how to init the AlipayClient when using labrador

[jiangxiaoqiang]

when using java, we should initial client like this:

AlipayClient alipayClient = new DefaultAlipayClient(gatewayUrl, appMap.getThirdAppId(), appMap.getAppPrivateKey(), "json", AlipayConstants.CHARSET_UTF8, appMap.getAppPublicKey(), AlipayConstants.SIGN_TYPE_RSA2);

when using labrador, there only a appkey parameters:

let client = AlipayClient::<RedisStorage>::new(&amap.third_app_id, false);

how to pass into other config? like private key publickey