public function send(array $params, $type = self::TYPE_NORMAL)
    {
        $api = ($type === self::TYPE_NORMAL) ? self::API_SEND : self::API_SEND_GROUP;

        $params['wxappid'] = $this->merchant->app_id;
        //如果类型为分裂红则去掉client_ip参数,否则签名会出错
        if ($type === self::TYPE_GROUP) {
            unset($params['client_ip']);
        }

        return $this->request($api, $params);
    }