Go语言实现支付宝支付与退款详解

go get github.com/go-pay/gopay

type Config struct {
	Appid      string
	MchId      string
	PrivateKey string
	NotifyUrl  string
	RefundUrl  string
	ReturnUrl  string
	PublicKey  string
	QuitUrl    string
}

func NewAlipayService(ctx context.Context, config Config) *AlipayService {
    alipayCli, err := alipay.NewClient(config.Appid, config.PrivateKey, true)
    if err != nil {
        panic(err)
    }
    alipayCli.DebugSwitch = gopay.DebugOn // 开启debug
    alipayCli.SetCharset(alipay.UTF8).SetSignType(alipay.RSA2)
    
    return &AlipayService{
        ctx:    ctx,
        config: config,
        alipay: alipayCli,
    }
}

// PcPay PC端支付
func (a *AlipayService) PcPay(charge *Charge) (string, error) {
	a.alipay = a.alipay.SetReturnUrl(a.config.ReturnUrl).SetNotifyUrl(a.config.NotifyUrl)
	// 生成单号
	amount := decimal.NewFromInt(charge.MoneyFee).DivRound(decimal.NewFromInt(100), 2).String()
	// 构造参数
	bm := make(gopay.BodyMap)
	bm.Set("subject", charge.Describe).
		Set("out_trade_no", charge.TradeNum).
		Set("total_amount", amount).
		Set("qr_pay_mode", 4).
		Set("qrcode_width", 120)
	// 发起支付
	return a.alipay.TradePagePay(a.ctx, bm)
}

// WapPay WAP端支付
func (a *AlipayService) WapPay(charge *Charge) (string, error) {
	a.alipay = a.alipay.SetReturnUrl(a.config.ReturnUrl).SetNotifyUrl(a.config.NotifyUrl)
	// 生成单号
	amount := decimal.NewFromInt(charge.MoneyFee).DivRound(decimal.NewFromInt(100), 2).String()
	// 构造参数
	bm := make(gopay.BodyMap)
	bm.Set("subject", charge.Describe).
		Set("out_trade_no", charge.TradeNum).
		Set("total_amount", amount).
		Set("quit_url", a.config.QuitUrl+a.config.QuitUrl).
		Set("product_code", "FAST_INSTANT_TRADE_PAY")
	// 发起支付
	return a.alipay.TradeWapPay(a.ctx, bm)
}

// AndroidPay Android端支付
func (a *AlipayService) AndroidPay(charge *Charge) (string, error) {

	a.alipay.SetNotifyUrl(a.config.NotifyUrl)

	amount := decimal.NewFromInt(charge.MoneyFee).DivRound(decimal.NewFromInt(100), 2).String()
	// 构造参数
	bm := make(gopay.BodyMap)
	bm.Set("subject", charge.Describe).
		Set("out_trade_no", charge.TradeNum).
		Set("total_amount", amount).
		Set("product_code", "FAST_INSTANT_TRADE_PAY")
	// 发起支付
	return a.alipay.TradeAppPay(a.ctx, bm)
}

// AliWebPayResult 支付宝支付结果回调
type AliWebPayResult struct {
	OutTradeNo  string `json:"out_trade_no"`
	TradeStatus string `json:"trade_status"`
}

// GetNotifyResult  解析支付回调
func (a *AlipayService) GetNotifyResult(r *http.Request) (result *AliWebPayResult, err error) {
	// 解析异步通知的参数
	notifyReq, err := alipay.ParseNotifyToBodyMap(r)
	if err != nil {
		// TODO 处理错误信息
		return
	}

	// 支付宝异步通知验签（公钥模式）
	_, err = alipay.VerifySign(a.config.PublicKey, notifyReq)
	if err != nil {
		// TODO 处理错误信息
		return
	}
	if err = notifyReq.Unmarshal(result); err != nil {
		// TODO 处理错误信息
		return
	}
	return
}

// RefundCharge 退款参数
type RefundCharge struct {
   TradeNum     string `json:"tradeNum,omitempty"`
   MoneyFee     int64  `json:"MoneyFee,omitempty"`
   OutRefundNo  string `json:"out_refund_no,omitempty"`
   RefundReason string `json:"refund_reason,omitempty"`
}


func (a *AlipayService) Refund(charge *RefundCharge) (err error) {
	amount := decimal.NewFromInt(charge.MoneyFee).DivRound(decimal.NewFromInt(100), 2).String()
	// 构造参数
	bm := make(gopay.BodyMap)
	bm.Set("out_trade_no", charge.TradeNum).
		Set("refund_reason", charge.RefundReason).
		Set("out_request_no", charge.OutRefundNo).
		Set("refund_amount", amount)
	// 发起支付
	res, err := a.alipay.TradeRefund(a.ctx, bm)
	//TODO 处理错误信息，处理结果
	return
}