golang实现微信支付v3版本

快乐源泉 · · 2424 次点击 · · 开始浏览

这是一个创建于的文章，其中的信息可能已经有所发展或是发生改变。

一、准备阶段

获取私钥

官方文档 https://kf.qq.com/faq/161222N...
获取私钥证书的序列号 https://pay.weixin.qq.com/wik...

openssl x509 -in 1900009191_20180326_cert.pem -noout -serial
serial=1DDE55AD98ED71D6EDD4A4A16996DE7B47773A8C

私钥获取后有三个文件

apiclient_key.p12 
apiclient_cert.pem  
apiclient_key.pem

本次示例程序中，使用的是文件 apiclient_key.pem内容

获取公钥(平台证书)

官方文档
更新证书 https://pay.weixin.qq.com/wik...
平台证书会提前10天生成新证书，微信官方推荐在旧证书过期前5-10天部署新证书
获取证书API文档 https://pay.weixin.qq.com/wik...
身份证认证信息生成文档 https://pay.weixin.qq.com/wik...

常量

const appId = ""           // 小程序或者公众号的appid
const mchId = ""           // 微信支付的商户id
const privateSerialNo = "" // 私钥证书号
const aesKey = ""          // 微信支付aes key'

需要用的包


import (
    "crypto"
    "crypto/aes"
    "crypto/cipher"
    cryptoRand "crypto/rand"
    "crypto/rsa"
    "crypto/sha256"
    "crypto/x509"
    "encoding/base64"
    "encoding/pem"
    "errors"
    "fmt"
    "math/rand"
    "time"
)


import (
    "bytes"
    "crypto"
    "encoding/json"
    "errors"
    "fmt"
    "io/ioutil"
    "net/http"
    "net/url"
    "os"
    "sync"
    "time"
)

生成数字签名

// 对消息的散列值进行数字签名
func signPKCS1v15(msg, privateKey []byte, hashType crypto.Hash) ([]byte, error) {
    block, _ := pem.Decode(privateKey)
    if block == nil {
        return nil, errors.New("private key decode error")
    }
    pri, err := x509.ParsePKCS8PrivateKey(block.Bytes)
    if err != nil {
        return nil, errors.New("parse private key error")
    }
    key, ok := pri.(*rsa.PrivateKey)
    if ok == false {
        return nil, errors.New("private key format error")
    }
    sign, err := rsa.SignPKCS1v15(cryptoRand.Reader, key, hashType, msg)
    if err != nil {
        return nil, errors.New("sign error")
    }
    return sign, nil
}
// base编码
func base64EncodeStr(src []byte) string {
    return base64.StdEncoding.EncodeToString(src)
}

生成身份认证信息

func authorization(method string, paramMap map[string]interface{}, rawUrl string) (token string, err error) {
    var body string
    if len(paramMap) != 0 {
        paramJsonBytes, err := json.Marshal(paramMap)
        if err != nil {
            return token, err
        }
        body = string(paramJsonBytes)
    }
    urlPart, err := url.Parse(rawUrl)
    if err != nil {
        return token, err
    }
    canonicalUrl := urlPart.RequestURI()
    timestamp := time.Now().Unix()
    nonce := getRandomString(32)
    message := fmt.Sprintf("%s\n%s\n%d\n%s\n%s\n", method, canonicalUrl, timestamp, nonce, body)
    open, err := os.Open("./private.pem") // 商户私有证书路径或者从数据库读取
    if err != nil {
        return token, err
    }
    defer open.Close()
    privateKey, err := ioutil.ReadAll(open)
    if err != nil {
        return token, err
    }
    signBytes, err := signPKCS1v15(hasha256(message), privateKey, crypto.SHA256)
    if err != nil {
        return token, err
    }
    sign := base64EncodeStr(signBytes)
    token = fmt.Sprintf("mchid=\"%s\",nonce_str=\"%s\",timestamp=\"%d\",serial_no=\"%s\",signature=\"%s\"",
        mchId, nonce, timestamp, privateSerialNo, sign)
    return token, nil
}

报文解密

func decryptGCM(aesKey, nonceV, ciphertextV, additionalDataV string) ([]byte, error) {
    key := []byte(aesKey)
    nonce := []byte(nonceV)
    additionalData := []byte(additionalDataV)
    ciphertext, err := base64.StdEncoding.DecodeString(ciphertextV)
    if err != nil {
        return nil, err
    }
    block, err := aes.NewCipher(key)
    if err != nil {
        return nil, err
    }
    aesGCM, err := cipher.NewGCM(block)
    if err != nil {
        return nil, err
    }
    plaintext, err := aesGCM.Open(nil, nonce, ciphertext, additionalData)
    if err != nil {
        return nil, err
    }
    return plaintext, err
}

获取平台证书

// 获取公钥
const publicKeyUrl = "https://api.mch.weixin.qq.com/v3/certificates"
type TokenResponse struct {
    Data []TokenResponseData `json:"data"`
}
type TokenResponseData struct {
    EffectiveTime      string             `json:"effective_time"`
    EncryptCertificate EncryptCertificate `json:"encrypt_certificate"`
    ExpireTime         string             `json:"expire_time"`
    SerialNo           string             `json:"serial_no"`
}
type EncryptCertificate struct {
    Algorithm      string `json:"algorithm"`
    AssociatedData string `json:"associated_data"`
    Ciphertext     string `json:"ciphertext"`
    Nonce          string `json:"nonce"`
}
var publicSyncMap sync.Map
// 获取公钥
func getPublicKey() (key string, err error) {
    var prepareTime int64 = 24 * 3600 * 3 // 证书提前三天过期旧证书，获取新证书
    nowTime := time.Now().Unix()
    // 读取公钥缓存数据
    cacheValueKey := fmt.Sprintf("app_id:%s:public_key:value", appId)
    cacheExpireTimeKey := fmt.Sprintf("app_id:%s:public_key:expire_time", appId)
    cacheValue, keyValueOk := publicSyncMap.Load(cacheValueKey)
    cacheExpireTime, expireTimeOk := publicSyncMap.Load(cacheExpireTimeKey)
    if keyValueOk && expireTimeOk {
        // 格式化时间
        local, _ := time.LoadLocation("Local")
        location, _ := time.ParseInLocation(time.RFC3339, cacheExpireTime.(string), local)
        // 判断是否过期，证书没有过期直接返回
        if location.Unix()-prepareTime > nowTime {
            return cacheValue.(string), nil
        }
    }
    token, err := authorization(http.MethodGet, nil, publicKeyUrl)
    if err != nil {
        return key, err
    }
    request, err := http.NewRequest(http.MethodGet, publicKeyUrl, nil)
    if err != nil {
        return key, err
    }
    request.Header.Add("Authorization", "WECHATPAY2-SHA256-RSA2048 "+token)
    request.Header.Add("User-Agent", "用户代理(https://zh.wikipedia.org/wiki/User_agent)")
    request.Header.Add("Content-type", "application/json;charset='utf-8'")
    request.Header.Add("Accept", "application/json")
    client := http.DefaultClient
    response, err := client.Do(request)
    if err != nil {
        return key, err
    }
    defer response.Body.Close()
    bodyBytes, err := ioutil.ReadAll(response.Body)
    if err != nil {
        return key, err
    }
    //fmt.Println(string(bodyBytes))
    var tokenResponse TokenResponse
    if err = json.Unmarshal(bodyBytes, &tokenResponse); err != nil {
        return key, err
    }
    for _, encryptCertificate := range tokenResponse.Data {
        // 格式化时间
        local, _ := time.LoadLocation("Local")
        location, err := time.ParseInLocation(time.RFC3339, encryptCertificate.ExpireTime, local)
        if err != nil {
            return key, err
        }
        // 判断是否过期，证书没有过期直接返回
        if location.Unix()-prepareTime > nowTime {
            decryptBytes, err := decryptGCM(aesKey, encryptCertificate.EncryptCertificate.Nonce, encryptCertificate.EncryptCertificate.Ciphertext,
                encryptCertificate.EncryptCertificate.AssociatedData)
            if err != nil {
                return key, err
            }
            key = string(decryptBytes)
            publicSyncMap.Store(cacheValueKey, key)
            publicSyncMap.Store(cacheExpireTimeKey, encryptCertificate.ExpireTime)
            return key, nil
        }
    }
    return key, errors.New("get public key error")
}

二、发起微信支付

jsapi 发起支付

调用统一下单接口

统一下单接口文档 https://pay.weixin.qq.com/wik...

const commonPayUrl = "https://api.mch.weixin.qq.com/v3/pay/transactions/jsapi"

// 统一下单接口
func commonPay() (payResMap map[string]string, err error) {
    payResMap = make(map[string]string)
    amount := 10
    paramMap := make(map[string]interface{})
    paramMap["appid"] = appId
    paramMap["mchid"] = mchId
    paramMap["description"] = fmt.Sprintf("微信充值:￥%d", amount)
    paramMap["out_trade_no"] = fmt.Sprintf("test%s%s", time.Now().Format("20060102150405"), randNumber())
    paramMap["notify_url"] = "http://tools.localhost/notify"
    paramMap["amount"] = map[string]interface{}{"total": amount * 100, "currency": "CNY"}
    paramMap["payer"] = map[string]string{"openid": "123456789"}
    token, err := authorization(http.MethodPost, paramMap, commonPayUrl)
    if err != nil {
        return payResMap, err
    }
    marshal, _ := json.Marshal(paramMap)
    request, err := http.NewRequest(http.MethodPost, commonPayUrl, bytes.NewReader(marshal))
    if err != nil {
        return payResMap, err
    }
    request.Header.Add("Authorization", "WECHATPAY2-SHA256-RSA2048 "+token)
    request.Header.Add("User-Agent", "用户代理(https://zh.wikipedia.org/wiki/User_agent)")
    request.Header.Add("Content-type", "application/json;charset='utf-8'")
    request.Header.Add("Accept", "application/json")
    client := http.DefaultClient
    response, err := client.Do(request)
    if err != nil {
        return payResMap, err
    }
    defer func() {
        response.Body.Close()
    }()
    bodyBytes, err := ioutil.ReadAll(response.Body)
    if err != nil {
        return payResMap, err
    }
    if err = json.Unmarshal(bodyBytes, &payResMap); err != nil {
        return payResMap, err
    }
    if payResMap["prepay_id"] == "" {
        return payResMap, errors.New("code:" + payResMap["code"] + "err:" + payResMap["message"])
    }
    return payResMap, nil
}

生成jsapi发起支付

JSAPI 调起支付接口文档 https://pay.weixin.qq.com/wik...

func jsApi(payResMap map[string]string) (payJson string, err error) {
    payMap := make(map[string]string)
    timeStamp := time.Now().Unix()
    nonce := getRandomString(32)
    packageStr := "prepay_id=" + payResMap["prepay_id"]
    payMap["appId"] = appId
    payMap["timeStamp"] = fmt.Sprintf("%v", timeStamp)
    payMap["nonceStr"] = nonce
    payMap["package"] = packageStr
    // 签名
    message := fmt.Sprintf("%s\n%s\n%s\n%s\n", appId, fmt.Sprintf("%v", timeStamp), nonce, packageStr)
    open, err := os.Open("/Users/apple/data/www/go/work/src/study/testwechantpay/private.pem")
    if err != nil {
        return payJson, err
    }
    defer open.Close()
    privateKey, err := ioutil.ReadAll(open)
    if err != nil {
        return payJson, err
    }
    signBytes, err := signPKCS1v15(hasha256(message), privateKey, crypto.SHA256)
    if err != nil {
        return payJson, err
    }
    sign := base64EncodeStr(signBytes)
    payMap["signType"] = sign
    payMap["paySign"] = "RSA"
    payJsonBytes, err := json.Marshal(payMap)
    if err != nil {
        return payJson, err
    }
    payJson = string(payJsonBytes)
    return payJson, nil
}

前台发起支付js

需要加载微信js http://res.wx.qq.com/open/js/jweixin-1.6.0.js
调用微信js需要在微信支付平台，设置支付目录
指引文档 https://pay.weixin.qq.com/wik...

<script type="text/javascript" src="__STATIC__/frontend/js/jquery.min.js"></script>
<script type="text/javascript" src="http://res.wx.qq.com/open/js/jweixin-1.6.0.js"></script>
<script>  
    $(function () {
        $(".am-btn").click(function () {
            var score = $(".score div input:checked").val();
            $.post("发起微信支付后端接口URL", {"score": score}, function (res) {
                if (res.status === 500) {
                    alert(res.message);
                    return;
                }
                if (typeof WeixinJSBridge == "undefined") {
                    if (document.addEventListener) {
                        document.addEventListener('WeixinJSBridgeReady', onBridgeReady, false);
                    } else if (document.attachEvent) {
                        document.attachEvent('WeixinJSBridgeReady', onBridgeReady);
                        document.attachEvent('onWeixinJSBridgeReady', onBridgeReady);
                    }
                } else {
                    onBridgeReady(res);
                }
            })
        })
        function onBridgeReady(param) {
            var orderId = param.data.orderId;
            WeixinJSBridge.invoke('getBrandWCPayRequest', {
                    "appId": param.data.appId,
                    "timeStamp": param.data.timeStamp,
                    "nonceStr": param.data.nonceStr,
                    "package": param.data.package,
                    "signType": param.data.signType,
                    "paySign": param.data.paySign
                },
                function (res) {
                    if (res.err_msg === "get_brand_wcpay_request:ok") {
                        window.location.href = "{:url('index/order/successful')}?order_id=" + orderId;
                    }
                });
        }
    })
  </script>

三、异步通知

签名校验

文档 https://pay.weixin.qq.com/wik...
验证签名

//验证数字签名
func VerifyRsaSign(msg []byte, sign []byte, publicStr []byte, hashType crypto.Hash) bool {
    //pem解码
    block, _ := pem.Decode(publicStr)
    //x509解码
    publicKeyInterface, err := x509.ParseCertificate(block.Bytes)
    if err != nil {
        panic(err)
    }
    publicKey := publicKeyInterface.PublicKey.(*rsa.PublicKey)
    //验证数字签名
    err = rsa.VerifyPKCS1v15(publicKey, hashType, msg, sign) //crypto.SHA1
    return err == nil
}

// 验证签名
func signatureValidate(timeStamp, rawPost, nonce, signature string) (bool, error) {
    signature = base64DecodeStr(signature)
    message := fmt.Sprintf("%s\n%s\n%s\n", timeStamp, nonce, rawPost)
    publicKey, err := getPublicKey()
    if err != nil {
        return false, err
    }

    return VerifyRsaSign(hasha256(message), []byte(signature), []byte(publicKey), crypto.SHA256), nil
}

报文解密

type NotifyResponse struct {
    CreateTime string         `json:"create_time"`
    Resource   NotifyResource `json:"resource"`
}
type NotifyResource struct {
    Ciphertext     string `json:"ciphertext"`
    AssociatedData string `json:"associated_data"`
    Nonce          string `json:"nonce"`
}
func notifyDecrypt(rawPost string) (decrypt string, err error) {
    var notifyResponse NotifyResponse
    if err = json.Unmarshal([]byte(rawPost), &notifyResponse); err != nil {
        return decrypt, err
    }
    decryptBytes, err := decryptGCM(aesKey, notifyResponse.Resource.Nonce, notifyResponse.Resource.Ciphertext,
        notifyResponse.Resource.AssociatedData)
    if err != nil {
        return decrypt, err
    }
    decrypt = string(decryptBytes)
    return decrypt, nil
}

四、查询订单

文档 https://pay.weixin.qq.com/wik...

查询订单

const searchTradeUrl = "https://api.mch.weixin.qq.com/v3/pay/transactions/out-trade-no/%s?mchid=%s"

// 查询交易
func searchTrade(orderId string) (trade string, err error) {
  rawUrl := fmt.Sprintf(searchTradeUrl, orderId, mchId)
  token, err := authorization(http.MethodGet, nil, rawUrl)
  if err != nil {
      return trade, err
  }
  request, err := http.NewRequest(http.MethodGet, rawUrl, nil)
  if err != nil {
      return trade, err
  }
  request.Header.Add("Authorization", "WECHATPAY2-SHA256-RSA2048 "+token)
  request.Header.Add("User-Agent", "用户代理(https://zh.wikipedia.org/wiki/User_agent)")
  request.Header.Add("Content-type", "application/json;charset='utf-8'")
  request.Header.Add("Accept", "application/json")

  client := http.DefaultClient

  response, err := client.Do(request)
  if err != nil {
      return trade, err
  }
  defer response.Body.Close()

  bodyBytes, err := ioutil.ReadAll(response.Body)
  if err != nil {
      return trade, err
  }

  // 验证签名
  timestamp := response.Header.Get("Wechatpay-Timestamp")
  nonce := response.Header.Get("Wechatpay-Nonce")
  signature := response.Header.Get("Wechatpay-Signature")
  flag, err := signatureValidate(timestamp, string(bodyBytes), nonce, signature)
  if err != nil {
      return trade, err
  }
  if !flag {
      return trade, errors.New("search refund result verify sign error")
  }


  return string(bodyBytes), nil
}

五、申请退款

文档 https://pay.weixin.qq.com/wik...

申请退款

const refundUrl = "https://api.mch.weixin.qq.com/v3/refund/domestic/refunds"

func refundTrade(orderId string, amount float64) (trade string, err error) {
  paramMap := make(map[string]interface{})
  paramMap["out_trade_no"] = orderId
  paramMap["out_refund_no"] = orderId + "-1"
  paramMap["amount"] = map[string]interface{}{"refund": amount * 100, "total": amount * 100, "currency": "CNY"}

  token, err := authorization(http.MethodPost, paramMap, refundUrl)
  if err != nil {
      return trade, err
  }

  marshal, _ := json.Marshal(paramMap)
  request, err := http.NewRequest(http.MethodPost, refundUrl, bytes.NewReader(marshal))
  if err != nil {
      return trade, err
  }
  request.Header.Add("Authorization", "WECHATPAY2-SHA256-RSA2048 "+token)
  request.Header.Add("User-Agent", "用户代理(https://zh.wikipedia.org/wiki/User_agent)")
  request.Header.Add("Content-type", "application/json;charset='utf-8'")
  request.Header.Add("Accept", "application/json")

  client := http.DefaultClient

  response, err := client.Do(request)
  if err != nil {
      return trade, err
  }
  defer func() {
      response.Body.Close()
  }()

  bodyBytes, err := ioutil.ReadAll(response.Body)
  if err != nil {
      return trade, err
  }

  // 验证签名
  timestamp := response.Header.Get("Wechatpay-Timestamp")
  nonce := response.Header.Get("Wechatpay-Nonce")
  signature := response.Header.Get("Wechatpay-Signature")
  flag, err := signatureValidate(timestamp, string(bodyBytes), nonce, signature)
  if err != nil {
      return trade, err
  }
  if !flag {
      return trade, errors.New("search refund result verify sign error")
  }

  return string(bodyBytes), nil
}

有疑问加站长微信联系（非本文作者）

本文来自：Segmentfault

感谢作者：快乐源泉

查看原文：golang实现微信支付v3版本

入群交流（和以上内容无关）：加入Go大咖交流群，或添加微信：liuxiaoyan-s 备注：入群；或加QQ群：692541889

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golang实现微信支付v3版本

一、准备阶段

获取私钥

获取公钥(平台证书)

常量

需要用的包

生成数字签名

生成身份认证信息

报文解密

获取平台证书

二、发起微信支付

jsapi 发起支付

调用统一下单接口

生成jsapi发起支付

前台发起支付js

三、异步通知

签名校验

报文解密

四、查询订单

查询订单

五、申请退款

申请退款

用户登录

今日阅读排行

一周阅读排行

关注我

给该专栏投稿 写篇新文章

收入到我管理的专栏 新建专栏

一、准备阶段

获取私钥

获取公钥(平台证书)

常量

需要用的包

生成数字签名

生成身份认证信息

报文解密

获取平台证书

二、发起微信支付

jsapi 发起支付

调用统一下单接口

生成jsapi发起支付

前台发起支付js

三、异步通知

签名校验

报文解密

四、查询订单

查询订单

五、申请退款

申请退款

给该专栏投稿写篇新文章

收入到我管理的专栏新建专栏