code: public function getId($aData = [])
      {
          $sIds       = '';
          $oInput     = Factory::service('Input');
          $oHttpCodes = Factory::service('HttpCodes');
  
          if (!empty($oInput->get('id'))) {
              $sIds = $oInput->get('id');
          }
  
          if (!empty($oInput->get('ids'))) {
              $sIds = $oInput->get('ids');
          }
  
          $aIds = explode(',', $sIds);
          $aIds = array_filter($aIds);
          $aIds = array_unique($aIds);
  
          if (count($aIds) > self::CONFIG_MAX_ITEMS_PER_REQUEST) {
              throw new ApiException(
                  'You can request a maximum of ' . self::CONFIG_MAX_ITEMS_PER_REQUEST . ' items per request',
                  $oHttpCodes::STATUS_BAD_REQUEST
              );
          }
  
          // --------------------------------------------------------------------------
  
          $oItemModel = Factory::model(
              static::CONFIG_MODEL_NAME,
              static::CONFIG_MODEL_PROVIDER
          );
          $aResults   = $oItemModel->getByIds($aIds, $aData);
  
          if ($oInput->get('id')) {
              $oItem = reset($aResults);
              $mData = $oItem ? $this->formatObject($oItem) : null;
          } else {
              $mData = array_map([$this, 'formatObject'], $aResults);
          }
  
          $oResponse = Factory::factory('ApiResponse', 'nails/module-api');
          $oResponse->setData($mData);
          return $oResponse;
      }
docs: Return an item by it's ID, or an array of items by their ID.
  
  @return array