Test if a config file on open

src/cmds/restic/global.go

@@ -402,6 +402,16 @@ func open(s string, opts options.Options) (restic.Backend, error) {
 		return nil, errors.Fatalf("unable to open repo at %v: %v", s, err)
 	}
 
+	// check if config is there
+	fi, err := be.Stat(restic.Handle{Type: restic.ConfigFile})
+	if err != nil {
+		return nil, errors.Fatalf("unable to open config file: %v\nIs there a repository at the following location?\n%v", err, s)
+	}
+
+	if fi.Size == 0 {
+		return nil, errors.New("config file has zero size, invalid repository?")
+	}
+
 	return be, nil
 }
 

src/restic/backend/local/local.go

@@ -34,13 +34,6 @@ func Open(cfg Config) (*Local, error) {
 
 	be := &Local{Config: cfg, Layout: l}
 
-	// test if all necessary dirs are there
-	for _, d := range be.Paths() {
-		if _, err := fs.Stat(d); err != nil {
-			return nil, errors.Wrap(err, "Open")
-		}
-	}
-
 	return be, nil
 }
 
@@ -65,7 +58,7 @@ func Create(cfg Config) (*Local, error) {
 		return nil, errors.New("config file already exists")
 	}
 
-	// create paths for data, refs and temp
+	// create paths for data and refs
 	for _, d := range be.Paths() {
 		err := fs.MkdirAll(d, backend.Modes.Dir)
 		if err != nil {

src/restic/backend/sftp/sftp.go

@@ -124,13 +124,6 @@ func Open(cfg Config) (*SFTP, error) {
 		return nil, err
 	}
 
-	// test if all necessary dirs and files are there
-	for _, d := range sftp.Paths() {
-		if _, err := sftp.c.Lstat(d); err != nil {
-			return nil, errors.Errorf("%s does not exist", d)
-		}
-	}
-
 	debug.Log("layout: %v\n", sftp.Layout)
 
 	sftp.Config = cfg
@@ -204,7 +197,7 @@ func Create(cfg Config) (*SFTP, error) {
 		return nil, errors.New("config file already exists")
 	}
 
-	// create paths for data, refs and temp blobs
+	// create paths for data and refs
 	for _, d := range sftp.Paths() {
 		err = sftp.mkdirAll(d, backend.Modes.Dir)
 		debug.Log("mkdirAll %v -> %v", d, err)