node-微信小程序（微信支付）

var xmlreader = require("xmlreader");

var wxpay = {

    //把金额转为分
    getmoney: function (money) {
        return parseFloat(money) * 100;
    },

    // 随机字符串产生函数  
    createNonceStr: function () {
        return Math.random().toString(36).substr(2, 15);
    },

    // 时间戳产生函数  
    createTimeStamp: function () {
        return parseInt(new Date().getTime() / 1000) + ‘‘;
    },

    //签名加密算法
    paysignjsapi: function (appid, body, mch_id, nonce_str, notify_url, openid, out_trade_no, spbill_create_ip, total_fee, trade_type, mchkey) {
        var ret = {
            appid: appid,
            mch_id: mch_id,
            nonce_str: nonce_str,
            body: body,
            notify_url: notify_url,
            openid: openid,
            out_trade_no: out_trade_no,
            spbill_create_ip: spbill_create_ip,
            total_fee: total_fee,
            trade_type: trade_type
        };
        var string = raw(ret);
        var key = mchkey;
        string = string + ‘&key=‘ + key;
        var crypto = require(‘crypto‘);
        return crypto.createHash(‘md5‘).update(string, ‘utf8‘).digest(‘hex‘).toUpperCase();
    },
    // 小程序签名
    paysignjsapimini: function (appId, nonceStr, package, signType, timestamp, mchkey) {
        var ret = {
            appId: appId,
            nonceStr: nonceStr,
            package: package,
            signType: signType,
            timeStamp: timestamp,
        };
        var string = raw(ret);
        var key = mchkey;
        string = string + ‘&key=‘ + key;
        var crypto = require(‘crypto‘);
        return crypto.createHash(‘md5‘).update(string, ‘utf8‘).digest(‘hex‘).toUpperCase();
    },
    getXMLNodeValue: function (xml) {
        xmlreader.read(xml, function (errors, response) {
            if (null !== errors) {
                console.log(errors)
                return;
            }
            var prepay_id = response.xml.prepay_id.text();
            return prepay_id;
        });
    }

}
function raw(args) {
    var keys = Object.keys(args);
    keys = keys.sort()
    var newArgs = {};
    keys.forEach(function (key) {
        newArgs[key] = args[key];
    });
    var string = ‘‘;
    for (var k in newArgs) {
        string += ‘&‘ + k + ‘=‘ + newArgs[k];
    }
    string = string.substr(1);
    return string;
}

module.exports = wxpay;

static async _wxPay(ctx) {
    //首先拿到前端传过来的参数
    let orderCode = ‘2020090202‘;
    let money = ‘0.01‘;
    let openid = ‘oc2a-4jkdE7zVV-RjamMWf-wErsQ‘;

    //首先生成签名sign
    // appid
    let mch_id = mchid;
    let nonce_str = wxpay.createNonceStr();
    let timestamp = wxpay.createTimeStamp();
    let body = ‘测试微信支付‘;
    let out_trade_no = orderCode;
    let total_fee = wxpay.getmoney(money);
    let spbill_create_ip = ‘116.199.41.58‘; // 支持IPV4和IPV6两种格式的IP地址。调用微信支付API的机器IP
    let notify_url = wxurl;
    let trade_type = ‘JSAPI‘;  // ‘APP‘;公众号：‘JSAPI‘或‘NATIVE‘

    let sign = wxpay.paysignjsapi(appid, body, mch_id, nonce_str, notify_url, openid, out_trade_no, spbill_create_ip, total_fee, trade_type, mchkey);

    //组装xml数据
    var formData = "";
    formData += "" + appid + "";  //appid
    formData += "";
    formData += "" + mch_id + "";  //商户号
    formData += "" + nonce_str + ""; //随机字符串，不长于32位。
    formData += "" + notify_url + "";
    formData += "" + openid + "";
    formData += "" + out_trade_no + "";
    formData += "" + spbill_create_ip + "";
    formData += "" + total_fee + "";
    formData += "" + trade_type + "";
    formData += "" + sign + "";
    formData += "";

    var url = ‘https://api.mch.weixin.qq.com/pay/unifiedorder‘;

    let promise = new Promise(function(resolve, reject) {

        request({ url: url, method: ‘POST‘, body: formData }, function (err, response, body) {
          if (!err && response.statusCode == 200) {
      
            xmlreader.read(body.toString("utf-8"), function (errors, response) {
              if (null !== errors) {
                console.log(errors)
                return;
              }
              var prepay_id = response.xml.prepay_id.text();
              //将预支付订单和其他信息一起签名后返回给前端
              let package1 = "prepay_id=" + prepay_id;
              let signType = "MD5";
              let minisign = wxpay.paysignjsapimini(appid, nonce_str, package1, signType, timestamp, mchkey);
              let json = JSON.stringify({ status: ‘200‘, data: { ‘appId‘: appid, ‘partnerId‘: mchid, ‘prepayId‘: prepay_id, ‘nonceStr‘: nonce_str, ‘timeStamp‘: timestamp, ‘package‘: ‘Sign=WXPay‘,‘paySign‘: minisign } })
              resolve(json)
            });
          }
        });
    });
    await promise.then((res)=>{
      ctx.body = CommonSend.list(res)
    })
    
  }