public function index(IndexRequest $request)
    {
        $user = $request->user();
        $pageSize = 20;
        $page = $request->get('page', 1);
        list($items, $unreadCount) = $this->repository->getItems($user, $page, $pageSize);
        return $this->sendResponse([
            'items'  => $items,
            'unread' => $unreadCount
        ], '');
    }