code: func (m *Mercury) SaveProcessing(ctx context.Context, opts *types.DeployOptions, nodeInfo types.NodeInfo) error {
  	processingKey := filepath.Join(containerProcessingPrefix, opts.Name, opts.Entrypoint.Name, nodeInfo.Name, opts.ProcessIdent)
  	_, err := m.Create(ctx, processingKey, fmt.Sprintf("%d", nodeInfo.Deploy))
  	return err
  }
docs: // SaveProcessing save processing status in etcd