// Object Operations

func countOnlineDisks(onlineDisks []StorageAPI) (online int) {
	for _, onlineDisk := range onlineDisks {
		if onlineDisk != nil && onlineDisk.IsOnline() {
			online++
		}
	}
	return online
}

// CopyObject - copy object source object to destination object.
// if source object and destination object are same we only
// update metadata.