Ошибка при обращении к функциям modx в классе.

private function Import($f){
	global $modx;
	.......
	$result = $modx->query('SELECT isfolder FROM '.$modx->getFullTableName('site_content').' WHERE id='.$dirId);
	echo $modx->db->getValue($result);
	.......
}

Fatal error: Call to undefined method DocumentParser::query() in F:\-=soft-install=-\-=Graphic_video_audio_html_editors=-\xamp\xampp\htdocs\modx\assets\modules\importer\include\controller.class.php on line 189