sampleDockerConfig := fmt.Sprintf(`{
   "%s": {
     "email": %q,
     "auth": %q
   }
}`, test.globURL, email, auth)

		keyring := &BasicDockerKeyring{}
		if cfg, err := ReadDockerConfigFileFromBytes([]byte(sampleDockerConfig)); err != nil {
			t.Errorf("Error processing json blob %q, %v", sampleDockerConfig, err)
		} else {
			keyring.Add(cfg)
		}