需要的参数：session_id, timeStamp, nonceStr, package, paySign, appid,uuid
session_id是协议获取
timeStamp, nonceStr, package, paySign, appid是订单数据
uuid是调用接口获取

1. 第一步要获取小程序的sessionId 基于pc协议不风控
   
2. 获取订单数据timeStamp, nonceStr, package, paySign, appid
   调用https://open.weixin.qq.com/wxaruntime/getuuid?session_id= 获取uuid
3. 调用接口获取到的uuid拼接https://api.weixin.qq.com/wxaruntime/readqrcode?uuid=转二维码

代码奉上

public String pay(String appId,String timeStamp,String nonceStr,String packages,String paySign,String sessionId){Map<String, Object> map = new HashMap<>();map.put("adUxInfo","");map.put("provider","wxpay");map.put("timeStamp",timeStamp);map.put("nonceStr",nonceStr);map.put("package",packages);map.put("paySign",paySign);map.put("signType","MD5");map.put("cookie","busid=wxapp; appid="+appId+";; busid=wxapp; sessionid=;; busid=wxapp; scene=1001;; busid=wxapp; scene_note=");map.put("grantMessageQuota",true);Map<String, Object> map1 = new HashMap<>();map1.put("args", JSON.toJSONString(map));map1.put("isBridgedJsApi",true);map1.put("jsapiType","appservice");map1.put("miniprogramAppID",appId);map1.put("name","requestPayment");map1.put("transitiveData","");Map<String, Object> map2 = new HashMap();map2.put("invokeData",JSON.toJSONString(map1));map2.put("pathType",1);map2.put("rumtimeAppid",appId);map2.put("runtimeSessionId",sessionId);map2.put("runtimeTicket","Product");Map<String, Object> map3 = new HashMap<>();map3.put("appid",appId);map3.put("req_data",JSON.toJSONString(map2));String body = HttpRequest.post("https://open.weixin.qq.com/wxaruntime/getuuid?session_id=" + sessionId).body(JSONObject.toJSONString(map3)).header("Host","open.weixin.qq.com").header("Accept","*/*").header("Content-Type","application/x-www-form-urlencoded").header("Expect","100-continue").execute().body();if (!StrUtil.contains(body,"uuid")){return null;}return QrCodeUtil.generateAsBase64("https://api.weixin.qq.com/wxaruntime/readqrcode?uuid="+ JSONObject.parseObject(body).getString("uuid"), new QrConfig(300,300), "jpg");}