Add log into MoveBucket and clone the key

Signed-off-by: Benjamin Wang <benjamin.ahrtr@gmail.com>

Author: ahrtr

bucket.go

@@ -285,19 +285,21 @@ func (b *Bucket) DeleteBucket(key []byte) (err error) {
 		return errors.ErrTxNotWritable
 	}
 
+	newKey := cloneBytes(key)
+
 	// Move cursor to correct position.
 	c := b.Cursor()
-	k, _, flags := c.seek(key)
+	k, _, flags := c.seek(newKey)
 
 	// Return an error if bucket doesn't exist or is not a bucket.
-	if !bytes.Equal(key, k) {
+	if !bytes.Equal(newKey, k) {
 		return errors.ErrBucketNotFound
 	} else if (flags & common.BucketLeafFlag) == 0 {
 		return errors.ErrIncompatibleValue
 	}
 
 	// Recursively delete all child buckets.
-	child := b.Bucket(key)
+	child := b.Bucket(newKey)
 	err = child.ForEachBucket(func(k []byte) error {
 		if err := child.DeleteBucket(k); err != nil {
 			return fmt.Errorf("delete bucket: %s", err)
@@ -309,15 +311,15 @@ func (b *Bucket) DeleteBucket(key []byte) (err error) {
 	}
 
 	// Remove cached copy.
-	delete(b.buckets, string(key))
+	delete(b.buckets, string(newKey))
 
 	// Release all bucket pages to freelist.
 	child.nodes = nil
 	child.rootNode = nil
 	child.free()
 
 	// Delete the node if we have a matching key.
-	c.node().del(key)
+	c.node().del(newKey)
 
 	return nil
 }
@@ -328,48 +330,62 @@ func (b *Bucket) DeleteBucket(key []byte) (err error) {
 //  2. or the key already exists in the destination bucket;
 //  3. or the key represents a non-bucket value;
 //  4. the source and destination buckets are the same.
-func (b *Bucket) MoveBucket(key []byte, dstBucket *Bucket) error {
+func (b *Bucket) MoveBucket(key []byte, dstBucket *Bucket) (err error) {
+	lg := b.tx.db.Logger()
+	lg.Debugf("Moving bucket %q", string(key))
+	defer func() {
+		if err != nil {
+			lg.Errorf("Moving bucket %q failed: %v", string(key), err)
+		} else {
+			lg.Debugf("Moving bucket %q successfully", string(key))
+		}
+	}()
+
 	if b.tx.db == nil || dstBucket.tx.db == nil {
 		return errors.ErrTxClosed
 	} else if !dstBucket.Writable() {
 		return errors.ErrTxNotWritable
 	}
 
+	newKey := cloneBytes(key)
+
 	// Move cursor to correct position.
 	c := b.Cursor()
-	k, v, flags := c.seek(key)
+	k, v, flags := c.seek(newKey)
 
 	// Return an error if bucket doesn't exist or is not a bucket.
-	if !bytes.Equal(key, k) {
+	if !bytes.Equal(newKey, k) {
 		return errors.ErrBucketNotFound
 	} else if (flags & common.BucketLeafFlag) == 0 {
-		return fmt.Errorf("key %q isn't a bucket in the source bucket: %w", key, errors.ErrIncompatibleValue)
+		lg.Errorf("An incompatible key %s exists in the source bucket", string(newKey))
+		return errors.ErrIncompatibleValue
 	}
 
 	// Do nothing (return true directly) if the source bucket and the
 	// destination bucket are actually the same bucket.
 	if b == dstBucket || (b.RootPage() == dstBucket.RootPage() && b.RootPage() != 0) {
-		return fmt.Errorf("source bucket %s and target bucket %s are the same: %w", b.String(), dstBucket.String(), errors.ErrSameBuckets)
+		lg.Errorf("The source bucket (%s) and the target bucket (%s) are the same bucket", b.String(), dstBucket.String())
+		return errors.ErrSameBuckets
 	}
 
 	// check whether the key already exists in the destination bucket
 	curDst := dstBucket.Cursor()
-	k, _, flags = curDst.seek(key)
+	k, _, flags = curDst.seek(newKey)
 
 	// Return an error if there is an existing key in the destination bucket.
-	if bytes.Equal(key, k) {
+	if bytes.Equal(newKey, k) {
 		if (flags & common.BucketLeafFlag) != 0 {
 			return errors.ErrBucketExists
 		}
-		return fmt.Errorf("key %q already exists in the target bucket: %w", key, errors.ErrIncompatibleValue)
+		lg.Errorf("An incompatible key %s exists in the target bucket", string(newKey))
+		return errors.ErrIncompatibleValue
 	}
 
 	// remove the sub-bucket from the source bucket
-	delete(b.buckets, string(key))
-	c.node().del(key)
+	delete(b.buckets, string(newKey))
+	c.node().del(newKey)
 
 	// add te sub-bucket to the destination bucket
-	newKey := cloneBytes(key)
 	newValue := cloneBytes(v)
 	curDst.node().put(newKey, newKey, newValue, 0, common.BucketLeafFlag)