public function processRequest()
 {
     $request = $this->getRequest();
     $document = $request->getStr('document');
     $draft_key = $request->getStr('draftkey');
     if ($draft_key) {
         $table = new PhabricatorDraft();
         queryfx($table->establishConnection('w'), 'INSERT INTO %T (authorPHID, draftKey, draft) VALUES (%s, %s, %s)
       ON DUPLICATE KEY UPDATE draft = VALUES(draft)', $table->getTableName(), $request->getUser()->getPHID(), $draft_key, $document);
     }
     $content_obj = new PhrictionContent();
     $content_obj->setContent($document);
     $engine = PhabricatorMarkupEngine::newPhrictionMarkupEngine();
     $content = $content_obj->renderContent();
     return id(new AphrontAjaxResponse())->setContent($content);
 }