fix: no db error when db size is 0 (#629)

Fixes the error where File Browser would fail when the DB existed with size 0. This closes #628.

@1138-4EB I decided not to check the version for now since it's the first time we're adding that info. Only the next time we change the DB structure we'll use that value as reference to know how to upgrade.

I did not check it because the users running rc1 would have some issues with it.

Former-commit-id: e8b07ab919e9c24feee8f6f2dd6df30df1e2325f [formerly 3396f05b4a1a07e1b993b7c07d1afd2def9cabbb] [formerly b43eb8e400603f99baf7966a58156dec7bd47420 [formerly c1c57c6525]]
Former-commit-id: 1115d0cf8a601feafac2b33cb46b813343f4fa8c [formerly 05de6caf8cf747a95fbb10587f0a767dfb8b8774]
Former-commit-id: 840c1a278cd45d36ce8538b7c5fe97923be05ca3

cmd/utils.go

@@ -62,29 +62,43 @@ type pythonData struct {
 	store *storage.Storage
 }
 
+func dbExists(path string) (bool, error) {
+	stat, err := os.Stat(path)
+
+	if os.IsNotExist(err) {
+		return false, nil
+	} else if err != nil {
+		return false, err
+	}
+
+	if stat.Size() == 0 {
+		return false, nil
+	}
+
+	return true, nil
+}
+
 func python(fn pythonFunc, cfg pythonConfig) cobraFunc {
 	return func(cmd *cobra.Command, args []string) {
 		data := pythonData{hadDB: true}
 
 		path := getParam(cmd.Flags(), "database")
-		_, err := os.Stat(path)
+		exists, err := dbExists(path)
 
-		if os.IsNotExist(err) {
-			data.hadDB = false
-
-			if !cfg.noDB && !cfg.allowNoDB {
-				log.Fatal(path + " does not exist. Please run 'filebrowser config init' first.")
-			}
-		} else if err != nil {
+		if err != nil {
 			panic(err)
-		} else if err == nil && cfg.noDB {
+		} else if exists && cfg.noDB {
 			log.Fatal(path + " already exists")
+		} else if !exists && !cfg.noDB && !cfg.allowNoDB {
+			log.Fatal(path + " does not exist. Please run 'filebrowser config init' first.")
 		}
 
+		data.hadDB = exists
 		db, err := storm.Open(path)
 		checkErr(err)
 		defer db.Close()
-		data.store = bolt.NewStorage(db)
+		data.store, err = bolt.NewStorage(db)
+		checkErr(err)
 		fn(cmd, args, data)
 	}
 }

storage/bolt/bolt.go

@@ -10,16 +10,21 @@ import (
 )
 
 // NewStorage creates a storage.Storage based on Bolt DB.
-func NewStorage(db *storm.DB) *storage.Storage {
+func NewStorage(db *storm.DB) (*storage.Storage, error) {
 	users := users.NewStorage(usersBackend{db: db})
 	share := share.NewStorage(shareBackend{db: db})
 	settings := settings.NewStorage(settingsBackend{db: db})
 	auth := auth.NewStorage(authBackend{db: db}, users)
 
+	err := save(db, "version", 2)
+	if err != nil {
+		return nil, err
+	}
+
 	return &storage.Storage{
 		Auth:     auth,
 		Users:    users,
 		Share:    share,
 		Settings: settings,
-	}
+	}, nil
 }

storage/bolt/importer/importer.go

@@ -19,7 +19,10 @@ func Import(oldDB, oldConf, newDB string) error {
 	}
 	defer new.Close()
 
-	sto := bolt.NewStorage(new)
+	sto, err := bolt.NewStorage(new)
+	if err != nil {
+		return err
+	}
 
 	err = importUsers(old, sto)
 	if err != nil {