public function actionItem()
 {
     $request = Yii::$app->request;
     try {
         $id = $request->get('id', '');
         $id = HtmlPurifier::process($id);
         $document = Documents::getDocumentById($id);
         Yii::$app->view->title = $document['name'];
         $related_documents = Documents::getRelatedDocuments();
         Yii::$app->view->registerMetaTag(['name' => 'description', 'content' => $document['description']]);
         Yii::$app->view->registerMetaTag(['property' => 'og:title', 'content' => $document['name']]);
         Yii::$app->view->registerMetaTag(['property' => 'og:description', 'content' => $document['description']]);
         Yii::$app->view->registerMetaTag(['property' => 'og:image', 'content' => Util::makeUrlImage($document['preview'])]);
         return $this->render('item', ['data' => $document, 'related_documents' => $related_documents]);
     } catch (Exception $ex) {
     }
 }