# 微信支付

**Repository Path**: wheres-cute/wechat_payment

## Basic Information

- **Project Name**: 微信支付
- **Description**: 各个场景下微信支付，h5+小程序+云开发等等。通过这个demo，对微信sdk有了深入的了解。分享，转发，支付都进行了实践，微信小程序支付相对简单微信小程序对一些支付流程进行保护，h5支付相对比较复杂，对明码暗码的加密，加密算法的操作比较繁琐。不过都需要微信公众号的支持
- **Primary Language**: JavaScript
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 4
- **Created**: 2020-09-04
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

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 * @Author: 柯基与佩奇
 * @Date: 2020-08-19 11:45:56
 * @LastEditTime: 2020-08-20 14:46:33
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# 微信支付

#### 介绍

各个场景下微信支付，h5+小程序+云开发等等

# node egg 微信支付服务

1. 初始化egg应用

``` js
npm init egg--type = simple
npm i
```

2. 配置微信支付用到的插件

plugin.js 必备插件(egg-wechat-pay可以选择别的插件代替)

``` js
module.exports = {
    cors: {
        enable: true,
        package: 'egg-cors',
    },
    wechatPay: {
        enable: true,
        package: 'egg-wechat-pay'
    },
};
```

3. 配置中间件

因为微信支付返回的数据都是xml格式数据 所以我们的解析xml数据 不然接收不到微信支付回调的请求数据
xmlparse.js (可以使用koa的其它中间件也行)

``` js
module.exports = require('co-wechat-body');
```

4. 配置config.default.js

``` js
//部分主要配置
config.security = {
    csrf: {
        enable: false,
    },
    domainWhiteList: ['*'],
} //跨域请求

const fs = require('fs')
const path = require('path')

config.mpWeixin = {
    appid: '', // 微信公众号或小程序号
    AppSecret: '', // 密钥
    Host: 'https://api.weixin.qq.com/',
    MsgToken: '',
    EncodingAESKey: ''
}

config.wechatPay = {
    client: {
        bodyPrefix: '', //
        appId: '', //微信公众号或小程序号
        merchantId: '', //商户号
        secret: '', //商户密钥
        notifyUrl: '', //支付成功回调地址
        REFUNDNotifyUrl: '', //退款成功回调地址
        pfx: fs.readFileSync(path.join(__dirname, '../app/public/wxpaly/apiclient_cert.p12')) //退款证书地址
    },
    URLS: {
        UNIFIED_ORDER: 'https://api.mch.weixin.qq.com/pay/unifiedorder',
        ORDER_QUERY: 'https://api.mch.weixin.qq.com/pay/orderquery',
        REFUND: 'https://api.mch.weixin.qq.com/secapi/pay/refund',
        REFUND_QUERY: 'https://api.mch.weixin.qq.com/pay/refundquery',
        DOWNLOAD_BILL: 'https://api.mch.weixin.qq.com/pay/downloadbill',
        SHORT_URL: 'https://api.mch.weixin.qq.com/tools/shorturl',
        CLOSE_ORDER: 'https://api.mch.weixin.qq.com/pay/closeorder',
        REDPACK_SEND: 'https://api.mch.weixin.qq.com/mmpaymkttransfers/sendredpack',
        REDPACK_QUERY: 'https://api.mch.weixin.qq.com/mmpaymkttransfers/gethbinfo',
        TRANSFERS: 'https://api.mch.weixin.qq.com/mmpaymkttransfers/promotion/transfers',
        TRANSFERS_QUERY: 'https://api.mch.weixin.qq.com/mmpaymkttransfers/gettransferinfo',
    }
}
```

5. 工具函数util.js

``` js
const crypto = require('crypto');
const fs = require('fs')
const path = require('path')

function randomString(len) {
    // isFinite 判断是否为有限数值
    if (!Number.isFinite(len)) {
        throw new TypeError('Expected a finite number');
    }
    return crypto.randomBytes(Math.ceil(len / 2)).toString('hex').slice(0, len);
}

function getSign(params, key, type = 'MD5') { //支付签名
    const paramsArr = Object.keys(params);
    paramsArr.sort();
    const stringArr = []
    paramsArr.map(key => {
        if (key != 'sign' && params[key])
            stringArr.push(key + '=' + params[key]);
    })
    if (type == "MD5") {
        // 最后加上 商户Key
        stringArr.push("key=" + key)
        const string = stringArr.join('&');
        const MD5 = crypto.createHash('md5');
        return MD5.update(string).digest('hex').toUpperCase();
    } else {
        return crypto.createHmac('sha256', key)
            .update(stringArr.join('&'))
            .digest('hex').toUpperCase();
    }

}

function checkSign(params, key) { //验证签名是否正确
    const {
        sign
    } = params;
    const Newsign = getSign(params, key)
    if (sign === Newsign) {
        return true
    } else {
        return false
    }
}
```

6. 编写Service

Payment.js

``` js
'use strict';
const Service = require('egg').Service;
const {
    randomString,
    ransign,
    getSign,
    checkSign,
} = require('util.js')
const moment = require('moment');
const Decimal = require('decimal.js');
class PaymentService extends Service {

    /**
     * H5支付或微信扫一扫支付
     *
     * @param {*} body 费用说明
     * @param {*} money 金额
     * @returns
     * @memberof PaymentService
     */
    async pay(PayType, body, money) {
        const {
            ctx,
            service,
            app
        } = this;
        let No = Date.now();
        let OrderNo = moment().format('YYYYMMDDHHmm') + randomString(3) + No;
        let createTime = moment().format('YYYY-MM-DD HH:mm:ss');
        let order = { //统一订单参数
            device_info: 'WEB',
            body,
            out_trade_no: OrderNo,
            total_fee: new Decimal(money).mul(new Decimal(100)).toFixed(),
            attach: `${UserId}`
        };
        if (PayType == 'H5') {
            order.scene_info = JSON.stringify({
                h5_info: 'h5_info',
                type: 'Wap',
                wap_url: this.config.h5host,
                wap_name: '峰会报名付款'
            })
        }
        const unifiedRes = await this.unifiedOrder(order, PayType == 'H5' ? 'MWEB' : 'NATIVE');
        return unifiedRes
    }

    //支付回调
    async payaction(params) {
        const {
            ctx,
            service,
            app
        } = this;
        const {
            appid, //公众账号ID
            bank_type, //付款银行
            cash_fee, //现金支付金额
            device_info, //设备号
            fee_type, //货币种类
            is_subscribe, //是否关注公众账号
            mch_id, //商户号
            nonce_str, //随机字符串
            openid, //用户标识
            out_trade_no, //商户订单号
            result_code, //业务结果
            return_code, //返回状态码
            sign, //签名
            time_end, //支付完成时间
            total_fee, //订单金额
            trade_type, //交易类型
            transaction_id, //微信支付订单号
            attach
        } = params;

        if (return_code == "SUCCESS") {
            if (checkSign(params, this.config.wechatPay.client.secret)) { //解析回调数据是否正确
                //自己处理
            } else {
                return {
                    msg: '签名错误',
                    status: 'error',
                }
            }
        } else {
            return {
                msg: '支付失败',
                status: 'error',
            }
        }
    }

    //退款
    async refund(out_trade_no, refund_fee, refund_desc, PayPrice) {
        const {
            ctx,
            service,
            app
        } = this;

        let nonce_str = randomString(32);

        let out_refund_no = moment().format('YYYYMMDDHHmmss') + randomString(25);

        let data = {
            appid: this.config.wechatPay.client.appId,
            mch_id: this.config.wechatPay.client.merchantId,
            nonce_str, //随机字符串
            out_trade_no, //订单号
            out_refund_no, //退款订单号
            total_fee: new Decimal(PayPrice).mul(new Decimal(100)).toFixed(), //总金额
            refund_fee: new Decimal(refund_fee).mul(new Decimal(100)).toFixed(), //退款金额
            refund_desc, //退款原因描述
            notify_url: this.config.wechatPay.client.REFUNDNotifyUrl //退款成功回调地址
        }
        let sign = getSign(data, this.config.wechatPay.client.secret); //签名
        let xml = {
            ...data,
            sign
        };
        try {
            const curlres = await ctx.curl( `${this.config.wechatPay.URLS.REFUND}` , {
                method: 'POST',
                pfx: this.config.wechatPay.client.pfx, //退款证书
                passphrase: this.config.wechatPay.client.merchantId,
                // 直接发送原始 xml 数据，不需要 HttpClient 做特殊处理
                content: this.app.wechatPay.stringify(xml),
            });

            let rdata = await this.app.wechatPay.parse(curlres.data); //解析xml数据

            return {
                res: rdata
            }
        } catch (error) {
            console.log(error, "error");
            if (error == "invalid refund_fee") {
                return {
                    msg: '退款金额不正确',
                    status: 'error',
                }
            } else {
                return {
                    msg: '退款失败',
                    status: 'error',
                }
            }

        }

    }

    //微信内部浏览器或小程序 统一创建支付 
    async CreatePaymentInfo(money, openid) {
        const {
            ctx,
            service,
            app
        } = this;

        let No = Date.now();
        let OrderNo = moment().format('YYYYMMDDHHmmss') + randomString(3) + No;
        const order = { //统一订单参数
            device_info: 'WEB',
            body: "",
            费用说明
            out_trade_no: OrderNo, //订单编号
            total_fee: new Decimal(money).mul(new Decimal(100)).toFixed(), //支付金额 分为单位
            openid, //用户openid
        };
        const res = await this.unifiedOrder(order); //请求生成订单信息
        return {
            res
        }
    }

    async unifiedOrder(order, trade_type = 'JSAPI') {
        const {
            ctx,
            service
        } = this;
        let nonce_str = randomString(32); //随机字符串
        let Data = {
            appid: this.config.wechatPay.client.appId,
            mch_id: this.config.wechatPay.client.merchantId, //商户号
            nonce_str,
            sign_type: 'MD5', //签名方式
            spbill_create_ip: ctx.ip, //用户ip
            trade_type, //支付类型
            notify_url: this.config.wechatPay.client.notifyUrl, //支付成功回调地址
            time_expire: moment().add(1, 'h').format('YYYYMMDDHHmmss'),
            ...order
        }

        let sign = getSign(Data, this.config.wechatPay.client.secret); //签名
        let xml = {
            ...Data,
            sign
        };
        const cur = await ctx.curl( `${this.config.wechatPay.URLS.UNIFIED_ORDER}` , {
            method: 'POST',
            // 直接发送原始 xml 数据，不需要 HttpClient 做特殊处理
            content: this.app.wechatPay.stringify(xml),
        });
        const parseData = await this.app.wechatPay.parse(cur.data);
        let res = {
            appId: Data.appid,
            nonceStr: nonce_str,
            package: `prepay_id=${parseData.prepay_id}` ,
            timeStamp: moment().add(1, 'h').unix().toString(),
            signType: 'MD5',
        }
        if (trade_type == 'MWEB') { //手机浏览器H5支付
            res.mweb_url = parseData.mweb_url
        }

        if (trade_type == 'NATIVE') { //可用于微信扫一扫支付
            res.code_url = parseData.code_url
        }

        return {
            ...res,
            paySign: getSign(res, this.config.wechatPay.client.secret)
        }
    }

}

module.exports = PaymentService;
```