backend/server: remove id and version from backend

backend/interface.go

@@ -11,10 +11,7 @@ const (
 	Lock          = "lock"
 	Snapshot      = "snapshot"
 	Index         = "index"
-)
+	Config        = "config"
-
-const (
-	Version = 1
 )
 
 // A Backend manages data stored somewhere.
@@ -43,17 +40,9 @@ type Backend interface {
 	// Close the backend
 	Close() error
 
-	Identifier
 	Lister
 }
 
-type Identifier interface {
-	// ID returns a unique ID for a specific repository. This means restic can
-	// recognize repositories accessed via different methods (e.g. local file
-	// access and sftp).
-	ID() string
-}
-
 type Lister interface {
 	// List returns a channel that yields all names of blobs of type t in
 	// lexicographic order. A goroutine is started for this. If the channel

backend/local/local.go

@@ -1,9 +1,6 @@
 package local
 
 import (
-	"crypto/rand"
-	"crypto/sha256"
-	"encoding/hex"
 	"errors"
 	"fmt"
 	"io"
@@ -11,7 +8,6 @@ import (
 	"os"
 	"path/filepath"
 	"sort"
-	"strings"
 
 	"github.com/restic/restic/backend"
 )
@@ -20,8 +16,6 @@ var ErrWrongData = errors.New("wrong data returned by backend, checksum does not
 
 type Local struct {
 	p string
-	ver uint
-	id  string
 }
 
 // Open opens the local backend at dir.
@@ -36,68 +30,19 @@ func Open(dir string) (*Local, error) {
 		filepath.Join(dir, backend.Paths.Temp),
 	}
 
-	// test if all necessary dirs and files are there
+	// test if all necessary dirs are there
 	for _, d := range items {
 		if _, err := os.Stat(d); err != nil {
 			return nil, fmt.Errorf("%s does not exist", d)
 		}
 	}
 
-	// read version file
+	return &Local{p: dir}, nil
-	f, err := os.Open(filepath.Join(dir, backend.Paths.Version))
-	if err != nil {
-		return nil, fmt.Errorf("unable to read version file: %v\n", err)
-	}
-
-	var version uint
-	n, err := fmt.Fscanf(f, "%d", &version)
-	if err != nil {
-		return nil, err
-	}
-
-	if n != 1 {
-		return nil, errors.New("could not read version from file")
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	// check version
-	if version != backend.Version {
-		return nil, fmt.Errorf("wrong version %d", version)
-	}
-
-	// read ID
-	f, err = os.Open(filepath.Join(dir, backend.Paths.ID))
-	if err != nil {
-		return nil, err
-	}
-
-	buf, err := ioutil.ReadAll(f)
-	if err != nil {
-		return nil, err
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	id := strings.TrimSpace(string(buf))
-	if err != nil {
-		return nil, err
-	}
-
-	return &Local{p: dir, ver: version, id: id}, nil
 }
 
 // Create creates all the necessary files and directories for a new local
-// backend at dir.
+// backend at dir. Afterwards a new config blob should must created.
 func Create(dir string) (*Local, error) {
-	versionFile := filepath.Join(dir, backend.Paths.Version)
-	idFile := filepath.Join(dir, backend.Paths.ID)
 	dirs := []string{
 		dir,
 		filepath.Join(dir, backend.Paths.Data),
@@ -108,15 +53,10 @@ func Create(dir string) (*Local, error) {
 		filepath.Join(dir, backend.Paths.Temp),
 	}
 
-	// test if files already exist
+	// test if config file already exist
-	_, err := os.Lstat(versionFile)
+	_, err := os.Lstat(backend.Paths.Config)
 	if err == nil {
-		return nil, errors.New("version file already exists")
+		return nil, errors.New("config file already exists")
-	}
-
-	_, err = os.Lstat(idFile)
-	if err == nil {
-		return nil, errors.New("id file already exists")
 	}
 
 	// test if directories already exist
@@ -134,44 +74,6 @@ func Create(dir string) (*Local, error) {
 		}
 	}
 
-	// create version file
-	f, err := os.Create(versionFile)
-	if err != nil {
-		return nil, err
-	}
-
-	_, err = fmt.Fprintf(f, "%d\n", backend.Version)
-	if err != nil {
-		return nil, err
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	// create ID file
-	id := make([]byte, sha256.Size)
-	_, err = rand.Read(id)
-	if err != nil {
-		return nil, err
-	}
-
-	f, err = os.Create(idFile)
-	if err != nil {
-		return nil, err
-	}
-
-	_, err = fmt.Fprintln(f, hex.EncodeToString(id))
-	if err != nil {
-		return nil, err
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
 	// open backend
 	return Open(dir)
 }
@@ -265,6 +167,10 @@ func (b *Local) Create() (backend.Blob, error) {
 
 // Construct path for given Type and name.
 func filename(base string, t backend.Type, name string) string {
+	if t == backend.Config {
+		return filepath.Join(base, "config")
+	}
+
 	return filepath.Join(dirname(base, t, name), name)
 }
 
@@ -376,16 +282,6 @@ func (b *Local) List(t backend.Type, done <-chan struct{}) <-chan string {
 	return ch
 }
 
-// Version returns the version of this local backend.
-func (b *Local) Version() uint {
-	return b.ver
-}
-
-// ID returns the ID of this local backend.
-func (b *Local) ID() string {
-	return b.id
-}
-
 // Delete removes the repository and all files.
 func (b *Local) Delete() error { return os.RemoveAll(b.p) }
 

backend/paths.go

@@ -10,8 +10,7 @@ var Paths = struct {
 	Locks     string
 	Keys      string
 	Temp      string
-	Version   string
+	Config    string
-	ID        string
 }{
 	"data",
 	"snapshots",
@@ -19,8 +18,7 @@ var Paths = struct {
 	"locks",
 	"keys",
 	"tmp",
-	"version",
+	"config",
-	"id",
 }
 
 // Default modes for file-based backends

backend/sftp/sftp.go

@@ -2,18 +2,15 @@ package sftp
 
 import (
 	"crypto/rand"
-	"crypto/sha256"
 	"encoding/hex"
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"sort"
-	"strings"
 
 	"github.com/pkg/sftp"
 	"github.com/restic/restic/backend"
@@ -26,8 +23,6 @@ const (
 type SFTP struct {
 	c *sftp.Client
 	p string
-	ver uint
-	id  string
 
 	cmd *exec.Cmd
 }
@@ -81,8 +76,7 @@ func Open(dir string, program string, args ...string) (*SFTP, error) {
 		filepath.Join(dir, backend.Paths.Index),
 		filepath.Join(dir, backend.Paths.Locks),
 		filepath.Join(dir, backend.Paths.Keys),
-		filepath.Join(dir, backend.Paths.Version),
+		filepath.Join(dir, backend.Paths.Temp),
-		filepath.Join(dir, backend.Paths.ID),
 	}
 	for _, d := range items {
 		if _, err := sftp.c.Lstat(d); err != nil {
@@ -90,64 +84,18 @@ func Open(dir string, program string, args ...string) (*SFTP, error) {
 		}
 	}
 
-	// read version file
-	f, err := sftp.c.Open(filepath.Join(dir, backend.Paths.Version))
-	if err != nil {
-		return nil, fmt.Errorf("unable to read version file: %v\n", err)
-	}
-
-	var version uint
-	n, err := fmt.Fscanf(f, "%d", &version)
-	if err != nil {
-		return nil, err
-	}
-
-	if n != 1 {
-		return nil, errors.New("could not read version from file")
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	// check version
-	if version != backend.Version {
-		return nil, fmt.Errorf("wrong version %d", version)
-	}
-
-	// read ID
-	f, err = sftp.c.Open(filepath.Join(dir, backend.Paths.ID))
-	if err != nil {
-		return nil, err
-	}
-
-	buf, err := ioutil.ReadAll(f)
-	if err != nil {
-		return nil, err
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	sftp.id = strings.TrimSpace(string(buf))
 	sftp.p = dir
-
 	return sftp, nil
 }
 
 // Create creates all the necessary files and directories for a new sftp
-// backend at dir.
+// backend at dir. Afterwards a new config blob should must created.
 func Create(dir string, program string, args ...string) (*SFTP, error) {
 	sftp, err := startClient(program, args...)
 	if err != nil {
 		return nil, err
 	}
 
-	versionFile := filepath.Join(dir, backend.Paths.Version)
-	idFile := filepath.Join(dir, backend.Paths.ID)
 	dirs := []string{
 		dir,
 		filepath.Join(dir, backend.Paths.Data),
@@ -158,15 +106,10 @@ func Create(dir string, program string, args ...string) (*SFTP, error) {
 		filepath.Join(dir, backend.Paths.Temp),
 	}
 
-	// test if files already exist
+	// test if config file already exist
-	_, err = sftp.c.Lstat(versionFile)
+	_, err = sftp.c.Lstat(backend.Paths.Config)
 	if err == nil {
-		return nil, errors.New("version file already exists")
+		return nil, errors.New("config file already exists")
-	}
-
-	_, err = sftp.c.Lstat(idFile)
-	if err == nil {
-		return nil, errors.New("id file already exists")
 	}
 
 	// test if directories already exist
@@ -184,44 +127,6 @@ func Create(dir string, program string, args ...string) (*SFTP, error) {
 		}
 	}
 
-	// create version file
-	f, err := sftp.c.Create(versionFile)
-	if err != nil {
-		return nil, err
-	}
-
-	_, err = fmt.Fprintf(f, "%d\n", backend.Version)
-	if err != nil {
-		return nil, err
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	// create ID file
-	id := make([]byte, sha256.Size)
-	_, err = rand.Read(id)
-	if err != nil {
-		return nil, err
-	}
-
-	f, err = sftp.c.Create(idFile)
-	if err != nil {
-		return nil, err
-	}
-
-	_, err = fmt.Fprintln(f, hex.EncodeToString(id))
-	if err != nil {
-		return nil, err
-	}
-
-	err = f.Close()
-	if err != nil {
-		return nil, err
-	}
-
 	err = sftp.c.Close()
 	if err != nil {
 		return nil, err
@@ -389,6 +294,10 @@ func (r *SFTP) Create() (backend.Blob, error) {
 
 // Construct path for given backend.Type and name.
 func (r *SFTP) filename(t backend.Type, name string) string {
+	if t == backend.Config {
+		return filepath.Join(r.p, "config")
+	}
+
 	return filepath.Join(r.dirname(t, name), name)
 }
 
@@ -542,16 +451,6 @@ func (r *SFTP) List(t backend.Type, done <-chan struct{}) <-chan string {
 
 }
 
-// Version returns the version of this local backend.
-func (r *SFTP) Version() uint {
-	return r.ver
-}
-
-// ID returns the ID of this local backend.
-func (r *SFTP) ID() string {
-	return r.id
-}
-
 // Close closes the sftp connection and terminates the underlying command.
 func (s *SFTP) Close() error {
 	if s == nil {

cache.go

@@ -18,13 +18,13 @@ type Cache struct {
 	base string
 }
 
-func NewCache(be backend.Identifier) (*Cache, error) {
+func NewCache(s *server.Server) (*Cache, error) {
 	cacheDir, err := getCacheDir()
 	if err != nil {
 		return nil, err
 	}
 
-	basedir := filepath.Join(cacheDir, be.ID())
+	basedir := filepath.Join(cacheDir, s.ID())
 	debug.Log("Cache.New", "opened cache at %v", basedir)
 
 	return &Cache{base: basedir}, nil

server/server.go

@@ -601,7 +601,7 @@ func (s *Server) Delete() error {
 }
 
 func (s *Server) ID() string {
-	return s.be.ID()
+	return "empty"
 }
 
 func (s *Server) Location() string {