int {
+	return len(f)
+}
+
+// Less implements sort.Interface.
+func (f Fingerprints) Less(i, j int) bool {
+	return f[i] < f[j]
+}
+
+// Swap implements sort.Interface.
+func (f Fingerprints) Swap(i, j int) {
+	f[i], f[j] = f[j], f[i]
+}
+
+// FingerprintSet is a set of Fingerprints.
+type FingerprintSet map[Fingerprint]struct{}
+
+// Equal returns true if both sets contain the same elements (and not more).
+func (s FingerprintSet) Equal(o FingerprintSet) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for k := range s {
+		if _, ok := o[k]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Intersection returns the elements contained in both sets.
+func (s FingerprintSet) Intersection(o FingerprintSet) FingerprintSet {
+	myLength, otherLength := len(s), len(o)
+	if myLength == 0 || otherLength == 0 {
+		return FingerprintSet{}
+	}
+
+	subSet := s
+	superSet := o
+
+	if otherLength < myLength {
+		subSet = o
+		superSet = s
+	}
+
+	out := FingerprintSet{}
+
+	for k := range subSet {
+		if _, ok := superSet[k]; ok {
+			out[k] = struct{}{}
+		}
+	}
+
+	return out
+}

vendor/github.com/prometheus/common/model/labels.go

@@ -0,0 +1,188 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"sort"
+	"strings"
+)
+
+const (
+	// AlertNameLabel is the name of the label containing the an alert's name.
+	AlertNameLabel = "alertname"
+
+	// ExportedLabelPrefix is the prefix to prepend to the label names present in
+	// exported metrics if a label of the same name is added by the server.
+	ExportedLabelPrefix = "exported_"
+
+	// MetricNameLabel is the label name indicating the metric name of a
+	// timeseries.
+	MetricNameLabel = "__name__"
+
+	// SchemeLabel is the name of the label that holds the scheme on which to
+	// scrape a target.
+	SchemeLabel = "__scheme__"
+
+	// AddressLabel is the name of the label that holds the address of
+	// a scrape target.
+	AddressLabel = "__address__"
+
+	// MetricsPathLabel is the name of the label that holds the path on which to
+	// scrape a target.
+	MetricsPathLabel = "__metrics_path__"
+
+	// ReservedLabelPrefix is a prefix which is not legal in user-supplied
+	// label names.
+	ReservedLabelPrefix = "__"
+
+	// MetaLabelPrefix is a prefix for labels that provide meta information.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series.
+	MetaLabelPrefix = "__meta_"
+
+	// TmpLabelPrefix is a prefix for temporary labels as part of relabelling.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series. This is reserved for use in
+	// Prometheus configuration files by users.
+	TmpLabelPrefix = "__tmp_"
+
+	// ParamLabelPrefix is a prefix for labels that provide URL parameters
+	// used to scrape a target.
+	ParamLabelPrefix = "__param_"
+
+	// JobLabel is the label name indicating the job from which a timeseries
+	// was scraped.
+	JobLabel = "job"
+
+	// InstanceLabel is the label name used for the instance label.
+	InstanceLabel = "instance"
+
+	// BucketLabel is used for the label that defines the upper bound of a
+	// bucket of a histogram ("le" -> "less or equal").
+	BucketLabel = "le"
+
+	// QuantileLabel is used for the label that defines the quantile in a
+	// summary.
+	QuantileLabel = "quantile"
+)
+
+// LabelNameRE is a regular expression matching valid label names.
+var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+
+// A LabelName is a key for a LabelSet or Metric.  It has a value associated
+// therewith.
+type LabelName string
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (ln *LabelName) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	if !LabelNameRE.MatchString(s) {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (ln *LabelName) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	if !LabelNameRE.MatchString(s) {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// LabelNames is a sortable LabelName slice. In implements sort.Interface.
+type LabelNames []LabelName
+
+func (l LabelNames) Len() int {
+	return len(l)
+}
+
+func (l LabelNames) Less(i, j int) bool {
+	return l[i] < l[j]
+}
+
+func (l LabelNames) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+func (l LabelNames) String() string {
+	labelStrings := make([]string, 0, len(l))
+	for _, label := range l {
+		labelStrings = append(labelStrings, string(label))
+	}
+	return strings.Join(labelStrings, ", ")
+}
+
+// A LabelValue is an associated value for a LabelName.
+type LabelValue string
+
+// LabelValues is a sortable LabelValue slice. It implements sort.Interface.
+type LabelValues []LabelValue
+
+func (l LabelValues) Len() int {
+	return len(l)
+}
+
+func (l LabelValues) Less(i, j int) bool {
+	return sort.StringsAreSorted([]string{string(l[i]), string(l[j])})
+}
+
+func (l LabelValues) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+// LabelPair pairs a name with a value.
+type LabelPair struct {
+	Name  LabelName
+	Value LabelValue
+}
+
+// LabelPairs is a sortable slice of LabelPair pointers. It implements
+// sort.Interface.
+type LabelPairs []*LabelPair
+
+func (l LabelPairs) Len() int {
+	return len(l)
+}
+
+func (l LabelPairs) Less(i, j int) bool {
+	switch {
+	case l[i].Name > l[j].Name:
+		return false
+	case l[i].Name < l[j].Name:
+		return true
+	case l[i].Value > l[j].Value:
+		return false
+	case l[i].Value < l[j].Value:
+		return true
+	default:
+		return false
+	}
+}
+
+func (l LabelPairs) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}

vendor/github.com/prometheus/common/model/labelset.go

@@ -0,0 +1,153 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// A LabelSet is a collection of LabelName and LabelValue pairs.  The LabelSet
+// may be fully-qualified down to the point where it may resolve to a single
+// Metric in the data store or not.  All operations that occur within the realm
+// of a LabelSet can emit a vector of Metric entities to which the LabelSet may
+// match.
+type LabelSet map[LabelName]LabelValue
+
+func (ls LabelSet) Equal(o LabelSet) bool {
+	if len(ls) != len(o) {
+		return false
+	}
+	for ln, lv := range ls {
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if olv != lv {
+			return false
+		}
+	}
+	return true
+}
+
+// Before compares the metrics, using the following criteria:
+//
+// If m has fewer labels than o, it is before o. If it has more, it is not.
+//
+// If the number of labels is the same, the superset of all label names is
+// sorted alphanumerically. The first differing label pair found in that order
+// determines the outcome: If the label does not exist at all in m, then m is
+// before o, and vice versa. Otherwise the label value is compared
+// alphanumerically.
+//
+// If m and o are equal, the method returns false.
+func (ls LabelSet) Before(o LabelSet) bool {
+	if len(ls) < len(o) {
+		return true
+	}
+	if len(ls) > len(o) {
+		return false
+	}
+
+	lns := make(LabelNames, 0, len(ls)+len(o))
+	for ln := range ls {
+		lns = append(lns, ln)
+	}
+	for ln := range o {
+		lns = append(lns, ln)
+	}
+	// It's probably not worth it to de-dup lns.
+	sort.Sort(lns)
+	for _, ln := range lns {
+		mlv, ok := ls[ln]
+		if !ok {
+			return true
+		}
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if mlv < olv {
+			return true
+		}
+		if mlv > olv {
+			return false
+		}
+	}
+	return false
+}
+
+func (ls LabelSet) Clone() LabelSet {
+	lsn := make(LabelSet, len(ls))
+	for ln, lv := range ls {
+		lsn[ln] = lv
+	}
+	return lsn
+}
+
+// Merge is a helper function to non-destructively merge two label sets.
+func (l LabelSet) Merge(other LabelSet) LabelSet {
+	result := make(LabelSet, len(l))
+
+	for k, v := range l {
+		result[k] = v
+	}
+
+	for k, v := range other {
+		result[k] = v
+	}
+
+	return result
+}
+
+func (l LabelSet) String() string {
+	lstrs := make([]string, 0, len(l))
+	for l, v := range l {
+		lstrs = append(lstrs, fmt.Sprintf("%s=%q", l, v))
+	}
+
+	sort.Strings(lstrs)
+	return fmt.Sprintf("{%s}", strings.Join(lstrs, ", "))
+}
+
+// Fingerprint returns the LabelSet's fingerprint.
+func (ls LabelSet) Fingerprint() Fingerprint {
+	return labelSetToFingerprint(ls)
+}
+
+// FastFingerprint returns the LabelSet's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (ls LabelSet) FastFingerprint() Fingerprint {
+	return labelSetToFastFingerprint(ls)
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (l *LabelSet) UnmarshalJSON(b []byte) error {
+	var m map[LabelName]LabelValue
+	if err := json.Unmarshal(b, &m); err != nil {
+		return err
+	}
+	// encoding/json only unmarshals maps of the form map[string]T. It treats
+	// LabelName as a string and does not call its UnmarshalJSON method.
+	// Thus, we have to replicate the behavior here.
+	for ln := range m {
+		if !LabelNameRE.MatchString(string(ln)) {
+			return fmt.Errorf("%q is not a valid label name", ln)
+		}
+	}
+	*l = LabelSet(m)
+	return nil
+}

vendor/github.com/prometheus/common/model/metric.go

@@ -0,0 +1,81 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+var separator = []byte{0}
+
+// A Metric is similar to a LabelSet, but the key difference is that a Metric is
+// a singleton and refers to one and only one stream of samples.
+type Metric LabelSet
+
+// Equal compares the metrics.
+func (m Metric) Equal(o Metric) bool {
+	return LabelSet(m).Equal(LabelSet(o))
+}
+
+// Before compares the metrics' underlying label sets.
+func (m Metric) Before(o Metric) bool {
+	return LabelSet(m).Before(LabelSet(o))
+}
+
+// Clone returns a copy of the Metric.
+func (m Metric) Clone() Metric {
+	clone := Metric{}
+	for k, v := range m {
+		clone[k] = v
+	}
+	return clone
+}
+
+func (m Metric) String() string {
+	metricName, hasName := m[MetricNameLabel]
+	numLabels := len(m) - 1
+	if !hasName {
+		numLabels = len(m)
+	}
+	labelStrings := make([]string, 0, numLabels)
+	for label, value := range m {
+		if label != MetricNameLabel {
+			labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
+		}
+	}
+
+	switch numLabels {
+	case 0:
+		if hasName {
+			return string(metricName)
+		}
+		return "{}"
+	default:
+		sort.Strings(labelStrings)
+		return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", "))
+	}
+}
+
+// Fingerprint returns a Metric's Fingerprint.
+func (m Metric) Fingerprint() Fingerprint {
+	return LabelSet(m).Fingerprint()
+}
+
+// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (m Metric) FastFingerprint() Fingerprint {
+	return LabelSet(m).FastFingerprint()
+}

vendor/github.com/prometheus/common/model/model.go

@@ -0,0 +1,16 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package model contains common data structures that are shared across
+// Prometheus componenets and libraries.
+package model

vendor/github.com/prometheus/common/model/signature.go

@@ -0,0 +1,190 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"bytes"
+	"hash"
+	"hash/fnv"
+	"sort"
+	"sync"
+)
+
+// SeparatorByte is a byte that cannot occur in valid UTF-8 sequences and is
+// used to separate label names, label values, and other strings from each other
+// when calculating their combined hash value (aka signature aka fingerprint).
+const SeparatorByte byte = 255
+
+var (
+	// cache the signature of an empty label set.
+	emptyLabelSignature = fnv.New64a().Sum64()
+
+	hashAndBufPool sync.Pool
+)
+
+type hashAndBuf struct {
+	h hash.Hash64
+	b bytes.Buffer
+}
+
+func getHashAndBuf() *hashAndBuf {
+	hb := hashAndBufPool.Get()
+	if hb == nil {
+		return &hashAndBuf{h: fnv.New64a()}
+	}
+	return hb.(*hashAndBuf)
+}
+
+func putHashAndBuf(hb *hashAndBuf) {
+	hb.h.Reset()
+	hb.b.Reset()
+	hashAndBufPool.Put(hb)
+}
+
+// LabelsToSignature returns a quasi-unique signature (i.e., fingerprint) for a
+// given label set. (Collisions are possible but unlikely if the number of label
+// sets the function is applied to is small.)
+func LabelsToSignature(labels map[string]string) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make([]string, 0, len(labels))
+	for labelName := range labels {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Strings(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(labelName)
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(labels[labelName])
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}
+
+// labelSetToFingerprint works exactly as LabelsToSignature but takes a LabelSet as
+// parameter (rather than a label map) and returns a Fingerprint.
+func labelSetToFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	labelNames := make(LabelNames, 0, len(ls))
+	for labelName := range ls {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Sort(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(ls[labelName]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return Fingerprint(hb.h.Sum64())
+}
+
+// labelSetToFastFingerprint works similar to labelSetToFingerprint but uses a
+// faster and less allocation-heavy hash function, which is more susceptible to
+// create hash collisions. Therefore, collision detection should be applied.
+func labelSetToFastFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	var result uint64
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for labelName, labelValue := range ls {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(labelValue))
+		hb.h.Write(hb.b.Bytes())
+		result ^= hb.h.Sum64()
+		hb.h.Reset()
+		hb.b.Reset()
+	}
+	return Fingerprint(result)
+}
+
+// SignatureForLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and only includes the labels with the
+// specified LabelNames into the signature calculation. The labels passed in
+// will be sorted by this function.
+func SignatureForLabels(m Metric, labels ...LabelName) uint64 {
+	if len(m) == 0 || len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	sort.Sort(LabelNames(labels))
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, label := range labels {
+		hb.b.WriteString(string(label))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[label]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}
+
+// SignatureWithoutLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and excludes the labels with any of the
+// specified LabelNames from the signature calculation.
+func SignatureWithoutLabels(m Metric, labels map[LabelName]struct{}) uint64 {
+	if len(m) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make(LabelNames, 0, len(m))
+	for labelName := range m {
+		if _, exclude := labels[labelName]; !exclude {
+			labelNames = append(labelNames, labelName)
+		}
+	}
+	if len(labelNames) == 0 {
+		return emptyLabelSignature
+	}
+	sort.Sort(labelNames)
+
+	hb := getHashAndBuf()
+	defer putHashAndBuf(hb)
+
+	for _, labelName := range labelNames {
+		hb.b.WriteString(string(labelName))
+		hb.b.WriteByte(SeparatorByte)
+		hb.b.WriteString(string(m[labelName]))
+		hb.b.WriteByte(SeparatorByte)
+		hb.h.Write(hb.b.Bytes())
+		hb.b.Reset()
+	}
+	return hb.h.Sum64()
+}

vendor/github.com/prometheus/common/model/time.go

@@ -0,0 +1,230 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	// MinimumTick is the minimum supported time resolution. This has to be
+	// at least time.Second in order for the code below to work.
+	minimumTick = time.Millisecond
+	// second is the Time duration equivalent to one second.
+	second = int64(time.Second / minimumTick)
+	// The number of nanoseconds per minimum tick.
+	nanosPerTick = int64(minimumTick / time.Nanosecond)
+
+	// Earliest is the earliest Time representable. Handy for
+	// initializing a high watermark.
+	Earliest = Time(math.MinInt64)
+	// Latest is the latest Time representable. Handy for initializing
+	// a low watermark.
+	Latest = Time(math.MaxInt64)
+)
+
+// Time is the number of milliseconds since the epoch
+// (1970-01-01 00:00 UTC) excluding leap seconds.
+type Time int64
+
+// Interval describes and interval between two timestamps.
+type Interval struct {
+	Start, End Time
+}
+
+// Now returns the current time as a Time.
+func Now() Time {
+	return TimeFromUnixNano(time.Now().UnixNano())
+}
+
+// TimeFromUnix returns the Time equivalent to the Unix Time t
+// provided in seconds.
+func TimeFromUnix(t int64) Time {
+	return Time(t * second)
+}
+
+// TimeFromUnixNano returns the Time equivalent to the Unix Time
+// t provided in nanoseconds.
+func TimeFromUnixNano(t int64) Time {
+	return Time(t / nanosPerTick)
+}
+
+// Equal reports whether two Times represent the same instant.
+func (t Time) Equal(o Time) bool {
+	return t == o
+}
+
+// Before reports whether the Time t is before o.
+func (t Time) Before(o Time) bool {
+	return t < o
+}
+
+// After reports whether the Time t is after o.
+func (t Time) After(o Time) bool {
+	return t > o
+}
+
+// Add returns the Time t + d.
+func (t Time) Add(d time.Duration) Time {
+	return t + Time(d/minimumTick)
+}
+
+// Sub returns the Duration t - o.
+func (t Time) Sub(o Time) time.Duration {
+	return time.Duration(t-o) * minimumTick
+}
+
+// Time returns the time.Time representation of t.
+func (t Time) Time() time.Time {
+	return time.Unix(int64(t)/second, (int64(t)%second)*nanosPerTick)
+}
+
+// Unix returns t as a Unix time, the number of seconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) Unix() int64 {
+	return int64(t) / second
+}
+
+// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) UnixNano() int64 {
+	return int64(t) * nanosPerTick
+}
+
+// The number of digits after the dot.
+var dotPrecision = int(math.Log10(float64(second)))
+
+// String returns a string representation of the Time.
+func (t Time) String() string {
+	return strconv.FormatFloat(float64(t)/float64(second), 'f', -1, 64)
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (t Time) MarshalJSON() ([]byte, error) {
+	return []byte(t.String()), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (t *Time) UnmarshalJSON(b []byte) error {
+	p := strings.Split(string(b), ".")
+	switch len(p) {
+	case 1:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		*t = Time(v * second)
+
+	case 2:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		v *= second
+
+		prec := dotPrecision - len(p[1])
+		if prec < 0 {
+			p[1] = p[1][:dotPrecision]
+		} else if prec > 0 {
+			p[1] = p[1] + strings.Repeat("0", prec)
+		}
+
+		va, err := strconv.ParseInt(p[1], 10, 32)
+		if err != nil {
+			return err
+		}
+
+		*t = Time(v + va)
+
+	default:
+		return fmt.Errorf("invalid time %q", string(b))
+	}
+	return nil
+}
+
+// Duration wraps time.Duration. It is used to parse the custom duration format
+// from YAML.
+// This type should not propagate beyond the scope of input/output processing.
+type Duration time.Duration
+
+// StringToDuration parses a string into a time.Duration, assuming that a year
+// a day always has 24h.
+func ParseDuration(durationStr string) (Duration, error) {
+	matches := durationRE.FindStringSubmatch(durationStr)
+	if len(matches) != 3 {
+		return 0, fmt.Errorf("not a valid duration string: %q", durationStr)
+	}
+	durSeconds, _ := strconv.Atoi(matches[1])
+	dur := time.Duration(durSeconds) * time.Second
+	unit := matches[2]
+	switch unit {
+	case "d":
+		dur *= 60 * 60 * 24
+	case "h":
+		dur *= 60 * 60
+	case "m":
+		dur *= 60
+	case "s":
+		dur *= 1
+	default:
+		return 0, fmt.Errorf("invalid time unit in duration string: %q", unit)
+	}
+	return Duration(dur), nil
+}
+
+var durationRE = regexp.MustCompile("^([0-9]+)([ywdhms]+)$")
+
+func (d Duration) String() string {
+	seconds := int64(time.Duration(d) / time.Second)
+	factors := map[string]int64{
+		"d": 60 * 60 * 24,
+		"h": 60 * 60,
+		"m": 60,
+		"s": 1,
+	}
+	unit := "s"
+	switch int64(0) {
+	case seconds % factors["d"]:
+		unit = "d"
+	case seconds % factors["h"]:
+		unit = "h"
+	case seconds % factors["m"]:
+		unit = "m"
+	}
+	return fmt.Sprintf("%v%v", seconds/factors[unit], unit)
+}
+
+// MarshalYAML implements the yaml.Marshaler interface.
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return d.String(), nil
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (d *Duration) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	dur, err := ParseDuration(s)
+	if err != nil {
+		return err
+	}
+	*d = dur
+	return nil
+}

vendor/github.com/prometheus/common/model/value.go

@@ -0,0 +1,395 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// A SampleValue is a representation of a value for a given sample at a given
+// time.
+type SampleValue float64
+
+// MarshalJSON implements json.Marshaler.
+func (v SampleValue) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.String())
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (v *SampleValue) UnmarshalJSON(b []byte) error {
+	if len(b) < 2 || b[0] != '"' || b[len(b)-1] != '"' {
+		return fmt.Errorf("sample value must be a quoted string")
+	}
+	f, err := strconv.ParseFloat(string(b[1:len(b)-1]), 64)
+	if err != nil {
+		return err
+	}
+	*v = SampleValue(f)
+	return nil
+}
+
+func (v SampleValue) Equal(o SampleValue) bool {
+	return v == o
+}
+
+func (v SampleValue) String() string {
+	return strconv.FormatFloat(float64(v), 'f', -1, 64)
+}
+
+// SamplePair pairs a SampleValue with a Timestamp.
+type SamplePair struct {
+	Timestamp Time
+	Value     SampleValue
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s SamplePair) MarshalJSON() ([]byte, error) {
+	t, err := json.Marshal(s.Timestamp)
+	if err != nil {
+		return nil, err
+	}
+	v, err := json.Marshal(s.Value)
+	if err != nil {
+		return nil, err
+	}
+	return []byte(fmt.Sprintf("[%s,%s]", t, v)), nil
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *SamplePair) UnmarshalJSON(b []byte) error {
+	v := [...]json.Unmarshaler{&s.Timestamp, &s.Value}
+	return json.Unmarshal(b, &v)
+}
+
+// Equal returns true if this SamplePair and o have equal Values and equal
+// Timestamps.
+func (s *SamplePair) Equal(o *SamplePair) bool {
+	return s == o || (s.Value == o.Value && s.Timestamp.Equal(o.Timestamp))
+}
+
+func (s SamplePair) String() string {
+	return fmt.Sprintf("%s @[%s]", s.Value, s.Timestamp)
+}
+
+// Sample is a sample pair associated with a metric.
+type Sample struct {
+	Metric    Metric      `json:"metric"`
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+// Equal compares first the metrics, then the timestamp, then the value.
+func (s *Sample) Equal(o *Sample) bool {
+	if s == o {
+		return true
+	}
+
+	if !s.Metric.Equal(o.Metric) {
+		return false
+	}
+	if !s.Timestamp.Equal(o.Timestamp) {
+		return false
+	}
+	if s.Value != o.Value {
+		return false
+	}
+
+	return true
+}
+
+func (s Sample) String() string {
+	return fmt.Sprintf("%s => %s", s.Metric, SamplePair{
+		Timestamp: s.Timestamp,
+		Value:     s.Value,
+	})
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s Sample) MarshalJSON() ([]byte, error) {
+	v := struct {
+		Metric Metric     `json:"metric"`
+		Value  SamplePair `json:"value"`
+	}{
+		Metric: s.Metric,
+		Value: SamplePair{
+			Timestamp: s.Timestamp,
+			Value:     s.Value,
+		},
+	}
+
+	return json.Marshal(&v)
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *Sample) UnmarshalJSON(b []byte) error {
+	v := struct {
+		Metric Metric     `json:"metric"`
+		Value  SamplePair `json:"value"`
+	}{
+		Metric: s.Metric,
+		Value: SamplePair{
+			Timestamp: s.Timestamp,
+			Value:     s.Value,
+		},
+	}
+
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+
+	s.Metric = v.Metric
+	s.Timestamp = v.Value.Timestamp
+	s.Value = v.Value.Value
+
+	return nil
+}
+
+// Samples is a sortable Sample slice. It implements sort.Interface.
+type Samples []*Sample
+
+func (s Samples) Len() int {
+	return len(s)
+}
+
+// Less compares first the metrics, then the timestamp.
+func (s Samples) Less(i, j int) bool {
+	switch {
+	case s[i].Metric.Before(s[j].Metric):
+		return true
+	case s[j].Metric.Before(s[i].Metric):
+		return false
+	case s[i].Timestamp.Before(s[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+func (s Samples) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (s Samples) Equal(o Samples) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for i, sample := range s {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// SampleStream is a stream of Values belonging to an attached COWMetric.
+type SampleStream struct {
+	Metric Metric       `json:"metric"`
+	Values []SamplePair `json:"values"`
+}
+
+func (ss SampleStream) String() string {
+	vals := make([]string, len(ss.Values))
+	for i, v := range ss.Values {
+		vals[i] = v.String()
+	}
+	return fmt.Sprintf("%s =>\n%s", ss.Metric, strings.Join(vals, "\n"))
+}
+
+// Value is a generic interface for values resulting from a query evaluation.
+type Value interface {
+	Type() ValueType
+	String() string
+}
+
+func (Matrix) Type() ValueType  { return ValMatrix }
+func (Vector) Type() ValueType  { return ValVector }
+func (*Scalar) Type() ValueType { return ValScalar }
+func (*String) Type() ValueType { return ValString }
+
+type ValueType int
+
+const (
+	ValNone ValueType = iota
+	ValScalar
+	ValVector
+	ValMatrix
+	ValString
+)
+
+// MarshalJSON implements json.Marshaler.
+func (et ValueType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(et.String())
+}
+
+func (et *ValueType) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	switch s {
+	case "<ValNone>":
+		*et = ValNone
+	case "scalar":
+		*et = ValScalar
+	case "vector":
+		*et = ValVector
+	case "matrix":
+		*et = ValMatrix
+	case "string":
+		*et = ValString
+	default:
+		return fmt.Errorf("unknown value type %q", s)
+	}
+	return nil
+}
+
+func (e ValueType) String() string {
+	switch e {
+	case ValNone:
+		return "<ValNone>"
+	case ValScalar:
+		return "scalar"
+	case ValVector:
+		return "vector"
+	case ValMatrix:
+		return "matrix"
+	case ValString:
+		return "string"
+	}
+	panic("ValueType.String: unhandled value type")
+}
+
+// Scalar is a scalar value evaluated at the set timestamp.
+type Scalar struct {
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+func (s Scalar) String() string {
+	return fmt.Sprintf("scalar: %v @[%v]", s.Value, s.Timestamp)
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s Scalar) MarshalJSON() ([]byte, error) {
+	v := strconv.FormatFloat(float64(s.Value), 'f', -1, 64)
+	return json.Marshal([...]interface{}{s.Timestamp, string(v)})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *Scalar) UnmarshalJSON(b []byte) error {
+	var f string
+	v := [...]interface{}{&s.Timestamp, &f}
+
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+
+	value, err := strconv.ParseFloat(f, 64)
+	if err != nil {
+		return fmt.Errorf("error parsing sample value: %s", err)
+	}
+	s.Value = SampleValue(value)
+	return nil
+}
+
+// String is a string value evaluated at the set timestamp.
+type String struct {
+	Value     string `json:"value"`
+	Timestamp Time   `json:"timestamp"`
+}
+
+func (s *String) String() string {
+	return s.Value
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s String) MarshalJSON() ([]byte, error) {
+	return json.Marshal([]interface{}{s.Timestamp, s.Value})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *String) UnmarshalJSON(b []byte) error {
+	v := [...]interface{}{&s.Timestamp, &s.Value}
+	return json.Unmarshal(b, &v)
+}
+
+// Vector is basically only an alias for Samples, but the
+// contract is that in a Vector, all Samples have the same timestamp.
+type Vector []*Sample
+
+func (vec Vector) String() string {
+	entries := make([]string, len(vec))
+	for i, s := range vec {
+		entries[i] = s.String()
+	}
+	return strings.Join(entries, "\n")
+}
+
+func (vec Vector) Len() int      { return len(vec) }
+func (vec Vector) Swap(i, j int) { vec[i], vec[j] = vec[j], vec[i] }
+
+// Less compares first the metrics, then the timestamp.
+func (vec Vector) Less(i, j int) bool {
+	switch {
+	case vec[i].Metric.Before(vec[j].Metric):
+		return true
+	case vec[j].Metric.Before(vec[i].Metric):
+		return false
+	case vec[i].Timestamp.Before(vec[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (vec Vector) Equal(o Vector) bool {
+	if len(vec) != len(o) {
+		return false
+	}
+
+	for i, sample := range vec {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// Matrix is a list of time series.
+type Matrix []*SampleStream
+
+func (m Matrix) Len() int           { return len(m) }
+func (m Matrix) Less(i, j int) bool { return m[i].Metric.Before(m[j].Metric) }
+func (m Matrix) Swap(i, j int)      { m[i], m[j] = m[j], m[i] }
+
+func (mat Matrix) String() string {
+	matCp := make(Matrix, len(mat))
+	copy(matCp, mat)
+	sort.Sort(matCp)
+
+	strs := make([]string, len(matCp))
+
+	for i, ss := range matCp {
+		strs[i] = ss.String()
+	}
+
+	return strings.Join(strs, "\n")
+}

vendor/github.com/prometheus/procfs/.travis.yml

@@ -0,0 +1,7 @@
+sudo: false
+language: go
+go:
+    - 1.3
+    - 1.4
+    - 1.5
+    - tip

vendor/github.com/prometheus/procfs/AUTHORS.md

@@ -0,0 +1,20 @@
+The Prometheus project was started by Matt T. Proud (emeritus) and
+Julius Volz in 2012.
+
+Maintainers of this repository:
+
+* Tobias Schmidt <ts@soundcloud.com>
+
+The following individuals have contributed code to this repository
+(listed in alphabetical order):
+
+* Armen Baghumian <abaghumian@noggin.com.au>
+* Bjoern Rabenstein <beorn@soundcloud.com>
+* David Cournapeau <cournape@gmail.com>
+* Ji-Hoon, Seol <jihoon.seol@gmail.com>
+* Jonas Große Sundrup <cherti@letopolis.de>
+* Julius Volz <julius@soundcloud.com>
+* Matthias Rampke <mr@soundcloud.com>
+* Nicky Gerritsen <nicky@streamone.nl>
+* Rémi Audebert <contact@halfr.net>
+* Tobias Schmidt <tobidt@gmail.com>

vendor/github.com/prometheus/procfs/CONTRIBUTING.md

@@ -0,0 +1,18 @@
+# Contributing
+
+Prometheus uses GitHub to manage reviews of pull requests.
+
+* If you have a trivial fix or improvement, go ahead and create a pull
+  request, addressing (with `@...`) one or more of the maintainers
+  (see [AUTHORS.md](AUTHORS.md)) in the description of the pull request.
+
+* If you plan to do something more involved, first discuss your ideas
+  on our [mailing list](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).
+  This will avoid unnecessary work and surely give you and us a good deal
+  of inspiration.
+
+* Relevant coding style guidelines are the [Go Code Review
+  Comments](https://code.google.com/p/go-wiki/wiki/CodeReviewComments)
+  and the _Formatting and style_ section of Peter Bourgon's [Go: Best
+  Practices for Production
+  Environments](http://peter.bourgon.org/go-in-production/#formatting-and-style).

vendor/github.com/prometheus/procfs/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/procfs/Makefile

@@ -0,0 +1,6 @@
+ci:
+	go fmt
+	go vet
+	go test -v ./...
+	go get github.com/golang/lint/golint
+	golint *.go

vendor/github.com/prometheus/procfs/NOTICE

@@ -0,0 +1,7 @@
+procfs provides functions to retrieve system, kernel and process
+metrics from the pseudo-filesystem proc.
+
+Copyright 2014-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).

vendor/github.com/prometheus/procfs/README.md

@@ -0,0 +1,10 @@
+# procfs
+
+This procfs package provides functions to retrieve system, kernel and process
+metrics from the pseudo-filesystem proc.
+
+*WARNING*: This package is a work in progress. Its API may still break in
+backwards-incompatible ways without warnings. Use it at your own risk.
+
+[![GoDoc](https://godoc.org/github.com/prometheus/procfs?status.png)](https://godoc.org/github.com/prometheus/procfs)
+[![Build Status](https://travis-ci.org/prometheus/procfs.svg?branch=master)](https://travis-ci.org/prometheus/procfs)

vendor/github.com/prometheus/procfs/doc.go

@@ -0,0 +1,45 @@
+// Copyright 2014 Prometheus Team
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package procfs provides functions to retrieve system, kernel and process
+// metrics from the pseudo-filesystem proc.
+//
+// Example:
+//
+//    package main
+//
+//    import (
+//    	"fmt"
+//    	"log"
+//
+//    	"github.com/prometheus/procfs"
+//    )
+//
+//    func main() {
+//    	p, err := procfs.Self()
+//    	if err != nil {
+//    		log.Fatalf("could not get process: %s", err)
+//    	}
+//
+//    	stat, err := p.NewStat()
+//    	if err != nil {
+//    		log.Fatalf("could not get process stat: %s", err)
+//    	}
+//
+//    	fmt.Printf("command:  %s\n", stat.Comm)
+//    	fmt.Printf("cpu time: %fs\n", stat.CPUTime())
+//    	fmt.Printf("vsize:    %dB\n", stat.VirtualMemory())
+//    	fmt.Printf("rss:      %dB\n", stat.ResidentMemory())
+//    }
+//
+package procfs

vendor/github.com/prometheus/procfs/fs.go

@@ -0,0 +1,40 @@
+package procfs
+
+import (
+	"fmt"
+	"os"
+	"path"
+)
+
+// FS represents the pseudo-filesystem proc, which provides an interface to
+// kernel data structures.
+type FS string
+
+// DefaultMountPoint is the common mount point of the proc filesystem.
+const DefaultMountPoint = "/proc"
+
+// NewFS returns a new FS mounted under the given mountPoint. It will error
+// if the mount point can't be read.
+func NewFS(mountPoint string) (FS, error) {
+	info, err := os.Stat(mountPoint)
+	if err != nil {
+		return "", fmt.Errorf("could not read %s: %s", mountPoint, err)
+	}
+	if !info.IsDir() {
+		return "", fmt.Errorf("mount point %s is not a directory", mountPoint)
+	}
+
+	return FS(mountPoint), nil
+}
+
+func (fs FS) stat(p string) (os.FileInfo, error) {
+	return os.Stat(path.Join(string(fs), p))
+}
+
+func (fs FS) open(p string) (*os.File, error) {
+	return os.Open(path.Join(string(fs), p))
+}
+
+func (fs FS) readlink(p string) (string, error) {
+	return os.Readlink(path.Join(string(fs), p))
+}

vendor/github.com/prometheus/procfs/ipvs.go

@@ -0,0 +1,223 @@
+package procfs
+
+import (
+	"bufio"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"strconv"
+	"strings"
+)
+
+// IPVSStats holds IPVS statistics, as exposed by the kernel in `/proc/net/ip_vs_stats`.
+type IPVSStats struct {
+	// Total count of connections.
+	Connections uint64
+	// Total incoming packages processed.
+	IncomingPackets uint64
+	// Total outgoing packages processed.
+	OutgoingPackets uint64
+	// Total incoming traffic.
+	IncomingBytes uint64
+	// Total outgoing traffic.
+	OutgoingBytes uint64
+}
+
+// IPVSBackendStatus holds current metrics of one virtual / real address pair.
+type IPVSBackendStatus struct {
+	// The local (virtual) IP address.
+	LocalAddress net.IP
+	// The local (virtual) port.
+	LocalPort uint16
+	// The transport protocol (TCP, UDP).
+	Proto string
+	// The remote (real) IP address.
+	RemoteAddress net.IP
+	// The remote (real) port.
+	RemotePort uint16
+	// The current number of active connections for this virtual/real address pair.
+	ActiveConn uint64
+	// The current number of inactive connections for this virtual/real address pair.
+	InactConn uint64
+	// The current weight of this virtual/real address pair.
+	Weight uint64
+}
+
+// NewIPVSStats reads the IPVS statistics.
+func NewIPVSStats() (IPVSStats, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	return fs.NewIPVSStats()
+}
+
+// NewIPVSStats reads the IPVS statistics from the specified `proc` filesystem.
+func (fs FS) NewIPVSStats() (IPVSStats, error) {
+	file, err := fs.open("net/ip_vs_stats")
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	defer file.Close()
+
+	return parseIPVSStats(file)
+}
+
+// parseIPVSStats performs the actual parsing of `ip_vs_stats`.
+func parseIPVSStats(file io.Reader) (IPVSStats, error) {
+	var (
+		statContent []byte
+		statLines   []string
+		statFields  []string
+		stats       IPVSStats
+	)
+
+	statContent, err := ioutil.ReadAll(file)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	statLines = strings.SplitN(string(statContent), "\n", 4)
+	if len(statLines) != 4 {
+		return IPVSStats{}, errors.New("ip_vs_stats corrupt: too short")
+	}
+
+	statFields = strings.Fields(statLines[2])
+	if len(statFields) != 5 {
+		return IPVSStats{}, errors.New("ip_vs_stats corrupt: unexpected number of fields")
+	}
+
+	stats.Connections, err = strconv.ParseUint(statFields[0], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.IncomingPackets, err = strconv.ParseUint(statFields[1], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.OutgoingPackets, err = strconv.ParseUint(statFields[2], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.IncomingBytes, err = strconv.ParseUint(statFields[3], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.OutgoingBytes, err = strconv.ParseUint(statFields[4], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	return stats, nil
+}
+
+// NewIPVSBackendStatus reads and returns the status of all (virtual,real) server pairs.
+func NewIPVSBackendStatus() ([]IPVSBackendStatus, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return []IPVSBackendStatus{}, err
+	}
+
+	return fs.NewIPVSBackendStatus()
+}
+
+// NewIPVSBackendStatus reads and returns the status of all (virtual,real) server pairs from the specified `proc` filesystem.
+func (fs FS) NewIPVSBackendStatus() ([]IPVSBackendStatus, error) {
+	file, err := fs.open("net/ip_vs")
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseIPVSBackendStatus(file)
+}
+
+func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
+	var (
+		status       []IPVSBackendStatus
+		scanner      = bufio.NewScanner(file)
+		proto        string
+		localAddress net.IP
+		localPort    uint16
+		err          error
+	)
+
+	for scanner.Scan() {
+		fields := strings.Fields(string(scanner.Text()))
+		if len(fields) == 0 {
+			continue
+		}
+		switch {
+		case fields[0] == "IP" || fields[0] == "Prot" || fields[1] == "RemoteAddress:Port":
+			continue
+		case fields[0] == "TCP" || fields[0] == "UDP":
+			if len(fields) < 2 {
+				continue
+			}
+			proto = fields[0]
+			localAddress, localPort, err = parseIPPort(fields[1])
+			if err != nil {
+				return nil, err
+			}
+		case fields[0] == "->":
+			if len(fields) < 6 {
+				continue
+			}
+			remoteAddress, remotePort, err := parseIPPort(fields[1])
+			if err != nil {
+				return nil, err
+			}
+			weight, err := strconv.ParseUint(fields[3], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			activeConn, err := strconv.ParseUint(fields[4], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			inactConn, err := strconv.ParseUint(fields[5], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			status = append(status, IPVSBackendStatus{
+				LocalAddress:  localAddress,
+				LocalPort:     localPort,
+				RemoteAddress: remoteAddress,
+				RemotePort:    remotePort,
+				Proto:         proto,
+				Weight:        weight,
+				ActiveConn:    activeConn,
+				InactConn:     inactConn,
+			})
+		}
+	}
+	return status, nil
+}
+
+func parseIPPort(s string) (net.IP, uint16, error) {
+	tmp := strings.SplitN(s, ":", 2)
+
+	if len(tmp) != 2 {
+		return nil, 0, fmt.Errorf("invalid IP:Port: %s", s)
+	}
+
+	if len(tmp[0]) != 8 && len(tmp[0]) != 32 {
+		return nil, 0, fmt.Errorf("invalid IP: %s", tmp[0])
+	}
+
+	ip, err := hex.DecodeString(tmp[0])
+	if err != nil {
+		return nil, 0, err
+	}
+
+	port, err := strconv.ParseUint(tmp[1], 16, 16)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	return ip, uint16(port), nil
+}

vendor/github.com/prometheus/procfs/mdstat.go

@@ -0,0 +1,158 @@
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"path"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var (
+	statuslineRE = regexp.MustCompile(`(\d+) blocks .*\[(\d+)/(\d+)\] \[[U_]+\]`)
+	buildlineRE  = regexp.MustCompile(`\((\d+)/\d+\)`)
+)
+
+// MDStat holds info parsed from /proc/mdstat.
+type MDStat struct {
+	// Name of the device.
+	Name string
+	// activity-state of the device.
+	ActivityState string
+	// Number of active disks.
+	DisksActive int64
+	// Total number of disks the device consists of.
+	DisksTotal int64
+	// Number of blocks the device holds.
+	BlocksTotal int64
+	// Number of blocks on the device that are in sync.
+	BlocksSynced int64
+}
+
+// ParseMDStat parses an mdstat-file and returns a struct with the relevant infos.
+func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
+	mdStatusFilePath := path.Join(string(fs), "mdstat")
+	content, err := ioutil.ReadFile(mdStatusFilePath)
+	if err != nil {
+		return []MDStat{}, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+	}
+
+	mdStatusFile := string(content)
+
+	lines := strings.Split(mdStatusFile, "\n")
+	var currentMD string
+
+	// Each md has at least the deviceline, statusline and one empty line afterwards
+	// so we will have probably something of the order len(lines)/3 devices
+	// so we use that for preallocation.
+	estimateMDs := len(lines) / 3
+	mdStates := make([]MDStat, 0, estimateMDs)
+
+	for i, l := range lines {
+		if l == "" {
+			// Skip entirely empty lines.
+			continue
+		}
+
+		if l[0] == ' ' {
+			// Those lines are not the beginning of a md-section.
+			continue
+		}
+
+		if strings.HasPrefix(l, "Personalities") || strings.HasPrefix(l, "unused") {
+			// We aren't interested in lines with general info.
+			continue
+		}
+
+		mainLine := strings.Split(l, " ")
+		if len(mainLine) < 3 {
+			return mdStates, fmt.Errorf("error parsing mdline: %s", l)
+		}
+		currentMD = mainLine[0]      // name of md-device
+		activityState := mainLine[2] // activity status of said md-device
+
+		if len(lines) <= i+3 {
+			return mdStates, fmt.Errorf("error parsing %s: entry for %s has fewer lines than expected", mdStatusFilePath, currentMD)
+		}
+
+		active, total, size, err := evalStatusline(lines[i+1]) // parse statusline, always present
+		if err != nil {
+			return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+		}
+
+		//
+		// Now get the number of synced blocks.
+		//
+
+		// Get the line number of the syncing-line.
+		var j int
+		if strings.Contains(lines[i+2], "bitmap") { // then skip the bitmap line
+			j = i + 3
+		} else {
+			j = i + 2
+		}
+
+		// If device is syncing at the moment, get the number of currently synced bytes,
+		// otherwise that number equals the size of the device.
+		syncedBlocks := size
+		if strings.Contains(lines[j], "recovery") || strings.Contains(lines[j], "resync") {
+			syncedBlocks, err = evalBuildline(lines[j])
+			if err != nil {
+				return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+			}
+		}
+
+		mdStates = append(mdStates, MDStat{currentMD, activityState, active, total, size, syncedBlocks})
+
+	}
+
+	return mdStates, nil
+}
+
+func evalStatusline(statusline string) (active, total, size int64, err error) {
+	matches := statuslineRE.FindStringSubmatch(statusline)
+
+	// +1 to make it more obvious that the whole string containing the info is also returned as matches[0].
+	if len(matches) != 3+1 {
+		return 0, 0, 0, fmt.Errorf("unexpected number matches found in statusline: %s", statusline)
+	}
+
+	size, err = strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
+	}
+
+	total, err = strconv.ParseInt(matches[2], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
+	}
+
+	active, err = strconv.ParseInt(matches[3], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
+	}
+
+	return active, total, size, nil
+}
+
+// Gets the size that has already been synced out of the sync-line.
+func evalBuildline(buildline string) (int64, error) {
+	matches := buildlineRE.FindStringSubmatch(buildline)
+
+	// +1 to make it more obvious that the whole string containing the info is also returned as matches[0].
+	if len(matches) < 1+1 {
+		return 0, fmt.Errorf("too few matches found in buildline: %s", buildline)
+	}
+
+	if len(matches) > 1+1 {
+		return 0, fmt.Errorf("too many matches found in buildline: %s", buildline)
+	}
+
+	syncedSize, err := strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("%s in buildline: %s", err, buildline)
+	}
+
+	return syncedSize, nil
+}

vendor/github.com/prometheus/procfs/proc.go

@@ -0,0 +1,188 @@
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"strconv"
+	"strings"
+)
+
+// Proc provides information about a running process.
+type Proc struct {
+	// The process ID.
+	PID int
+
+	fs FS
+}
+
+// Procs represents a list of Proc structs.
+type Procs []Proc
+
+func (p Procs) Len() int           { return len(p) }
+func (p Procs) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+func (p Procs) Less(i, j int) bool { return p[i].PID < p[j].PID }
+
+// Self returns a process for the current process.
+func Self() (Proc, error) {
+	return NewProc(os.Getpid())
+}
+
+// NewProc returns a process for the given pid under /proc.
+func NewProc(pid int) (Proc, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Proc{}, err
+	}
+
+	return fs.NewProc(pid)
+}
+
+// AllProcs returns a list of all currently avaible processes under /proc.
+func AllProcs() (Procs, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Procs{}, err
+	}
+
+	return fs.AllProcs()
+}
+
+// NewProc returns a process for the given pid.
+func (fs FS) NewProc(pid int) (Proc, error) {
+	if _, err := fs.stat(strconv.Itoa(pid)); err != nil {
+		return Proc{}, err
+	}
+
+	return Proc{PID: pid, fs: fs}, nil
+}
+
+// AllProcs returns a list of all currently avaible processes.
+func (fs FS) AllProcs() (Procs, error) {
+	d, err := fs.open("")
+	if err != nil {
+		return Procs{}, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return Procs{}, fmt.Errorf("could not read %s: %s", d.Name(), err)
+	}
+
+	p := Procs{}
+	for _, n := range names {
+		pid, err := strconv.ParseInt(n, 10, 64)
+		if err != nil {
+			continue
+		}
+		p = append(p, Proc{PID: int(pid), fs: fs})
+	}
+
+	return p, nil
+}
+
+// CmdLine returns the command line of a process.
+func (p Proc) CmdLine() ([]string, error) {
+	f, err := p.open("cmdline")
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(data) < 1 {
+		return []string{}, nil
+	}
+
+	return strings.Split(string(data[:len(data)-1]), string(byte(0))), nil
+}
+
+// Executable returns the absolute path of the executable command of a process.
+func (p Proc) Executable() (string, error) {
+	exe, err := p.readlink("exe")
+
+	if os.IsNotExist(err) {
+		return "", nil
+	}
+
+	return exe, err
+}
+
+// FileDescriptors returns the currently open file descriptors of a process.
+func (p Proc) FileDescriptors() ([]uintptr, error) {
+	names, err := p.fileDescriptors()
+	if err != nil {
+		return nil, err
+	}
+
+	fds := make([]uintptr, len(names))
+	for i, n := range names {
+		fd, err := strconv.ParseInt(n, 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("could not parse fd %s: %s", n, err)
+		}
+		fds[i] = uintptr(fd)
+	}
+
+	return fds, nil
+}
+
+// FileDescriptorTargets returns the targets of all file descriptors of a process.
+// If a file descriptor is not a symlink to a file (like a socket), that value will be the empty string.
+func (p Proc) FileDescriptorTargets() ([]string, error) {
+	names, err := p.fileDescriptors()
+	if err != nil {
+		return nil, err
+	}
+
+	targets := make([]string, len(names))
+
+	for i, name := range names {
+		target, err := p.readlink("fd/" + name)
+		if err == nil {
+			targets[i] = target
+		}
+	}
+
+	return targets, nil
+}
+
+// FileDescriptorsLen returns the number of currently open file descriptors of
+// a process.
+func (p Proc) FileDescriptorsLen() (int, error) {
+	fds, err := p.fileDescriptors()
+	if err != nil {
+		return 0, err
+	}
+
+	return len(fds), nil
+}
+
+func (p Proc) fileDescriptors() ([]string, error) {
+	d, err := p.open("fd")
+	if err != nil {
+		return nil, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("could not read %s: %s", d.Name(), err)
+	}
+
+	return names, nil
+}
+
+func (p Proc) open(pa string) (*os.File, error) {
+	return p.fs.open(path.Join(strconv.Itoa(p.PID), pa))
+}
+
+func (p Proc) readlink(pa string) (string, error) {
+	return p.fs.readlink(path.Join(strconv.Itoa(p.PID), pa))
+}

vendor/github.com/prometheus/procfs/proc_io.go

@@ -0,0 +1,54 @@
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+)
+
+// ProcIO models the content of /proc/<pid>/io.
+type ProcIO struct {
+	// Chars read.
+	RChar uint64
+	// Chars written.
+	WChar uint64
+	// Read syscalls.
+	SyscR uint64
+	// Write syscalls.
+	SyscW uint64
+	// Bytes read.
+	ReadBytes uint64
+	// Bytes written.
+	WriteBytes uint64
+	// Bytes written, but taking into account truncation. See
+	// Documentation/filesystems/proc.txt in the kernel sources for
+	// detailed explanation.
+	CancelledWriteBytes int64
+}
+
+// NewIO creates a new ProcIO instance from a given Proc instance.
+func (p Proc) NewIO() (ProcIO, error) {
+	pio := ProcIO{}
+
+	f, err := p.open("io")
+	if err != nil {
+		return pio, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return pio, err
+	}
+
+	ioFormat := "rchar: %d\nwchar: %d\nsyscr: %d\nsyscw: %d\n" +
+		"read_bytes: %d\nwrite_bytes: %d\n" +
+		"cancelled_write_bytes: %d\n"
+
+	_, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR,
+		&pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes)
+	if err != nil {
+		return pio, err
+	}
+
+	return pio, nil
+}

vendor/github.com/prometheus/procfs/proc_limits.go

@@ -0,0 +1,111 @@
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"regexp"
+	"strconv"
+)
+
+// ProcLimits represents the soft limits for each of the process's resource
+// limits.
+type ProcLimits struct {
+	CPUTime          int
+	FileSize         int
+	DataSize         int
+	StackSize        int
+	CoreFileSize     int
+	ResidentSet      int
+	Processes        int
+	OpenFiles        int
+	LockedMemory     int
+	AddressSpace     int
+	FileLocks        int
+	PendingSignals   int
+	MsqqueueSize     int
+	NicePriority     int
+	RealtimePriority int
+	RealtimeTimeout  int
+}
+
+const (
+	limitsFields    = 3
+	limitsUnlimited = "unlimited"
+)
+
+var (
+	limitsDelimiter = regexp.MustCompile("  +")
+)
+
+// NewLimits returns the current soft limits of the process.
+func (p Proc) NewLimits() (ProcLimits, error) {
+	f, err := p.open("limits")
+	if err != nil {
+		return ProcLimits{}, err
+	}
+	defer f.Close()
+
+	var (
+		l = ProcLimits{}
+		s = bufio.NewScanner(f)
+	)
+	for s.Scan() {
+		fields := limitsDelimiter.Split(s.Text(), limitsFields)
+		if len(fields) != limitsFields {
+			return ProcLimits{}, fmt.Errorf(
+				"couldn't parse %s line %s", f.Name(), s.Text())
+		}
+
+		switch fields[0] {
+		case "Max cpu time":
+			l.CPUTime, err = parseInt(fields[1])
+		case "Max file size":
+			l.FileLocks, err = parseInt(fields[1])
+		case "Max data size":
+			l.DataSize, err = parseInt(fields[1])
+		case "Max stack size":
+			l.StackSize, err = parseInt(fields[1])
+		case "Max core file size":
+			l.CoreFileSize, err = parseInt(fields[1])
+		case "Max resident set":
+			l.ResidentSet, err = parseInt(fields[1])
+		case "Max processes":
+			l.Processes, err = parseInt(fields[1])
+		case "Max open files":
+			l.OpenFiles, err = parseInt(fields[1])
+		case "Max locked memory":
+			l.LockedMemory, err = parseInt(fields[1])
+		case "Max address space":
+			l.AddressSpace, err = parseInt(fields[1])
+		case "Max file locks":
+			l.FileLocks, err = parseInt(fields[1])
+		case "Max pending signals":
+			l.PendingSignals, err = parseInt(fields[1])
+		case "Max msgqueue size":
+			l.MsqqueueSize, err = parseInt(fields[1])
+		case "Max nice priority":
+			l.NicePriority, err = parseInt(fields[1])
+		case "Max realtime priority":
+			l.RealtimePriority, err = parseInt(fields[1])
+		case "Max realtime timeout":
+			l.RealtimeTimeout, err = parseInt(fields[1])
+		}
+
+		if err != nil {
+			return ProcLimits{}, err
+		}
+	}
+
+	return l, s.Err()
+}
+
+func parseInt(s string) (int, error) {
+	if s == limitsUnlimited {
+		return -1, nil
+	}
+	i, err := strconv.ParseInt(s, 10, 32)
+	if err != nil {
+		return 0, fmt.Errorf("couldn't parse value %s: %s", s, err)
+	}
+	return int(i), nil
+}

vendor/github.com/prometheus/procfs/proc_stat.go

@@ -0,0 +1,175 @@
+package procfs
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+)
+
+// Originally, this USER_HZ value was dynamically retrieved via a sysconf call which
+// required cgo. However, that caused a lot of problems regarding
+// cross-compilation. Alternatives such as running a binary to determine the
+// value, or trying to derive it in some other way were all problematic.
+// After much research it was determined that USER_HZ is actually hardcoded to
+// 100 on all Go-supported platforms as of the time of this writing. This is
+// why we decided to hardcode it here as well. It is not impossible that there
+// could be systems with exceptions, but they should be very exotic edge cases,
+// and in that case, the worst outcome will be two misreported metrics.
+//
+// See also the following discussions:
+//
+// - https://github.com/prometheus/node_exporter/issues/52
+// - https://github.com/prometheus/procfs/pull/2
+// - http://stackoverflow.com/questions/17410841/how-does-user-hz-solve-the-jiffy-scaling-issue
+const userHZ = 100
+
+// ProcStat provides status information about the process,
+// read from /proc/[pid]/stat.
+type ProcStat struct {
+	// The process ID.
+	PID int
+	// The filename of the executable.
+	Comm string
+	// The process state.
+	State string
+	// The PID of the parent of this process.
+	PPID int
+	// The process group ID of the process.
+	PGRP int
+	// The session ID of the process.
+	Session int
+	// The controlling terminal of the process.
+	TTY int
+	// The ID of the foreground process group of the controlling terminal of
+	// the process.
+	TPGID int
+	// The kernel flags word of the process.
+	Flags uint
+	// The number of minor faults the process has made which have not required
+	// loading a memory page from disk.
+	MinFlt uint
+	// The number of minor faults that the process's waited-for children have
+	// made.
+	CMinFlt uint
+	// The number of major faults the process has made which have required
+	// loading a memory page from disk.
+	MajFlt uint
+	// The number of major faults that the process's waited-for children have
+	// made.
+	CMajFlt uint
+	// Amount of time that this process has been scheduled in user mode,
+	// measured in clock ticks.
+	UTime uint
+	// Amount of time that this process has been scheduled in kernel mode,
+	// measured in clock ticks.
+	STime uint
+	// Amount of time that this process's waited-for children have been
+	// scheduled in user mode, measured in clock ticks.
+	CUTime uint
+	// Amount of time that this process's waited-for children have been
+	// scheduled in kernel mode, measured in clock ticks.
+	CSTime uint
+	// For processes running a real-time scheduling policy, this is the negated
+	// scheduling priority, minus one.
+	Priority int
+	// The nice value, a value in the range 19 (low priority) to -20 (high
+	// priority).
+	Nice int
+	// Number of threads in this process.
+	NumThreads int
+	// The time the process started after system boot, the value is expressed
+	// in clock ticks.
+	Starttime uint64
+	// Virtual memory size in bytes.
+	VSize int
+	// Resident set size in pages.
+	RSS int
+
+	fs FS
+}
+
+// NewStat returns the current status information of the process.
+func (p Proc) NewStat() (ProcStat, error) {
+	f, err := p.open("stat")
+	if err != nil {
+		return ProcStat{}, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return ProcStat{}, err
+	}
+
+	var (
+		ignore int
+
+		s = ProcStat{PID: p.PID, fs: p.fs}
+		l = bytes.Index(data, []byte("("))
+		r = bytes.LastIndex(data, []byte(")"))
+	)
+
+	if l < 0 || r < 0 {
+		return ProcStat{}, fmt.Errorf(
+			"unexpected format, couldn't extract comm: %s",
+			data,
+		)
+	}
+
+	s.Comm = string(data[l+1 : r])
+	_, err = fmt.Fscan(
+		bytes.NewBuffer(data[r+2:]),
+		&s.State,
+		&s.PPID,
+		&s.PGRP,
+		&s.Session,
+		&s.TTY,
+		&s.TPGID,
+		&s.Flags,
+		&s.MinFlt,
+		&s.CMinFlt,
+		&s.MajFlt,
+		&s.CMajFlt,
+		&s.UTime,
+		&s.STime,
+		&s.CUTime,
+		&s.CSTime,
+		&s.Priority,
+		&s.Nice,
+		&s.NumThreads,
+		&ignore,
+		&s.Starttime,
+		&s.VSize,
+		&s.RSS,
+	)
+	if err != nil {
+		return ProcStat{}, err
+	}
+
+	return s, nil
+}
+
+// VirtualMemory returns the virtual memory size in bytes.
+func (s ProcStat) VirtualMemory() int {
+	return s.VSize
+}
+
+// ResidentMemory returns the resident memory size in bytes.
+func (s ProcStat) ResidentMemory() int {
+	return s.RSS * os.Getpagesize()
+}
+
+// StartTime returns the unix timestamp of the process in seconds.
+func (s ProcStat) StartTime() (float64, error) {
+	stat, err := s.fs.NewStat()
+	if err != nil {
+		return 0, err
+	}
+	return float64(stat.BootTime) + (float64(s.Starttime) / userHZ), nil
+}
+
+// CPUTime returns the total CPU user and system time in seconds.
+func (s ProcStat) CPUTime() float64 {
+	return float64(s.UTime+s.STime) / userHZ
+}

vendor/github.com/prometheus/procfs/stat.go

@@ -0,0 +1,55 @@
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Stat represents kernel/system statistics.
+type Stat struct {
+	// Boot time in seconds since the Epoch.
+	BootTime int64
+}
+
+// NewStat returns kernel/system statistics read from /proc/stat.
+func NewStat() (Stat, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Stat{}, err
+	}
+
+	return fs.NewStat()
+}
+
+// NewStat returns an information about current kernel/system statistics.
+func (fs FS) NewStat() (Stat, error) {
+	f, err := fs.open("stat")
+	if err != nil {
+		return Stat{}, err
+	}
+	defer f.Close()
+
+	s := bufio.NewScanner(f)
+	for s.Scan() {
+		line := s.Text()
+		if !strings.HasPrefix(line, "btime") {
+			continue
+		}
+		fields := strings.Fields(line)
+		if len(fields) != 2 {
+			return Stat{}, fmt.Errorf("couldn't parse %s line %s", f.Name(), line)
+		}
+		i, err := strconv.ParseInt(fields[1], 10, 32)
+		if err != nil {
+			return Stat{}, fmt.Errorf("couldn't parse %s: %s", fields[1], err)
+		}
+		return Stat{BootTime: i}, nil
+	}
+	if err := s.Err(); err != nil {
+		return Stat{}, fmt.Errorf("couldn't parse %s: %s", f.Name(), err)
+	}
+
+	return Stat{}, fmt.Errorf("couldn't parse %s, missing btime", f.Name())
+}

vendor/github.com/robfig/cron/.gitignore

@@ -0,0 +1,22 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe

vendor/github.com/robfig/cron/.travis.yml

@@ -0,0 +1 @@
+language: go

vendor/github.com/robfig/cron/LICENSE

@@ -0,0 +1,21 @@
+Copyright (C) 2012 Rob Figueiredo
+All Rights Reserved.
+
+MIT LICENSE
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.