Add support for --prefix and --strip-components options on backup com…

…mand.

cmd/restic/cmd_backup.go

@@ -76,6 +76,8 @@ type BackupOptions struct {
 	FilesFrom        string
 	TimeStamp        string
 	WithAtime        bool
+	RootPrefix       string
+	RootStrip        int
 }
 
 var backupOptions BackupOptions
@@ -98,6 +100,8 @@ func init() {
 	f.StringVar(&backupOptions.FilesFrom, "files-from", "", "read the files to backup from file (can be combined with file args)")
 	f.StringVar(&backupOptions.TimeStamp, "time", "", "time of the backup (ex. '2012-11-01 22:08:41') (default: now)")
 	f.BoolVar(&backupOptions.WithAtime, "with-atime", false, "store the atime for all files and directories")
+	f.StringVar(&backupOptions.RootPrefix, "prefix", "", "apply a prefix to target paths")
+	f.IntVar(&backupOptions.RootStrip, "strip-components", 0, "strip NUMBER leading components from target paths")
 }
 
 // filterExisting returns a slice of all existing items, or an error if no
@@ -484,6 +488,8 @@ func runBackup(opts BackupOptions, gopts GlobalOptions, term *termstatus.Termina
 		Time:           timeStamp,
 		Hostname:       opts.Hostname,
 		ParentSnapshot: *parentSnapshotID,
+		RootPrefix:     opts.RootPrefix,
+		RootStrip:      opts.RootStrip,
 	}
 
 	uploader := archiver.IndexUploader{

internal/archiver/archiver.go

@@ -705,6 +705,8 @@ type SnapshotOptions struct {
 	Excludes       []string
 	Time           time.Time
 	ParentSnapshot restic.ID
+	RootPrefix     string
+	RootStrip      int
 }
 
 // loadParentTree loads a tree referenced by snapshot id. If id is null, nil is returned.
@@ -807,7 +809,7 @@ func (arch *Archiver) Snapshot(ctx context.Context, targets []string, opts Snaps
 		return nil, restic.ID{}, err
 	}
 
-	sn, err := restic.NewSnapshot(targets, opts.Tags, opts.Hostname, opts.Time)
+	sn, err := restic.NewSnapshot(targets, opts.Tags, opts.Hostname, opts.Time, opts.RootPrefix, opts.RootStrip)
 	sn.Excludes = opts.Excludes
 	if !opts.ParentSnapshot.IsNull() {
 		id := opts.ParentSnapshot

internal/restic/snapshot.go

@@ -27,17 +27,42 @@ type Snapshot struct {
 	id *ID // plaintext ID, used during restore
 }
 
+func pathSplit(path string) (root string, lst []string) {
+	for root = filepath.Clean(path); ; {
+		var file string
+		root, file = filepath.Split(root)
+		if file == "" {
+			break
+		}
+		lst = append([]string{file}, lst...)
+	}
+	return
+}
+
 // NewSnapshot returns an initialized snapshot struct for the current user and
 // time.
-func NewSnapshot(paths []string, tags []string, hostname string, time time.Time) (*Snapshot, error) {
+func NewSnapshot(paths []string, tags []string, hostname string, time time.Time, prefix string, strip int) (*Snapshot, error) {
 	absPaths := make([]string, 0, len(paths))
 	for _, path := range paths {
-		p, err := filepath.Abs(path)
-		if err == nil {
-			absPaths = append(absPaths, p)
+		pathRoot, pathList := pathSplit(path)
+		if strip > 0 {
+			var stripRoot int
+			if pathRoot != "" {
+				stripRoot++
+			}
+			pathList = pathList[strip-stripRoot:]
+			pathRoot = ""
+		}
+		if prefix != "" {
+			pathRoot = prefix
 		} else {
-			absPaths = append(absPaths, path)
+			absPath, err := filepath.Abs(pathRoot)
+			if err == nil {
+				pathRoot = absPath
+			}
 		}
+		p := filepath.Join(append([]string{pathRoot}, pathList...)...)
+		absPaths = append(absPaths, p)
 	}
 
 	sn := &Snapshot{

internal/restic/snapshot_test.go

@@ -11,6 +11,6 @@ import (
 func TestNewSnapshot(t *testing.T) {
 	paths := []string{"/home/foobar"}
 
-	_, err := restic.NewSnapshot(paths, nil, "foo", time.Now())
+	_, err := restic.NewSnapshot(paths, nil, "foo", time.Now(), "", 0)
 	rtest.OK(t, err)
 }

internal/restic/testing.go

@@ -164,7 +164,7 @@ func TestCreateSnapshot(t testing.TB, repo Repository, at time.Time, depth int,
 	t.Logf("create fake snapshot at %s with seed %d", at, seed)
 
 	fakedir := fmt.Sprintf("fakedir-at-%v", at.Format("2006-01-02 15:04:05"))
-	snapshot, err := NewSnapshot([]string{fakedir}, []string{"test"}, "foo", time.Now())
+	snapshot, err := NewSnapshot([]string{fakedir}, []string{"test"}, "foo", time.Now(), "", 0)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/restorer/restorer_test.go

@@ -107,7 +107,7 @@ func saveSnapshot(t testing.TB, repo restic.Repository, snapshot Snapshot) (*res
 		t.Fatal(err)
 	}
 
-	sn, err := restic.NewSnapshot([]string{"test"}, nil, "", time.Now())
+	sn, err := restic.NewSnapshot([]string{"test"}, nil, "", time.Now(), "", 0)
 	if err != nil {
 		t.Fatal(err)
 	}