code: func (q *ParentIdQuery) Source() (interface{}, error) {
  	// {
  	//   "parent_id" : {
  	//       "type" : "blog",
  	//       "id" : "1"
  	//   }
  	// }
  	source := make(map[string]interface{})
  	query := make(map[string]interface{})
  	source["parent_id"] = query
  
  	query["type"] = q.typ
  	query["id"] = q.id
  	if q.boost != nil {
  		query["boost"] = *q.boost
  	}
  	if q.ignoreUnmapped != nil {
  		query["ignore_unmapped"] = *q.ignoreUnmapped
  	}
  	if q.queryName != "" {
  		query["_name"] = q.queryName
  	}
  	if q.innerHit != nil {
  		src, err := q.innerHit.Source()
  		if err != nil {
  			return nil, err
  		}
  		query["inner_hits"] = src
  	}
  	return source, nil
  }
docs: // Source returns JSON for the parent_id query.