当前位置 博文首页 > golang实现微信支付v3版本的方法
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
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("/Users/apple/data/www/go/work/src/study/testwechantpay/private.pem")
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")
}
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...
// 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": "opCO05utXkPQh3Vje13WjEdQpAZ4"}
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_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_jb51code">
//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 notifyValidate(timeStamp ,nonce,rawPost,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), ¬ifyResponse); 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
}
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
}
return string(bodyBytes), nil
}
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
}
return string(bodyBytes), nil
}
