请求参数：

{"sp_mchid":"1628769043","sub_mchid":"1424440102","sp_appid":"wx1d297adcc992d247","sub_appid":"wxeb6c52b53e729611","out_trade_no":"69285884857675776","description":"订单支付","attach":"203306","notify_url":"https://client.hiranwu.com/wxpay/notify","amount":{"total":1999,"currency":"CNY"},"payer":{"sub_openid":"oHH8Y0asbe5g2JbWM5d9GwHTdmlM"}}