diff --git a/weed/filer/filechunks.go b/weed/filer/filechunks.go
index 5a600a188..4c732ddcd 100644
--- a/weed/filer/filechunks.go
+++ b/weed/filer/filechunks.go
@@ -52,11 +52,11 @@ func ETagChunks(chunks []*filer_pb.FileChunk) (etag string) {
 	if len(chunks) == 1 {
 		return fmt.Sprintf("%x", util.Base64Md5ToBytes(chunks[0].ETag))
 	}
-	md5_digests := [][]byte{}
+	var md5Digests [][]byte
 	for _, c := range chunks {
-		md5_digests = append(md5_digests, util.Base64Md5ToBytes(c.ETag))
+		md5Digests = append(md5Digests, util.Base64Md5ToBytes(c.ETag))
 	}
-	return fmt.Sprintf("%x-%d", util.Md5(bytes.Join(md5_digests, nil)), len(chunks))
+	return fmt.Sprintf("%x-%d", util.Md5(bytes.Join(md5Digests, nil)), len(chunks))
 }
 
 func CompactFileChunks(lookupFileIdFn wdclient.LookupFileIdFunctionType, chunks []*filer_pb.FileChunk) (compacted, garbage []*filer_pb.FileChunk) {