func getImage(s *graph.TagStore, img, imgID string) (string, error) { // both Image and ImageID is actually ids, nothing to guess if strings.HasPrefix(imgID, img) { return img, nil } id, err := s.GetID(img) if err != nil { if err == graph.ErrNameIsNotExist { return imgID, nil } return "", err } if id != imgID { return imgID, nil } return img, nil }