Added support for local file storage

config/config.go

@@ -15,18 +15,25 @@ type Config struct {
 	S3 struct {
 		Bucket string
 	}
+
+	FileStorage struct {
+		Directory string
+	}
 }
 
 // Load parses arguments / ENV variable to load configuration
 func Load() *Config {
 	cfg := &Config{}
-	pflag.StringVar(&cfg.Storage, "storage", "s3", "Storage engine to use")
+	pflag.StringVar(&cfg.Storage, "storage", "s3", "Storage engine to use (s3, file)")
 	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")
 
+	// FileStorage
+	pflag.StringVar(&cfg.FileStorage.Directory, "fileDirectory", "./", "Directory to use for plain text storage")
+
 	pflag.Parse()
 	return cfg
 }

storage/adapter.go

@@ -14,23 +14,34 @@ type Storage interface {
 	Exists(dashboardID string) (bool, error)
 }
 
-// NotFoundError is a named error for more simple determination which
+// AdapterNotFoundError is a named error for more simple determination which
 // type of error is thrown
-type NotFoundError struct {
+type AdapterNotFoundError struct {
 	Name string
 }
 
-func (e NotFoundError) Error() string {
+func (e AdapterNotFoundError) Error() string {
 	return fmt.Sprintf("Storage '%s' not found.", e.Name)
 }
 
+// DashboardNotFoundError signalizes the requested dashboard could not be found
+type DashboardNotFoundError struct {
+	DashboardID string
+}
+
+func (e DashboardNotFoundError) Error() string {
+	return fmt.Sprintf("Dashboard with ID '%s' was not found.", e.DashboardID)
+}
+
 // 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
+	case "file":
+		return NewFileStorage(cfg), nil
 	}
 
-	return nil, NotFoundError{cfg.Storage}
+	return nil, AdapterNotFoundError{cfg.Storage}
 }

storage/file.go

@@ -0,0 +1,74 @@
+package storage // import "github.com/Luzifer/mondash/storage"
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+
+	"github.com/Luzifer/mondash/config"
+)
+
+// FileStorage is a storage adapter storing the data into single local files
+type FileStorage struct {
+	cfg *config.Config
+}
+
+// NewFileStorage instanciates a new FileStorage
+func NewFileStorage(cfg *config.Config) *FileStorage {
+	// Create directory if not exists
+	if _, err := os.Stat(cfg.FileStorage.Directory); os.IsNotExist(err) {
+		if err := os.MkdirAll(cfg.FileStorage.Directory, 0700); err != nil {
+			fmt.Printf("Could not create storage directory '%s'", cfg.FileStorage.Directory)
+			os.Exit(1)
+		}
+	}
+
+	return &FileStorage{
+		cfg: cfg,
+	}
+}
+
+// Put writes the given data to FS
+func (f *FileStorage) Put(dashboardID string, data []byte) error {
+	err := ioutil.WriteFile(f.getFilePath(dashboardID), data, 0600)
+
+	return err
+}
+
+// Get loads the data for the given dashboard from FS
+func (f *FileStorage) Get(dashboardID string) ([]byte, error) {
+	data, err := ioutil.ReadFile(f.getFilePath(dashboardID))
+	if err != nil {
+		return nil, DashboardNotFoundError{dashboardID}
+	}
+
+	return data, nil
+}
+
+// Delete deletes the given dashboard from FS
+func (f *FileStorage) Delete(dashboardID string) error {
+	if exists, err := f.Exists(dashboardID); err != nil || !exists {
+		if err != nil {
+			return err
+		}
+		return DashboardNotFoundError{dashboardID}
+	}
+
+	return os.Remove(f.getFilePath(dashboardID))
+}
+
+// Exists checks for the existence of the given dashboard
+func (f *FileStorage) Exists(dashboardID string) (bool, error) {
+	if _, err := os.Stat(f.getFilePath(dashboardID)); err != nil {
+		if os.IsNotExist(err) {
+			return false, nil
+		}
+		return false, err
+	}
+	return true, nil
+}
+
+func (f *FileStorage) getFilePath(dashboardID string) string {
+	return path.Join(f.cfg.FileStorage.Directory, dashboardID+".txt")
+}