function _valid_perform(&$request, &$response)
  {
    if (!$this->dataspace->get('group_id'))
    {
      $request->set_status(REQUEST_STATUS_FAILURE);
      return;
    }

    $links_manager = new links_manager();

    $result = $links_manager->update_links_group(
        $this->dataspace->get('group_id'),
        $this->dataspace->get('identifier'),
        $this->dataspace->get('title')
    );

    if ($result !== false)
    {
      $request->set_status(REQUEST_STATUS_FORM_SUBMITTED);

      if($request->has_attribute('popup'))
        $response->write(close_popup_response($request));
    }
    else
      $request->set_status(REQUEST_STATUS_FAILURE);
  }
 function _valid_perform()
 {
     if (!$this->dataspace->get('group_id')) {
         return new failed_response();
     }
     $links_manager = new links_manager();
     $result = $links_manager->update_links_group($this->dataspace->get('group_id'), $this->dataspace->get('identifier'), $this->dataspace->get('title'));
     if ($result !== false) {
         return new close_popup_response(RESPONSE_STATUS_FORM_SUBMITTED);
     } else {
         return new failed_response();
     }
 }