ElggUser::getExternalAttributes PHP Method

    public static final function getExternalAttributes()
    {
        return ['name' => null, 'username' => null, 'password_hash' => null, 'email' => null, 'language' => null, 'banned' => "no", 'admin' => 'no', 'prev_last_action' => null, 'last_login' => null, 'prev_last_login' => null];
    }

 /**
  * Hook to transform a search result to an Elgg Entity
  *
  * @param string $hook        the name of the hook
  * @param string $type        the type of the hook
  * @param Client $returnvalue current return value
  * @param array  $params      supplied params
  *
  * @return void|Client
  */
 public static function sourceToEntity($hook, $type, $returnvalue, $params)
 {
     $hit = elgg_extract('hit', $params);
     $index = elgg_extract('_index', $hit);
     $elgg_index = elasticsearch_get_setting('index');
     if ($index !== $elgg_index) {
         return;
     }
     $source = elgg_extract('_source', $hit);
     $row = new \stdClass();
     foreach ($source as $key => $value) {
         switch ($key) {
             case 'subtype':
                 // elastic stores the textual version of the subtype, entity_row_to_elggstar needs the int
                 $row->{$key} = get_subtype_id($source['type'], $value);
                 break;
             case 'last_action':
             case 'time_created':
             case 'time_updated':
                 // convert the timestamps to unix timestamps
                 $value = strtotime($value);
             default:
                 $row->{$key} = $value;
                 break;
         }
     }
     // enabled attribute is not stored in elasticsearch by default
     $row->enabled = 'yes';
     // specials types
     if ($row->type == 'user') {
         // makes sure all attributes are loaded to prevent a db call
         $external_attributes = \ElggUser::getExternalAttributes();
         foreach ($external_attributes as $key => $value) {
             if (isset($row->{$key})) {
                 continue;
             }
             $row->{$key} = $value;
         }
     }
     try {
         $result = entity_row_to_elggstar($row);
     } catch (\Exception $e) {
         elgg_log($e->getMessage(), 'NOTICE');
         return;
     }
     return $result;
 }