rename disk.OpenFile to Open which will do os.Open (which will be read-only). disk.OpenFile will do os.OpenFile (which can be rw, append)

pkg/donut/donut-v1.go

@@ -576,7 +576,7 @@ func (donut API) getBucketMetadataReaders() (map[int]io.ReadCloser, error) {
 	}
 	var bucketMetaDataReader io.ReadCloser
 	for order, disk := range disks {
-		bucketMetaDataReader, err = disk.OpenFile(filepath.Join(donut.config.DonutName, bucketMetadataConfig))
+		bucketMetaDataReader, err = disk.Open(filepath.Join(donut.config.DonutName, bucketMetadataConfig))
 		if err != nil {
 			continue
 		}