Moved towards modular storage system

config/config.go

@@ -0,0 +1,30 @@
+package config // import "github.com/Luzifer/mondash/config"
+
+import (
+	"os"
+
+	"github.com/spf13/pflag"
+)
+
+type Config struct {
+	Storage  string
+	BaseURL  string
+	APIToken string
+
+	S3 struct {
+		Bucket string
+	}
+}
+
+func Load() *Config {
+	cfg := &Config{}
+	pflag.StringVar(&cfg.Storage, "storage", "s3", "Storage engine to use")
+	pflag.StringVar(&cfg.BaseURL, "baseurl", os.Getenv("BASE_URL"), "The Base-URL the application is running on for example https://mondash.org")
+	pflag.StringVar(&cfg.APIToken, "api-token", os.Getenv("API_TOKEN"), "API Token used for the /welcome dashboard (you can choose your own)")
+
+	// S3
+	pflag.StringVar(&cfg.S3.Bucket, "s3Bucket", os.Getenv("S3Bucket"), "Bucket to use for S3 storage")
+
+	pflag.Parse()
+	return cfg
+}

main.go

@@ -5,33 +5,31 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net/http"
-	"os"
 	"time"
 
-	"log"
-
-	"launchpad.net/goamz/aws"
-	"launchpad.net/goamz/s3"
-
+	"github.com/Luzifer/mondash/config"
+	"github.com/Luzifer/mondash/storage"
 	"github.com/flosch/pongo2"
 	"github.com/go-martini/martini"
 
 	_ "github.com/flosch/pongo2-addons"
 )
 
-var templates = make(map[string]*pongo2.Template)
-var s3Storage *s3.Bucket
+var (
+	templates = make(map[string]*pongo2.Template)
+	store     storage.Storage
+	cfg       *config.Config
+)
 
 func main() {
 	preloadTemplates()
 
-	// Initialize S3 storage
-	awsAuth, err := aws.EnvAuth()
+	var err error
+	cfg = config.Load()
+	store, err = storage.GetStorage(cfg)
 	if err != nil {
-		log.Fatal(err)
+		fmt.Printf("An error occurred while loading the storage handler: %s", err)
 	}
-	s3Conn := s3.New(awsAuth, aws.EUWest)
-	s3Storage = s3Conn.Bucket(os.Getenv("S3Bucket"))
 
 	m := martini.Classic()
 
@@ -48,7 +46,7 @@ func main() {
 	m.Delete("/:dashid", handleDeleteDashboard)
 	m.Delete("/:dashid/:metricid", handleDeleteMetric)
 
-	go runWelcomePage()
+	go runWelcomePage(cfg)
 
 	// GO!
 	m.Run()

storage/adapter.go

@@ -0,0 +1,36 @@
+package storage // import "github.com/Luzifer/mondash/storage"
+
+import (
+	"fmt"
+
+	"github.com/Luzifer/mondash/config"
+)
+
+// Storage is an interface to have all storage systems compatible to each other
+type Storage interface {
+	Put(dashboardID string, data []byte) error
+	Get(dashboardID string) ([]byte, error)
+	Delete(dashboardID string) error
+	Exists(dashboardID string) (bool, error)
+}
+
+// NotFoundError is a named error for more simple determination which
+// type of error is thrown
+type NotFoundError struct {
+	Name string
+}
+
+func (e NotFoundError) Error() string {
+	return fmt.Sprintf("Storage '%s' not found.", e.Name)
+}
+
+// GetStorage acts as a storage factory providing the storage named by input
+// name parameter
+func GetStorage(cfg *config.Config) (Storage, error) {
+	switch cfg.Storage {
+	case "s3":
+		return NewS3Storage(cfg), nil
+	}
+
+	return nil, NotFoundError{cfg.Storage}
+}

storage/s3.go

@@ -0,0 +1,82 @@
+package storage // import "github.com/Luzifer/mondash/storage"
+
+import (
+	"io/ioutil"
+	"strings"
+
+	"github.com/Luzifer/mondash/config"
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/service/s3"
+)
+
+type S3Storage struct {
+	s3connection *s3.S3
+	cfg          *config.Config
+}
+
+func NewS3Storage(cfg *config.Config) *S3Storage {
+	s3connection := s3.New(&aws.Config{})
+	return &S3Storage{
+		s3connection: s3connection,
+	}
+}
+
+func (s *S3Storage) Put(dashboardID string, data []byte) error {
+	_, err := s.s3connection.PutObject(&s3.PutObjectInput{
+		Bucket:      aws.String(s.cfg.S3.Bucket),
+		ContentType: aws.String("application/json"),
+		Key:         aws.String(dashboardID),
+		// TODO: Private ACL
+	})
+
+	return err
+}
+
+func (s *S3Storage) Get(dashboardID string) ([]byte, error) {
+	res, err := s.s3connection.GetObject(&s3.GetObjectInput{
+		Bucket: aws.String(s.cfg.S3.Bucket),
+		Key:    aws.String(dashboardID),
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	defer res.Body.Close()
+
+	data, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	return data, nil
+}
+
+func (s *S3Storage) Delete(dashboardID string) error {
+	_, err := s.s3connection.DeleteObject(&s3.DeleteObjectInput{
+		Bucket: aws.String(s.cfg.S3.Bucket),
+		Key:    aws.String(dashboardID),
+	})
+
+	return err
+}
+
+func (s *S3Storage) Exists(dashboardID string) (bool, error) {
+	_, err := s.s3connection.HeadObject(&s3.HeadObjectInput{
+		Bucket: aws.String(s.cfg.S3.Bucket),
+		Key:    aws.String(dashboardID),
+	})
+
+	if err != nil {
+		if awsErr, ok := err.(awserr.Error); ok {
+			if strings.Contains(awsErr.Error(), "status code: 404") {
+				return false, nil
+			}
+			return false, err
+		} else {
+			return false, err
+		}
+	}
+
+	return true, nil
+}

structs.go

@@ -3,26 +3,31 @@ package main
 import (
 	"encoding/json"
 	"errors"
-	"launchpad.net/goamz/s3"
 	"log"
 	"sort"
 	"strconv"
 	"time"
+
+	"github.com/Luzifer/mondash/storage"
 )
 
 type dashboard struct {
 	DashboardID string           `json:"-"`
 	APIKey      string           `json:"api_key"`
 	Metrics     dashboardMetrics `json:"metrics"`
+	storage     storage.Storage
 }
 
-func loadDashboard(dashid string) (*dashboard, error) {
-	data, err := s3Storage.Get(dashid)
+func loadDashboard(dashid string, store storage.Storage) (*dashboard, error) {
+	data, err := store.Get(dashid)
 	if err != nil {
 		return &dashboard{}, errors.New("Dashboard not found")
 	}
 
-	tmp := &dashboard{DashboardID: dashid}
+	tmp := &dashboard{
+		DashboardID: dashid,
+		storage:     store,
+	}
 	_ = json.Unmarshal(data, tmp)
 
 	return tmp, nil
@@ -34,7 +39,7 @@ func (d *dashboard) Save() {
 		log.Printf("Error while marshalling dashboard: %s", err)
 		return
 	}
-	err = s3Storage.Put(d.DashboardID, data, "application/json", s3.Private)
+	err = d.storage.Put(d.DashboardID, data)
 	if err != nil {
 		log.Printf("Error while storing dashboard: %s", err)
 	}

web_handlers.go

@@ -18,17 +18,18 @@ func handleRedirectWelcome(res http.ResponseWriter, req *http.Request) {
 }
 
 func handleCreateRandomDashboard(res http.ResponseWriter, req *http.Request) {
-	urlProposal := generateAPIKey()[0:20]
-	_, err := s3Storage.Get(urlProposal)
-	for err == nil {
+	var urlProposal string
+	for {
 		urlProposal = generateAPIKey()[0:20]
-		_, err = s3Storage.Get(urlProposal)
+		if exists, err := store.Exists(urlProposal); err == nil && !exists {
+			break
+		}
 	}
 	http.Redirect(res, req, fmt.Sprintf("/%s", urlProposal), http.StatusTemporaryRedirect)
 }
 
 func handleDisplayDashboard(params martini.Params, res http.ResponseWriter) {
-	dash, err := loadDashboard(params["dashid"])
+	dash, err := loadDashboard(params["dashid"], store)
 	if err != nil {
 		dash = &dashboard{APIKey: generateAPIKey(), Metrics: dashboardMetrics{}}
 	}
@@ -51,7 +52,7 @@ func handleDisplayDashboard(params martini.Params, res http.ResponseWriter) {
 }
 
 func handleDeleteDashboard(params martini.Params, req *http.Request, res http.ResponseWriter) {
-	dash, err := loadDashboard(params["dashid"])
+	dash, err := loadDashboard(params["dashid"], store)
 	if err != nil {
 		http.Error(res, "This dashboard does not exist.", http.StatusInternalServerError)
 		return
@@ -62,7 +63,7 @@ func handleDeleteDashboard(params martini.Params, req *http.Request, res http.Re
 		return
 	}
 
-	_ = s3Storage.Del(params["dashid"])
+	store.Delete(params["dashid"])
 	http.Error(res, "OK", http.StatusOK)
 }
 
@@ -80,7 +81,7 @@ func handlePutMetric(params martini.Params, req *http.Request, res http.Response
 		return
 	}
 
-	dash, err := loadDashboard(params["dashid"])
+	dash, err := loadDashboard(params["dashid"], store)
 	if err != nil {
 		if len(req.Header.Get("Authorization")) < 10 {
 			http.Error(res, "APIKey is too insecure", http.StatusUnauthorized)
@@ -122,7 +123,7 @@ func handlePutMetric(params martini.Params, req *http.Request, res http.Response
 }
 
 func handleDeleteMetric(params martini.Params, req *http.Request, res http.ResponseWriter) {
-	dash, err := loadDashboard(params["dashid"])
+	dash, err := loadDashboard(params["dashid"], store)
 	if err != nil {
 		dash = &dashboard{APIKey: req.Header.Get("Authorization"), Metrics: dashboardMetrics{}, DashboardID: params["dashid"]}
 	}

welcome_runner.go

@@ -7,13 +7,14 @@ import (
 	"log"
 	"math/rand"
 	"net/http"
-	"os"
 	"time"
+
+	"github.com/Luzifer/mondash/config"
 )
 
-func runWelcomePage() {
-	baseURL := os.Getenv("BASE_URL")
-	welcomeAPIToken := os.Getenv("API_TOKEN")
+func runWelcomePage(cfg *config.Config) {
+	baseURL := cfg.BaseURL
+	welcomeAPIToken := cfg.APIToken
 	generateTicker := time.NewTicker(time.Minute)
 
 	for {