code: public function jsonSerialize()
      {
          $json = parent::jsonSerialize();
  
          if (null !== $this->forfetching) {
              $json['forfetching'] = $this->forfetching;
          }
  
          return $json;
      }
docs: Gets all data that should be available in a json representation.
  
  @return array an associative array of the available variables