copy,move: restore --no-traverse flag

The --no-traverse flag was not implemented when the new sync routines
(using the march package) was implemented.

This re-implements --no-traverse in march by trying to find a match
for each object with NewObject rather than from a directory listing.

cmd/copy/copy.go

@@ -51,6 +51,17 @@ written a trailing / - meaning "copy the contents of this directory".
 This applies to all commands and whether you are talking about the
 source or destination.
 
+See the [--no-traverse](/docs/#no-traverse) option for controlling
+whether rclone lists the destination directory or not.  Supplying this
+option when copying a small number of files into a large destination
+can speed transfers up greatly.
+
+For example, if you have many files in /path/to/src but only a few of
+them change every day, you can to copy all the files which have
+changed recently very efficiently like this:
+
+    rclone copy --max-age 24h --no-traverse /path/to/src remote:
+
 **Note**: Use the ` + "`-P`" + `/` + "`--progress`" + ` flag to view real-time transfer statistics
 `,
 	Run: func(command *cobra.Command, args []string) {

cmd/move/move.go

@@ -37,6 +37,11 @@ into ` + "`dest:path`" + ` then delete the original (if no errors on copy) in
 
 If you want to delete empty source directories after move, use the --delete-empty-src-dirs flag.
 
+See the [--no-traverse](/docs/#no-traverse) option for controlling
+whether rclone lists the destination directory or not.  Supplying this
+option when moving a small number of files into a large destination
+can speed transfers up greatly.
+
 **Important**: Since this can cause data loss, test first with the
 --dry-run flag.
 

docs/content/docs.md

@@ -842,8 +842,8 @@ will fall back to the default behaviour and log an error level message
 to the console. Note: Encrypted destinations are not supported
 by `--track-renames`.
 
-Note that `--track-renames` uses extra memory to keep track of all
-the rename candidates.
+Note that `--track-renames` is incompatible with `--no-traverse` and
+that it uses extra memory to keep track of all the rename candidates.
 
 Note also that `--track-renames` is incompatible with
 `--delete-before` and will select `--delete-after` instead of
@@ -1132,6 +1132,24 @@ This option defaults to `false`.
 
 **This should be used only for testing.**
 
+### --no-traverse ###
+
+The `--no-traverse` flag controls whether the destination file system
+is traversed when using the `copy` or `move` commands.
+`--no-traverse` is not compatible with `sync` and will be ignored if
+you supply it with `sync`.
+
+If you are only copying a small number of files (or are filtering most
+of the files) and/or have a large number of files on the destination
+then `--no-traverse` will stop rclone listing the destination and save
+time.
+
+However, if you are copying a large number of files, especially if you
+are doing a copy where lots of the files under consideration haven't
+changed and won't need copying then you shouldn't use `--no-traverse`.
+
+See [rclone copy](/commands/rclone_copy/) for an example of how to use it.
+
 Filtering
 ---------
 

fs/config.go

@@ -62,6 +62,7 @@ type ConfigInfo struct {
 	MaxDepth              int
 	IgnoreSize            bool
 	IgnoreChecksum        bool
+	NoTraverse            bool
 	NoUpdateModTime       bool
 	DataRateUnit          string
 	BackupDir             string

fs/config/configflags/configflags.go

@@ -27,7 +27,6 @@ var (
 	deleteAfter     bool
 	bindAddr        string
 	disableFeatures string
-	noTraverse      bool
 )
 
 // AddFlags adds the non filing system specific flags to the command
@@ -65,7 +64,7 @@ func AddFlags(flagSet *pflag.FlagSet) {
 	flags.IntVarP(flagSet, &fs.Config.MaxDepth, "max-depth", "", fs.Config.MaxDepth, "If set limits the recursion depth to this.")
 	flags.BoolVarP(flagSet, &fs.Config.IgnoreSize, "ignore-size", "", false, "Ignore size when skipping use mod-time or checksum.")
 	flags.BoolVarP(flagSet, &fs.Config.IgnoreChecksum, "ignore-checksum", "", fs.Config.IgnoreChecksum, "Skip post copy check of checksums.")
-	flags.BoolVarP(flagSet, &noTraverse, "no-traverse", "", noTraverse, "Obsolete - does nothing.")
+	flags.BoolVarP(flagSet, &fs.Config.NoTraverse, "no-traverse", "", fs.Config.NoTraverse, "Don't traverse destination file system on copy.")
 	flags.BoolVarP(flagSet, &fs.Config.NoUpdateModTime, "no-update-modtime", "", fs.Config.NoUpdateModTime, "Don't update destination mod-time if files identical.")
 	flags.StringVarP(flagSet, &fs.Config.BackupDir, "backup-dir", "", fs.Config.BackupDir, "Make backups into hierarchy based in DIR.")
 	flags.StringVarP(flagSet, &fs.Config.Suffix, "suffix", "", fs.Config.Suffix, "Suffix for use with --backup-dir.")
@@ -113,10 +112,6 @@ func SetFlags() {
 		}
 	}
 
-	if noTraverse {
-		fs.Logf(nil, "--no-traverse is obsolete and no longer needed - please remove")
-	}
-
 	if dumpHeaders {
 		fs.Config.Dump |= fs.DumpHeaders
 		fs.Logf(nil, "--dump-headers is obsolete - please use --dump headers instead")

fs/march/march.go

@@ -23,6 +23,7 @@ type March struct {
 	Fdst          fs.Fs           // source Fs
 	Fsrc          fs.Fs           // dest Fs
 	Dir           string          // directory
+	NoTraverse    bool            // don't traverse the destination
 	SrcIncludeAll bool            // don't include all files in the src
 	DstIncludeAll bool            // don't include all files in the destination
 	Callback      Marcher         // object to call with results
@@ -45,7 +46,9 @@ type Marcher interface {
 // init sets up a march over opt.Fsrc, and opt.Fdst calling back callback for each match
 func (m *March) init() {
 	m.srcListDir = m.makeListDir(m.Fsrc, m.SrcIncludeAll)
-	m.dstListDir = m.makeListDir(m.Fdst, m.DstIncludeAll)
+	if !m.NoTraverse {
+		m.dstListDir = m.makeListDir(m.Fdst, m.DstIncludeAll)
+	}
 	// Now create the matching transform
 	// ..normalise the UTF8 first
 	m.transforms = append(m.transforms, norm.NFC.String)
@@ -344,7 +347,7 @@ func (m *March) processJob(job listDirJob) (jobs []listDirJob) {
 			srcList, srcListErr = m.srcListDir(job.srcRemote)
 		}()
 	}
-	if !job.noDst {
+	if !m.NoTraverse && !job.noDst {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
@@ -367,6 +370,20 @@ func (m *March) processJob(job listDirJob) (jobs []listDirJob) {
 		return nil
 	}
 
+	// If NoTraverse is set, then try to find a matching object
+	// for each item in the srcList
+	if m.NoTraverse {
+		for _, src := range srcList {
+			if srcObj, ok := src.(fs.Object); ok {
+				leaf := path.Base(srcObj.Remote())
+				dstObj, err := m.Fdst.NewObject(path.Join(job.dstRemote, leaf))
+				if err == nil {
+					dstList = append(dstList, dstObj)
+				}
+			}
+		}
+	}
+
 	// Work out what to do and do it
 	srcOnly, dstOnly, matches := matchListings(srcList, dstList, m.transforms)
 	for _, src := range srcOnly {

fs/sync/sync.go

@@ -29,6 +29,7 @@ type syncCopyMove struct {
 	// internal state
 	ctx            context.Context        // internal context for controlling go-routines
 	cancel         func()                 // cancel the context
+	noTraverse     bool                   // if set don't traverse the dst
 	deletersWg     sync.WaitGroup         // for delete before go routine
 	deleteFilesCh  chan fs.Object         // channel to receive deletes if delete before
 	trackRenames   bool                   // set if we should do server side renames
@@ -75,6 +76,7 @@ func newSyncCopyMove(fdst, fsrc fs.Fs, deleteMode fs.DeleteMode, DoMove bool, de
 		dstFilesResult:     make(chan error, 1),
 		dstEmptyDirs:       make(map[string]fs.DirEntry),
 		srcEmptyDirs:       make(map[string]fs.DirEntry),
+		noTraverse:         fs.Config.NoTraverse,
 		toBeChecked:        newPipe(accounting.Stats.SetCheckQueue, fs.Config.MaxBacklog),
 		toBeUploaded:       newPipe(accounting.Stats.SetTransferQueue, fs.Config.MaxBacklog),
 		deleteFilesCh:      make(chan fs.Object, fs.Config.Checkers),
@@ -84,6 +86,10 @@ func newSyncCopyMove(fdst, fsrc fs.Fs, deleteMode fs.DeleteMode, DoMove bool, de
 		trackRenamesCh:     make(chan fs.Object, fs.Config.Checkers),
 	}
 	s.ctx, s.cancel = context.WithCancel(context.Background())
+	if s.noTraverse && s.deleteMode != fs.DeleteModeOff {
+		fs.Errorf(nil, "Ignoring --no-traverse with sync")
+		s.noTraverse = false
+	}
 	if s.trackRenames {
 		// Don't track renames for remotes without server-side move support.
 		if !operations.CanServerSideMove(fdst) {
@@ -104,6 +110,10 @@ func newSyncCopyMove(fdst, fsrc fs.Fs, deleteMode fs.DeleteMode, DoMove bool, de
 		if s.deleteMode != fs.DeleteModeOff {
 			s.deleteMode = fs.DeleteModeAfter
 		}
+		if s.noTraverse {
+			fs.Errorf(nil, "Ignoring --no-traverse with --track-renames")
+			s.noTraverse = false
+		}
 	}
 	// Make Fs for --backup-dir if required
 	if fs.Config.BackupDir != "" {
@@ -651,6 +661,7 @@ func (s *syncCopyMove) run() error {
 		Fdst:          s.fdst,
 		Fsrc:          s.fsrc,
 		Dir:           s.dir,
+		NoTraverse:    s.noTraverse,
 		Callback:      s,
 		DstIncludeAll: filter.Active.Opt.DeleteExcluded,
 	}

fs/sync/sync_test.go

@@ -61,6 +61,41 @@ func TestCopy(t *testing.T) {
 	fstest.CheckItems(t, r.Fremote, file1)
 }
 
+// Now with --no-traverse
+func TestCopyNoTraverse(t *testing.T) {
+	r := fstest.NewRun(t)
+	defer r.Finalise()
+
+	fs.Config.NoTraverse = true
+	defer func() { fs.Config.NoTraverse = false }()
+
+	file1 := r.WriteFile("sub dir/hello world", "hello world", t1)
+
+	err := CopyDir(r.Fremote, r.Flocal)
+	require.NoError(t, err)
+
+	fstest.CheckItems(t, r.Flocal, file1)
+	fstest.CheckItems(t, r.Fremote, file1)
+}
+
+// Now with --no-traverse
+func TestSyncNoTraverse(t *testing.T) {
+	r := fstest.NewRun(t)
+	defer r.Finalise()
+
+	fs.Config.NoTraverse = true
+	defer func() { fs.Config.NoTraverse = false }()
+
+	file1 := r.WriteFile("sub dir/hello world", "hello world", t1)
+
+	accounting.Stats.ResetCounters()
+	err := Sync(r.Fremote, r.Flocal)
+	require.NoError(t, err)
+
+	fstest.CheckItems(t, r.Flocal, file1)
+	fstest.CheckItems(t, r.Fremote, file1)
+}
+
 // Test copy with depth
 func TestCopyWithDepth(t *testing.T) {
 	r := fstest.NewRun(t)