code: func (m *Mercury) GetNodeByName(ctx context.Context, nodename string) (*types.Node, error) {
  	key := fmt.Sprintf(nodePodKey, nodename)
  	ev, err := m.GetOne(ctx, key)
  	if err != nil {
  		return nil, err
  	}
  
  	podname := string(ev.Value)
  	return m.GetNode(ctx, podname, nodename)
  }
docs: // GetNodeByName get node by name
  // first get podname from `/node/pod/:nodename`
  // then call GetNode