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