code: func FullDockerRef(p *d2acommon.ParsedDockerURL) string {
  	fds := path.Join(p.IndexURL, p.ImageName)
  	digest := p.Digest
  	tag := p.Tag
  
  	if digest != "" {
  		fds += "@" + digest
  	} else {
  		fds += ":" + tag
  	}
  
  	return fds
  }
docs: // FullDockerRef return the docker reference populated with all the default values.
  // References like "busybox" or "registry-1.docker.io/library/busybox:latest"
  // will become the same docker reference.