public function fetchCurrentMenu ()
    {
        $request = new Request("GET", "https://api.weixin.qq.com/cgi-bin/menu/get");
        $response = $this->client->send($request);
        $json = json_decode((string)$response->getBody());

        if (! isset($json->menu->button)) {
            throw new Exception('Unexpected menu JSON structure: `menu.button` not found', $response);
        }

        $menu = new Menu();

        foreach ($json->menu->button as $item) {
            $menu = $menu->withItem($this->inflateItem($item));
        }

        return $menu;
    }