public function fetchGroupMembers()
    {
        $url = sprintf($this->vbot->config['server.uri.base'].'/webwxbatchgetcontact?type=ex&r=%s&pass_ticket=%s',
            time(), $this->vbot->config['server.passTicket']
        );

        $list = [];
        $this->vbot->groups->each(function ($item, $key) use (&$list) {
            $list[] = ['UserName' => $key, 'EncryChatRoomId' => ''];
        });

        $content = $this->vbot->http->json($url, [
            'BaseRequest' => $this->vbot->config['server.baseRequest'],
            'Count'       => $this->vbot->groups->count(),
            'List'        => $list,
        ], true, ['timeout' => 60]);

        $this->storeMembers($content);
    }