From a4c4ddf052c54f32234e224c8590b207cf79caa7 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Wed, 17 Mar 2021 09:48:25 +0000
Subject: [PATCH] vfs: rename files in cache and cancel uploads on directory
 rename

Before this change rclone did not cancel an uploads or rename the
cached files in the directory cache when a directory was renamed.

This caused issues with uploads arriving in the wrong place on bucket
based file systems.

See: https://forum.rclone.org/t/after-a-directory-renmane-using-mv-files-are-not-visible-any-longer/22797
---
 vfs/dir.go                 |  9 +++++++
 vfs/vfscache/cache.go      | 55 +++++++++++++++++++++++++++++++++-----
 vfs/vfscache/cache_test.go |  8 +++---
 3 files changed, 62 insertions(+), 10 deletions(-)

diff --git a/vfs/dir.go b/vfs/dir.go
index 97b812287..083f93921 100644
--- a/vfs/dir.go
+++ b/vfs/dir.go
@@ -322,11 +322,20 @@ func (d *Dir) rename(newParent *Dir, fsDir fs.Directory) {
 	d.modTime = fsDir.ModTime(context.TODO())
 	d.modTimeMu.Unlock()
 	d.mu.Lock()
+	oldPath := d.path
 	d.parent = newParent
 	d.entry = fsDir
 	d.path = fsDir.Remote()
+	newPath := d.path
 	d.read = time.Time{}
 	d.mu.Unlock()
+
+	// Rename in the cache
+	if d.vfs.cache != nil && d.vfs.cache.DirExists(oldPath) {
+		if err := d.vfs.cache.DirRename(oldPath, newPath); err != nil {
+			fs.Infof(d, "Dir.Rename failed in Cache: %v", err)
+		}
+	}
 }
 
 // addObject adds a new object or directory to the directory
diff --git a/vfs/vfscache/cache.go b/vfs/vfscache/cache.go
index 45fc98554..4bf8e80e0 100644
--- a/vfs/vfscache/cache.go
+++ b/vfs/vfscache/cache.go
@@ -135,7 +135,7 @@ func New(ctx context.Context, fremote fs.Fs, opt *vfscommon.Options, avFn AddVir
 	}
 
 	// Remove any empty directories
-	c.purgeEmptyDirs()
+	c.purgeEmptyDirs("", true)
 
 	// Create a channel for cleaner to be kicked upon out of space con
 	c.kick = make(chan struct{}, 1)
@@ -344,6 +344,49 @@ func (c *Cache) Rename(name string, newName string, newObj fs.Object) (err error
 	return nil
 }
 
+// DirExists checks to see if the directory exists in the cache or not.
+func (c *Cache) DirExists(name string) bool {
+	path := c.toOSPath(name)
+	_, err := os.Stat(path)
+	return err == nil
+}
+
+// DirRename the dir in cache
+func (c *Cache) DirRename(oldDirName string, newDirName string) (err error) {
+	// Make sure names are / suffixed for reading keys out of c.item
+	if !strings.HasSuffix(oldDirName, "/") {
+		oldDirName += "/"
+	}
+	if !strings.HasSuffix(newDirName, "/") {
+		newDirName += "/"
+	}
+
+	// Find all items to rename
+	var renames []string
+	c.mu.Lock()
+	for itemName := range c.item {
+		if strings.HasPrefix(itemName, oldDirName) {
+			renames = append(renames, itemName)
+		}
+	}
+	c.mu.Unlock()
+
+	// Rename the items
+	for _, itemName := range renames {
+		newPath := newDirName + itemName[len(oldDirName):]
+		renameErr := c.Rename(itemName, newPath, nil)
+		if renameErr != nil {
+			err = renameErr
+		}
+	}
+
+	// Old path should be empty now so remove it
+	c.purgeEmptyDirs(oldDirName[:len(oldDirName)-1], false)
+
+	fs.Infof(oldDirName, "vfs cache: renamed dir in cache to %q", newDirName)
+	return err
+}
+
 // Remove should be called if name is deleted
 //
 // This returns true if the file was in the transfer queue so may not
@@ -555,15 +598,15 @@ func (c *Cache) purgeOld(maxAge time.Duration) {
 }
 
 // Purge any empty directories
-func (c *Cache) purgeEmptyDirs() {
+func (c *Cache) purgeEmptyDirs(dir string, leaveRoot bool) {
 	ctx := context.Background()
-	err := operations.Rmdirs(ctx, c.fcache, "", true)
+	err := operations.Rmdirs(ctx, c.fcache, dir, leaveRoot)
 	if err != nil {
-		fs.Errorf(c.fcache, "vfs cache: failed to remove empty directories from cache: %v", err)
+		fs.Errorf(c.fcache, "vfs cache: failed to remove empty directories from cache path %q: %v", dir, err)
 	}
-	err = operations.Rmdirs(ctx, c.fcacheMeta, "", true)
+	err = operations.Rmdirs(ctx, c.fcacheMeta, dir, leaveRoot)
 	if err != nil {
-		fs.Errorf(c.fcache, "vfs cache: failed to remove empty directories from metadata cache: %v", err)
+		fs.Errorf(c.fcache, "vfs cache: failed to remove empty directories from metadata cache path %q: %v", dir, err)
 	}
 }
 
diff --git a/vfs/vfscache/cache_test.go b/vfs/vfscache/cache_test.go
index 1052a0f93..5a2401df4 100644
--- a/vfs/vfscache/cache_test.go
+++ b/vfs/vfscache/cache_test.go
@@ -279,7 +279,7 @@ func TestCacheOpenMkdir(t *testing.T) {
 
 	// clean the cache
 	c.purgeOld(-10 * time.Second)
-	c.purgeEmptyDirs()
+	c.purgeEmptyDirs("", true)
 
 	assert.Equal(t, []string(nil), itemAsString(c))
 
@@ -407,7 +407,7 @@ func TestCachePurgeOverQuota(t *testing.T) {
 	// Check only potato2 removed to get below quota
 	c.purgeOverQuota(10)
 	assert.Equal(t, int64(5), c.used)
-	c.purgeEmptyDirs()
+	c.purgeEmptyDirs("", true)
 
 	assert.Equal(t, []string{
 		`name="sub/dir/potato" opens=0 size=5`,
@@ -416,7 +416,7 @@ func TestCachePurgeOverQuota(t *testing.T) {
 	// Now purge everything
 	c.purgeOverQuota(1)
 	assert.Equal(t, int64(0), c.used)
-	c.purgeEmptyDirs()
+	c.purgeEmptyDirs("", true)
 
 	assert.Equal(t, []string(nil), itemAsString(c))
 
@@ -485,7 +485,7 @@ func TestCachePurgeClean(t *testing.T) {
 	// So we use purgeOverQuota here for the cleanup.
 	c.purgeOverQuota(1)
 
-	c.purgeEmptyDirs()
+	c.purgeEmptyDirs("", true)
 
 	assert.Equal(t, []string(nil), itemAsString(c))
 }