Node.js 实现微信支付分账功能完整流程与代码示例

// @router post -> share -> /common/payment/share
async share() {
 const { ctx } = this
 const nonce_str = ctx.service.wx.randomStr()
 // 商户id
 const mch_id = '123456'
 // x小程序appid
 const appid = 'wx123456'
 // 订单号
 const out_order_no = '1609745196755nFvdMaYub2'
 // 微信支付订单号
 const transaction_id = '4200000801202101044301662433'
 // 商户secrect
 const key = '9813490da1ffb80afaa36f6f1265e490'

 // 这一块的参数官网文档上有详细的说明
 const params = {
  appid,
  mch_id,
  nonce_str,
  out_order_no,
  receivers: `[{"account": "123qwe","amount": 1,"description": "description","type": "PERSONAL_OPENID"}]`,
  sign_type: 'HMAC-SHA256',
  transaction_id,
 }

 // 签名方式必须是HMAC-SHA256
 const sign = ctx.service.wx.sign(params, key, 'HMAC-SHA256')

 // xmlString
 const formData = `<xml>
  <appid>${appid}</appid>
  <mch_id>${mch_id}</mch_id>
  <nonce_str>${nonce_str}</nonce_str> 
  <out_order_no>${out_order_no}</out_order_no>
  <transaction_id>${transaction_id}</transaction_id>
  <sign>${sign}</sign>
  <sign_type>HMAC-SHA256</sign_type>
  <receivers>${params.receivers}</receivers>
 </xml>`

 const res = await ctx.curl(
  "https://api.mch.weixin.qq.com/secapi/pay/profitsharing",
  {
   // 需要使用证书apiclient_cert
   cert: fs.readFileSync(path.join(__dirname,'../../../cert/apiclient_cert.pem')),
   // 需要使用证书apiclient_key
   key: fs.readFileSync(path.join(__dirname,'../../../cert/apiclient_key.pem')),
   method: "post",
   data: formData,
  }
 )

 const datastring = res.data.toString()
 xml2js.parseString(datastring, (err, result) => {
  if (err) {
   ctx.throw(422, err)
  }

  console.log(result)
 })
}


// randomStr
// 生成随机字符串
randomStr(len = 24) {
 const str =
  'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
 let result = '';
 for (let i = 0; i < len; i++) {
  result += str[Math.floor(Math.random() * str.length)];
 }
 return result;
}

// 签名
// mchKey是商户secrect，否则签名不通过
sign(data, mchKey, signType = 'MD5') {
 const keys = [];
 for (const key in data) {
  if (data[key] !== undefined) {
   keys.push(key);
  }
 }
 // 字典排序=>key=value
 const stringA = keys
  .sort()
  .map(key => `${key}=${decodeURIComponent(data[key])}`)
  .join('&');
 // 拼接商户key
 const stringSignTemp = stringA + '&key=' + mchKey;
 // 加密
 let hash;
 if (signType === 'MD5') {
  hash = crypto.createHash('md5').update(stringSignTemp);
 } else {
  hash = crypto.createHmac('sha256', mchKey).update(stringSignTemp, 'utf8');
 }
 
 const paySign = hash.digest('hex').toUpperCase();
 return paySign;
}