mirror of
https://github.com/Luzifer/nginx-sso.git
synced 2024-12-23 22:31:17 +00:00
689 lines
22 KiB
Go
689 lines
22 KiB
Go
// Copyright 2017 Google LLC
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package firestore
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import (
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"context"
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"errors"
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"fmt"
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"io"
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"reflect"
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"sort"
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vkit "cloud.google.com/go/firestore/apiv1"
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"cloud.google.com/go/internal/trace"
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"google.golang.org/api/iterator"
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pb "google.golang.org/genproto/googleapis/firestore/v1"
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"google.golang.org/grpc/codes"
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"google.golang.org/grpc/status"
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)
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var errNilDocRef = errors.New("firestore: nil DocumentRef")
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// A DocumentRef is a reference to a Firestore document.
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type DocumentRef struct {
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// The CollectionRef that this document is a part of. Never nil.
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Parent *CollectionRef
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// The full resource path of the document. A document "doc-1" in collection
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// "coll-1" would be: "projects/P/databases/D/documents/coll-1/doc-1".
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Path string
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// The shorter resource path of the document. A document "doc-1" in
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// collection "coll-1" would be: "coll-1/doc-1".
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shortPath string
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// The ID of the document: the last component of the resource path.
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ID string
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}
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func newDocRef(parent *CollectionRef, id string) *DocumentRef {
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return &DocumentRef{
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Parent: parent,
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ID: id,
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Path: parent.Path + "/" + id,
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shortPath: parent.selfPath + "/" + id,
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}
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}
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// Collection returns a reference to sub-collection of this document.
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func (d *DocumentRef) Collection(id string) *CollectionRef {
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return newCollRefWithParent(d.Parent.c, d, id)
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}
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// Get retrieves the document. If the document does not exist, Get return a NotFound error, which
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// can be checked with
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// grpc.Code(err) == codes.NotFound
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// In that case, Get returns a non-nil DocumentSnapshot whose Exists method return false and whose
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// ReadTime is the time of the failed read operation.
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func (d *DocumentRef) Get(ctx context.Context) (_ *DocumentSnapshot, err error) {
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ctx = trace.StartSpan(ctx, "cloud.google.com/go/firestore.DocumentRef.Get")
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defer func() { trace.EndSpan(ctx, err) }()
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if d == nil {
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return nil, errNilDocRef
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}
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docsnaps, err := d.Parent.c.getAll(ctx, []*DocumentRef{d}, nil)
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if err != nil {
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return nil, err
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}
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ds := docsnaps[0]
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if !ds.Exists() {
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return ds, status.Errorf(codes.NotFound, "%q not found", d.Path)
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}
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return ds, nil
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}
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// Create creates the document with the given data.
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// It returns an error if a document with the same ID already exists.
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//
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// The data argument can be a map with string keys, a struct, or a pointer to a
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// struct. The map keys or exported struct fields become the fields of the firestore
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// document.
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// The values of data are converted to Firestore values as follows:
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//
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// - bool converts to Bool.
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// - string converts to String.
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// - int, int8, int16, int32 and int64 convert to Integer.
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// - uint8, uint16 and uint32 convert to Integer. uint, uint64 and uintptr are disallowed,
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// because they may be able to represent values that cannot be represented in an int64,
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// which is the underlying type of a Integer.
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// - float32 and float64 convert to Double.
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// - []byte converts to Bytes.
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// - time.Time and *ts.Timestamp convert to Timestamp. ts is the package
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// "github.com/golang/protobuf/ptypes/timestamp".
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// - *latlng.LatLng converts to GeoPoint. latlng is the package
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// "google.golang.org/genproto/googleapis/type/latlng". You should always use
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// a pointer to a LatLng.
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// - Slices convert to Array.
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// - *firestore.DocumentRef converts to Reference.
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// - Maps and structs convert to Map.
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// - nils of any type convert to Null.
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//
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// Pointers and interface{} are also permitted, and their elements processed
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// recursively.
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//
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// Struct fields can have tags like those used by the encoding/json package. Tags
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// begin with "firestore:" and are followed by "-", meaning "ignore this field," or
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// an alternative name for the field. Following the name, these comma-separated
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// options may be provided:
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//
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// - omitempty: Do not encode this field if it is empty. A value is empty
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// if it is a zero value, or an array, slice or map of length zero.
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// - serverTimestamp: The field must be of type time.Time. When writing, if
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// the field has the zero value, the server will populate the stored document with
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// the time that the request is processed.
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func (d *DocumentRef) Create(ctx context.Context, data interface{}) (_ *WriteResult, err error) {
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ctx = trace.StartSpan(ctx, "cloud.google.com/go/firestore.DocumentRef.Create")
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defer func() { trace.EndSpan(ctx, err) }()
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ws, err := d.newCreateWrites(data)
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if err != nil {
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return nil, err
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}
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return d.Parent.c.commit1(ctx, ws)
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}
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func (d *DocumentRef) newCreateWrites(data interface{}) ([]*pb.Write, error) {
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if d == nil {
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return nil, errNilDocRef
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}
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doc, transforms, err := toProtoDocument(data)
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if err != nil {
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return nil, err
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}
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doc.Name = d.Path
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pc, err := exists(false).preconditionProto()
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if err != nil {
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return nil, err
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}
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return d.newUpdateWithTransform(doc, nil, pc, transforms, false), nil
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}
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// Set creates or overwrites the document with the given data. See DocumentRef.Create
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// for the acceptable values of data. Without options, Set overwrites the document
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// completely. Specify one of the Merge options to preserve an existing document's
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// fields. To delete some fields, use a Merge option with firestore.Delete as the
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// field value.
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func (d *DocumentRef) Set(ctx context.Context, data interface{}, opts ...SetOption) (_ *WriteResult, err error) {
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ctx = trace.StartSpan(ctx, "cloud.google.com/go/firestore.DocumentRef.Set")
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defer func() { trace.EndSpan(ctx, err) }()
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ws, err := d.newSetWrites(data, opts)
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if err != nil {
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return nil, err
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}
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return d.Parent.c.commit1(ctx, ws)
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}
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func (d *DocumentRef) newSetWrites(data interface{}, opts []SetOption) ([]*pb.Write, error) {
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if d == nil {
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return nil, errNilDocRef
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}
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if data == nil {
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return nil, errors.New("firestore: nil document contents")
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}
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if len(opts) == 0 { // Set without merge
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doc, serverTimestampPaths, err := toProtoDocument(data)
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if err != nil {
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return nil, err
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}
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doc.Name = d.Path
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return d.newUpdateWithTransform(doc, nil, nil, serverTimestampPaths, true), nil
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}
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// Set with merge.
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// This is just like Update, except for the existence precondition.
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// So we turn data into a list of (FieldPath, interface{}) pairs (fpv's), as we do
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// for Update.
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fieldPaths, allPaths, err := processSetOptions(opts)
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if err != nil {
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return nil, err
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}
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var fpvs []fpv
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v := reflect.ValueOf(data)
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if allPaths {
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// Set with MergeAll. Collect all the leaves of the map.
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if v.Kind() != reflect.Map {
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return nil, errors.New("firestore: MergeAll can only be specified with map data")
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}
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if v.Len() == 0 {
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// Special case: MergeAll with an empty map.
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return d.newUpdateWithTransform(&pb.Document{Name: d.Path}, []FieldPath{}, nil, nil, true), nil
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}
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fpvsFromData(v, nil, &fpvs)
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} else {
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// Set with merge paths. Collect only the values at the given paths.
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for _, fp := range fieldPaths {
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val, err := getAtPath(v, fp)
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if err != nil {
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return nil, err
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}
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fpvs = append(fpvs, fpv{fp, val})
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}
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}
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return d.fpvsToWrites(fpvs, nil)
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}
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// fpvsFromData converts v into a list of (FieldPath, value) pairs.
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func fpvsFromData(v reflect.Value, prefix FieldPath, fpvs *[]fpv) {
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switch v.Kind() {
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case reflect.Map:
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for _, k := range v.MapKeys() {
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fpvsFromData(v.MapIndex(k), prefix.with(k.String()), fpvs)
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}
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case reflect.Interface:
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fpvsFromData(v.Elem(), prefix, fpvs)
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default:
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var val interface{}
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if v.IsValid() {
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val = v.Interface()
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}
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*fpvs = append(*fpvs, fpv{prefix, val})
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}
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}
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// Delete deletes the document. If the document doesn't exist, it does nothing
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// and returns no error.
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func (d *DocumentRef) Delete(ctx context.Context, preconds ...Precondition) (_ *WriteResult, err error) {
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ctx = trace.StartSpan(ctx, "cloud.google.com/go/firestore.DocumentRef.Delete")
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defer func() { trace.EndSpan(ctx, err) }()
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ws, err := d.newDeleteWrites(preconds)
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if err != nil {
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return nil, err
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}
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return d.Parent.c.commit1(ctx, ws)
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}
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func (d *DocumentRef) newDeleteWrites(preconds []Precondition) ([]*pb.Write, error) {
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if d == nil {
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return nil, errNilDocRef
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}
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pc, err := processPreconditionsForDelete(preconds)
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if err != nil {
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return nil, err
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}
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return []*pb.Write{{
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Operation: &pb.Write_Delete{d.Path},
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CurrentDocument: pc,
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}}, nil
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}
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func (d *DocumentRef) newUpdatePathWrites(updates []Update, preconds []Precondition) ([]*pb.Write, error) {
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if len(updates) == 0 {
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return nil, errors.New("firestore: no paths to update")
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}
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var fpvs []fpv
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for _, u := range updates {
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v, err := u.process()
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if err != nil {
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return nil, err
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}
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fpvs = append(fpvs, v)
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}
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pc, err := processPreconditionsForUpdate(preconds)
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if err != nil {
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return nil, err
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}
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return d.fpvsToWrites(fpvs, pc)
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}
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func (d *DocumentRef) fpvsToWrites(fpvs []fpv, pc *pb.Precondition) ([]*pb.Write, error) {
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// Make sure there are no duplications or prefixes among the field paths.
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var fps []FieldPath
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for _, fpv := range fpvs {
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fps = append(fps, fpv.fieldPath)
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}
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if err := checkNoDupOrPrefix(fps); err != nil {
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return nil, err
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}
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// Process each fpv.
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var updatePaths []FieldPath
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var transforms []*pb.DocumentTransform_FieldTransform
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doc := &pb.Document{
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Name: d.Path,
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Fields: map[string]*pb.Value{},
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}
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for _, fpv := range fpvs {
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switch fpv.value.(type) {
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case arrayUnion:
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au := fpv.value.(arrayUnion)
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t, err := arrayUnionTransform(au, fpv.fieldPath)
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if err != nil {
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return nil, err
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}
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transforms = append(transforms, t)
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case arrayRemove:
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ar := fpv.value.(arrayRemove)
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t, err := arrayRemoveTransform(ar, fpv.fieldPath)
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if err != nil {
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return nil, err
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}
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transforms = append(transforms, t)
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default:
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switch fpv.value {
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case Delete:
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// Send the field path without a corresponding value.
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updatePaths = append(updatePaths, fpv.fieldPath)
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case ServerTimestamp:
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// Use the path in a transform operation.
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transforms = append(transforms, serverTimestamp(fpv.fieldPath.toServiceFieldPath()))
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default:
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updatePaths = append(updatePaths, fpv.fieldPath)
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// Convert the value to a proto and put it into the document.
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v := reflect.ValueOf(fpv.value)
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pv, _, err := toProtoValue(v)
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if err != nil {
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return nil, err
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}
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setAtPath(doc.Fields, fpv.fieldPath, pv)
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// Also accumulate any transforms within the value.
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ts, err := extractTransforms(v, fpv.fieldPath)
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if err != nil {
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return nil, err
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}
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transforms = append(transforms, ts...)
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}
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}
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}
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return d.newUpdateWithTransform(doc, updatePaths, pc, transforms, false), nil
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}
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// newUpdateWithTransform constructs operations for a commit. Most generally, it
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// returns an update operation followed by a transform.
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//
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// If there are no serverTimestampPaths, the transform is omitted.
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//
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// If doc.Fields is empty, there are no updatePaths, and there is no precondition,
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// the update is omitted, unless updateOnEmpty is true.
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func (d *DocumentRef) newUpdateWithTransform(doc *pb.Document, updatePaths []FieldPath, pc *pb.Precondition, transforms []*pb.DocumentTransform_FieldTransform, updateOnEmpty bool) []*pb.Write {
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var ws []*pb.Write
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if updateOnEmpty || len(doc.Fields) > 0 ||
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len(updatePaths) > 0 || (pc != nil && len(transforms) == 0) {
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var mask *pb.DocumentMask
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if updatePaths != nil {
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sfps := toServiceFieldPaths(updatePaths)
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sort.Strings(sfps) // TODO(jba): make tests pass without this
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mask = &pb.DocumentMask{FieldPaths: sfps}
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}
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w := &pb.Write{
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Operation: &pb.Write_Update{doc},
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UpdateMask: mask,
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CurrentDocument: pc,
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}
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ws = append(ws, w)
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pc = nil // If the precondition is in the write, we don't need it in the transform.
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}
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if len(transforms) > 0 || pc != nil {
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ws = append(ws, &pb.Write{
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Operation: &pb.Write_Transform{
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Transform: &pb.DocumentTransform{
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Document: d.Path,
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FieldTransforms: transforms,
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},
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},
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CurrentDocument: pc,
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})
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}
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return ws
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}
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// arrayUnion is a special type in firestore. It instructs the server to add its
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// elements to whatever array already exists, or to create an array if no value
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// exists.
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type arrayUnion struct {
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elems []interface{}
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}
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// ArrayUnion specifies elements to be added to whatever array already exists in
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// the server, or to create an array if no value exists.
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//
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// If a value exists and it's an array, values are appended to it. Any duplicate
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// value is ignored.
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// If a value exists and it's not an array, the value is replaced by an array of
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// the values in the ArrayUnion.
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// If a value does not exist, an array of the values in the ArrayUnion is created.
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//
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// ArrayUnion must be the value of a field directly; it cannot appear in
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// array or struct values, or in any value that is itself inside an array or
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// struct.
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func ArrayUnion(elems ...interface{}) arrayUnion {
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return arrayUnion{elems: elems}
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}
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// This helper converts an arrayUnion into a proto object.
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func arrayUnionTransform(au arrayUnion, fp FieldPath) (*pb.DocumentTransform_FieldTransform, error) {
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var elems []*pb.Value
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for _, v := range au.elems {
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pv, _, err := toProtoValue(reflect.ValueOf(v))
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if err != nil {
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return nil, err
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}
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elems = append(elems, pv)
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}
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return &pb.DocumentTransform_FieldTransform{
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FieldPath: fp.toServiceFieldPath(),
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TransformType: &pb.DocumentTransform_FieldTransform_AppendMissingElements{
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AppendMissingElements: &pb.ArrayValue{Values: elems},
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},
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}, nil
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}
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// arrayRemove is a special type in firestore. It instructs the server to remove
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// the specified values.
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type arrayRemove struct {
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elems []interface{}
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}
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// ArrayRemove specifies elements to be removed from whatever array already
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// exists in the server.
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//
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// If a value exists and it's an array, values are removed from it. All
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// duplicate values are removed.
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// If a value exists and it's not an array, the value is replaced by an empty
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// array.
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// If a value does not exist, an empty array is created.
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//
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// ArrayRemove must be the value of a field directly; it cannot appear in
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// array or struct values, or in any value that is itself inside an array or
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// struct.
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func ArrayRemove(elems ...interface{}) arrayRemove {
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return arrayRemove{elems: elems}
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}
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// This helper converts an arrayRemove into a proto object.
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func arrayRemoveTransform(ar arrayRemove, fp FieldPath) (*pb.DocumentTransform_FieldTransform, error) {
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var elems []*pb.Value
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for _, v := range ar.elems {
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// ServerTimestamp cannot occur in an array, so we ignore transformations here.
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pv, _, err := toProtoValue(reflect.ValueOf(v))
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if err != nil {
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return nil, err
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}
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elems = append(elems, pv)
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}
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return &pb.DocumentTransform_FieldTransform{
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FieldPath: fp.toServiceFieldPath(),
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TransformType: &pb.DocumentTransform_FieldTransform_RemoveAllFromArray{
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RemoveAllFromArray: &pb.ArrayValue{Values: elems},
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},
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}, nil
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}
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type sentinel int
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const (
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// Delete is used as a value in a call to Update or Set with merge to indicate
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// that the corresponding key should be deleted.
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Delete sentinel = iota
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// ServerTimestamp is used as a value in a call to Update to indicate that the
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// key's value should be set to the time at which the server processed
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// the request.
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//
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// ServerTimestamp must be the value of a field directly; it cannot appear in
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// array or struct values, or in any value that is itself inside an array or
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// struct.
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ServerTimestamp
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)
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func (s sentinel) String() string {
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switch s {
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case Delete:
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return "Delete"
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case ServerTimestamp:
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return "ServerTimestamp"
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default:
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return "<?sentinel?>"
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}
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}
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||
// An Update describes an update to a value referred to by a path.
|
||
// An Update should have either a non-empty Path or a non-empty FieldPath,
|
||
// but not both.
|
||
//
|
||
// See DocumentRef.Create for acceptable values.
|
||
// To delete a field, specify firestore.Delete as the value.
|
||
type Update struct {
|
||
Path string // Will be split on dots, and must not contain any of "˜*/[]".
|
||
FieldPath FieldPath
|
||
Value interface{}
|
||
}
|
||
|
||
// An fpv is a pair of validated FieldPath and value.
|
||
type fpv struct {
|
||
fieldPath FieldPath
|
||
value interface{}
|
||
}
|
||
|
||
func (u *Update) process() (fpv, error) {
|
||
if (u.Path != "") == (u.FieldPath != nil) {
|
||
return fpv{}, fmt.Errorf("firestore: update %+v should have exactly one of Path or FieldPath", u)
|
||
}
|
||
fp := u.FieldPath
|
||
var err error
|
||
if fp == nil {
|
||
fp, err = parseDotSeparatedString(u.Path)
|
||
if err != nil {
|
||
return fpv{}, err
|
||
}
|
||
}
|
||
if err := fp.validate(); err != nil {
|
||
return fpv{}, err
|
||
}
|
||
return fpv{fp, u.Value}, nil
|
||
}
|
||
|
||
// Update updates the document. The values at the given
|
||
// field paths are replaced, but other fields of the stored document are untouched.
|
||
func (d *DocumentRef) Update(ctx context.Context, updates []Update, preconds ...Precondition) (_ *WriteResult, err error) {
|
||
ctx = trace.StartSpan(ctx, "cloud.google.com/go/firestore.DocumentRef.Update")
|
||
defer func() { trace.EndSpan(ctx, err) }()
|
||
|
||
ws, err := d.newUpdatePathWrites(updates, preconds)
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
return d.Parent.c.commit1(ctx, ws)
|
||
}
|
||
|
||
// Collections returns an iterator over the immediate sub-collections of the document.
|
||
func (d *DocumentRef) Collections(ctx context.Context) *CollectionIterator {
|
||
client := d.Parent.c
|
||
it := &CollectionIterator{
|
||
client: client,
|
||
parent: d,
|
||
it: client.c.ListCollectionIds(
|
||
withResourceHeader(ctx, client.path()),
|
||
&pb.ListCollectionIdsRequest{Parent: d.Path}),
|
||
}
|
||
it.pageInfo, it.nextFunc = iterator.NewPageInfo(
|
||
it.fetch,
|
||
func() int { return len(it.items) },
|
||
func() interface{} { b := it.items; it.items = nil; return b })
|
||
return it
|
||
}
|
||
|
||
// CollectionIterator is an iterator over sub-collections of a document.
|
||
type CollectionIterator struct {
|
||
client *Client
|
||
parent *DocumentRef
|
||
it *vkit.StringIterator
|
||
pageInfo *iterator.PageInfo
|
||
nextFunc func() error
|
||
items []*CollectionRef
|
||
err error
|
||
}
|
||
|
||
// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
|
||
func (it *CollectionIterator) PageInfo() *iterator.PageInfo { return it.pageInfo }
|
||
|
||
// Next returns the next result. Its second return value is iterator.Done if there
|
||
// are no more results. Once Next returns Done, all subsequent calls will return
|
||
// Done.
|
||
func (it *CollectionIterator) Next() (*CollectionRef, error) {
|
||
if err := it.nextFunc(); err != nil {
|
||
return nil, err
|
||
}
|
||
item := it.items[0]
|
||
it.items = it.items[1:]
|
||
return item, nil
|
||
}
|
||
|
||
func (it *CollectionIterator) fetch(pageSize int, pageToken string) (string, error) {
|
||
if it.err != nil {
|
||
return "", it.err
|
||
}
|
||
return iterFetch(pageSize, pageToken, it.it.PageInfo(), func() error {
|
||
id, err := it.it.Next()
|
||
if err != nil {
|
||
return err
|
||
}
|
||
var cr *CollectionRef
|
||
if it.parent == nil {
|
||
cr = newTopLevelCollRef(it.client, it.client.path(), id)
|
||
} else {
|
||
cr = newCollRefWithParent(it.client, it.parent, id)
|
||
}
|
||
it.items = append(it.items, cr)
|
||
return nil
|
||
})
|
||
}
|
||
|
||
// GetAll returns all the collections remaining from the iterator.
|
||
func (it *CollectionIterator) GetAll() ([]*CollectionRef, error) {
|
||
var crs []*CollectionRef
|
||
for {
|
||
cr, err := it.Next()
|
||
if err == iterator.Done {
|
||
break
|
||
}
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
crs = append(crs, cr)
|
||
}
|
||
return crs, nil
|
||
}
|
||
|
||
// Common fetch code for iterators that are backed by vkit iterators.
|
||
// TODO(jba): dedup with same function in logging/logadmin.
|
||
func iterFetch(pageSize int, pageToken string, pi *iterator.PageInfo, next func() error) (string, error) {
|
||
pi.MaxSize = pageSize
|
||
pi.Token = pageToken
|
||
// Get one item, which will fill the buffer.
|
||
if err := next(); err != nil {
|
||
return "", err
|
||
}
|
||
// Collect the rest of the buffer.
|
||
for pi.Remaining() > 0 {
|
||
if err := next(); err != nil {
|
||
return "", err
|
||
}
|
||
}
|
||
return pi.Token, nil
|
||
}
|
||
|
||
// Snapshots returns an iterator over snapshots of the document. Each time the document
|
||
// changes or is added or deleted, a new snapshot will be generated.
|
||
func (d *DocumentRef) Snapshots(ctx context.Context) *DocumentSnapshotIterator {
|
||
return &DocumentSnapshotIterator{
|
||
docref: d,
|
||
ws: newWatchStreamForDocument(ctx, d),
|
||
}
|
||
}
|
||
|
||
// DocumentSnapshotIterator is an iterator over snapshots of a document.
|
||
// Call Next on the iterator to get a snapshot of the document each time it changes.
|
||
// Call Stop on the iterator when done.
|
||
//
|
||
// For an example, see DocumentRef.Snapshots.
|
||
type DocumentSnapshotIterator struct {
|
||
docref *DocumentRef
|
||
ws *watchStream
|
||
}
|
||
|
||
// Next blocks until the document changes, then returns the DocumentSnapshot for
|
||
// the current state of the document. If the document has been deleted, Next
|
||
// returns a DocumentSnapshot whose Exists method returns false.
|
||
//
|
||
// Next never returns iterator.Done unless it is called after Stop.
|
||
func (it *DocumentSnapshotIterator) Next() (*DocumentSnapshot, error) {
|
||
btree, _, readTime, err := it.ws.nextSnapshot()
|
||
if err != nil {
|
||
if err == io.EOF {
|
||
err = iterator.Done
|
||
}
|
||
// watchStream's error is sticky, so SnapshotIterator does not need to remember it.
|
||
return nil, err
|
||
}
|
||
if btree.Len() == 0 { // document deleted
|
||
return &DocumentSnapshot{Ref: it.docref, ReadTime: readTime}, nil
|
||
}
|
||
snap, _ := btree.At(0)
|
||
return snap.(*DocumentSnapshot), nil
|
||
}
|
||
|
||
// Stop stops receiving snapshots. You should always call Stop when you are done with
|
||
// a DocumentSnapshotIterator, to free up resources. It is not safe to call Stop
|
||
// concurrently with Next.
|
||
func (it *DocumentSnapshotIterator) Stop() {
|
||
it.ws.stop()
|
||
}
|