code: func (s *HTTPServer) parseMetaFilter(req *http.Request) map[string]string {
  	if filterList, ok := req.URL.Query()["node-meta"]; ok {
  		filters := make(map[string]string)
  		for _, filter := range filterList {
  			key, value := ParseMetaPair(filter)
  			filters[key] = value
  		}
  		return filters
  	}
  	return nil
  }
docs: // parseMetaFilter is used to parse the ?node-meta=key:value query parameter, used for
  // filtering results to nodes with the given metadata key/value