微信支付 - 退款通知 (#359)

* 🆕 发起退款 - 添加notify_url参数

* 🆕 退款通知

pay/notify/refund.go

@@ -0,0 +1,77 @@
+package notify
+
+import (
+	"crypto/md5"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/xml"
+	"errors"
+
+	"github.com/silenceper/wechat/v2/util"
+)
+
+// reference: https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=9_16&index=10
+
+// RefundedResult 退款回调
+type RefundedResult struct {
+	ReturnCode *string `xml:"return_code"`
+	ReturnMsg  *string `xml:"return_msg"`
+
+	AppID    *string `xml:"appid"`
+	MchID    *string `xml:"mch_id"`
+	NonceStr *string `xml:"nonce_str"`
+	ReqInfo  *string `xml:"req_info"`
+}
+
+// RefundedReqInfo 退款结果（明文）
+type RefundedReqInfo struct {
+	TransactionID       *string `xml:"transaction_id"`
+	OutTradeNO          *string `xml:"out_trade_no"`
+	RefundID            *string `xml:"refund_id"`
+	OutRefundNO         *string `xml:"out_refund_no"`
+	TotalFee            *int    `xml:"total_fee"`
+	SettlementTotalFee  *int    `xml:"settlement_total_fee"`
+	RefundFee           *int    `xml:"refund_fee"`
+	SettlementRefundFee *int    `xml:"settlement_refund_fee"`
+	RefundStatus        *string `xml:"refund_status"`
+	SuccessTime         *string `xml:"success_time"`
+	RefundRecvAccount   *string `xml:"refund_recv_account"`
+	RefundAccount       *string `xml:"refund_account"`
+	RefundRequestSource *string `xml:"refund_request_source"`
+}
+
+// RefundedResp 消息通知返回
+type RefundedResp struct {
+	ReturnCode string `xml:"return_code"`
+	ReturnMsg  string `xml:"return_msg"`
+}
+
+// DecryptReqInfo 对退款结果进行解密
+func (notify *Notify) DecryptReqInfo(result *RefundedResult) (*RefundedReqInfo, error) {
+	var err error
+	if result == nil || result.ReqInfo == nil {
+		return nil, errors.New("empty refunded_result or req_info")
+	}
+
+	base64Decode, err := base64.StdEncoding.DecodeString(*result.ReqInfo)
+	if err != nil {
+		return nil, err
+	}
+
+	hash := md5.New()
+	if _, err = hash.Write([]byte(notify.Key)); err != nil {
+		return nil, err
+	}
+	md5APIKey := hex.EncodeToString(hash.Sum(nil))
+
+	data, err := util.AesECBDecrypt(base64Decode, []byte(md5APIKey))
+	if err != nil {
+		return nil, err
+	}
+
+	res := &RefundedReqInfo{}
+	if err = xml.Unmarshal(data, res); err != nil {
+		return nil, err
+	}
+	return res, nil
+}

pay/notify/refund_test.go

@@ -0,0 +1,26 @@
+package notify
+
+import (
+	"encoding/xml"
+	"testing"
+
+	"github.com/silenceper/wechat/v2/pay/config"
+)
+
+func TestNotify_DecryptReqInfo(t *testing.T) {
+	// data_source: https://studygolang.com/articles/11811
+	notify := &Notify{Config: &config.Config{Key: "ziR0QKsTUfMOuochC9RfCdmfHECorQAP"}}
+	info := "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"
+	res, err := notify.DecryptReqInfo(&RefundedResult{ReqInfo: &info})
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	bytes, err := xml.Marshal(res)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	t.Log(string(bytes))
+}