feat(v2): 支付宝 adapter 落地 RefundingProvider(TradeRefund 同步退款,out_request_no=refund_id 幂等)

2026-07-10 17:29:59 +08:00
parent 2016c5d16e
commit cc6f8fb972
2 changed files with 170 additions and 1 deletions
@@ -31,12 +31,36 @@ func (p *Provider) Method() string { return "alipay" }
 func (p *Provider) Capabilities() provider.Capabilities {
 	return provider.Capabilities{
 		RenderTypes:      []provider.RenderType{provider.RenderRedirect},
-		SupportsRefund:   false, // 退款 P4
+		SupportsRefund:   true, // P4:alipay.trade.refund 同步退款
 		SettleCurrencies: []string{"CNY"},
 		Regions:          []string{"cn"},
 	}
 }

+// Refund 调 alipay.trade.refund(同步接口)。providerRef=out_trade_no(alipay 归位键),
+// refundID 作 out_request_no(部分退款必传且须唯一稳定 → 幂等)。IsFailure()==false 即成功
+// (FundChange=N 表重复退款已幂等,仍算成功)。
+func (p *Provider) Refund(ctx context.Context, providerRef, refundID string, amountMinor int64, reason string) (string, provider.PaidStatus, error) {
+	amt, err := money.Format(amountMinor, "CNY")
+	if err != nil {
+		return "", provider.PaidFailed, err
+	}
+	rsp, err := p.client.TradeRefund(ctx, sw.TradeRefund{
+		OutTradeNo:   providerRef,
+		RefundAmount: amt,
+		RefundReason: reason,
+		OutRequestNo: refundID,
+	})
+	if err != nil {
+		return "", provider.PaidFailed, fmt.Errorf("alipay: 退款请求失败: %w", err)
+	}
+	if rsp.IsFailure() {
+		return "", provider.PaidFailed, fmt.Errorf("alipay: 退款被拒: %w", rsp.Error)
+	}
+	// 退款在支付宝侧以 out_request_no 定位;refundRef 回传我方退款单号(= out_request_no)。
+	return refundID, provider.PaidSucceeded, nil
+}
+
 func (p *Provider) Create(_ context.Context, req provider.CreateRequest) (*provider.Session, error) {
 	if req.Currency != "CNY" {
 		return nil, fmt.Errorf("alipay: 仅支持 CNY, got %s", req.Currency)
@@ -0,0 +1,145 @@
+package alipay_test
+
+import (
+	"context"
+	"crypto"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/sha256"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	sw "github.com/smartwalle/alipay/v3"
+
+	"github.com/wangjia/pay/internal/provider"
+	ali "github.com/wangjia/pay/internal/provider/alipay"
+)
+
+// fakeAlipayRefund 返回一份用"支付宝侧"私钥签名的 alipay.trade.refund 响应。
+func fakeAlipayRefund(t *testing.T, aliPriv *rsa.PrivateKey, fundChange string) *httptest.Server {
+	t.Helper()
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		node := map[string]any{
+			"code": "10000", "msg": "Success",
+			"trade_no": "2021AAA", "out_trade_no": "PAY-1",
+			"refund_fee": "199.00", "fund_change": fundChange,
+		}
+		nodeJSON, _ := json.Marshal(node)
+		// 支付宝对 response node 的原文做 RSA2 签名(sign_type=RSA2)。
+		h := sha256.Sum256(nodeJSON)
+		sig, _ := rsa.SignPKCS1v15(rand.Reader, aliPriv, crypto.SHA256, h[:])
+		resp := map[string]any{
+			"alipay_trade_refund_response": json.RawMessage(nodeJSON),
+			"sign":                         base64.StdEncoding.EncodeToString(sig),
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(resp)
+	}))
+}
+
+// buildRefundClient 与 alipay_test.go 的 genKeys/buildClient 同一套约定:
+//
+// ⚠️ 与 brief 草稿的差异(执行时发现,已按 SDK 实际要求修正,和 alipay_test.go 注释一致):
+//  1. LoadAliPayPublicKey 内部走 PKIX(SubjectPublicKeyInfo)解码,不是 PKCS1 ——
+//     用 x509.MarshalPKIXPublicKey 而非 MarshalPKCS1PublicKey。
+//  2. smartwalle v3.2.29 没有 sw.WithGateway 这个 option;设置网关的是
+//     WithSandboxGateway(gateway)/WithProductionGateway(gateway)。client 用
+//     production=false 建(沙箱),对应用 WithSandboxGateway 把 host 指到 httptest。
+func buildRefundClient(t *testing.T, gateway string, aliPub *rsa.PublicKey) *sw.Client {
+	t.Helper()
+	app, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatalf("gen app key: %v", err)
+	}
+	c, err := sw.New(
+		"2021000000000000",
+		base64.StdEncoding.EncodeToString(x509.MarshalPKCS1PrivateKey(app)),
+		false,
+		sw.WithSandboxGateway(gateway),
+	)
+	if err != nil {
+		t.Fatalf("new client: %v", err)
+	}
+	aliPubDER, err := x509.MarshalPKIXPublicKey(aliPub)
+	if err != nil {
+		t.Fatalf("marshal ali pub: %v", err)
+	}
+	if err := c.LoadAliPayPublicKey(base64.StdEncoding.EncodeToString(aliPubDER)); err != nil {
+		t.Fatalf("load pub: %v", err)
+	}
+	return c
+}
+
+func TestAlipayRefundSyncSuccess(t *testing.T) {
+	aliKey, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatalf("gen ali key: %v", err)
+	}
+	ts := fakeAlipayRefund(t, aliKey, "Y")
+	defer ts.Close()
+	p := ali.New(buildRefundClient(t, ts.URL, &aliKey.PublicKey))
+
+	if !p.Capabilities().SupportsRefund {
+		t.Fatal("alipay Capabilities.SupportsRefund 应为 true")
+	}
+	ref, status, err := p.Refund(context.Background(), "PAY-1", "rf-123", 19900, "用户申请")
+	if err != nil {
+		t.Fatalf("refund: %v", err)
+	}
+	if status != provider.PaidSucceeded || ref != "rf-123" {
+		t.Fatalf("refund result: ref=%s status=%s", ref, status)
+	}
+}
+
+// FundChange=N 表示重复退款(同 out_request_no 幂等命中,支付宝侧未再发生资金变化)——
+// 仍是"受理成功",不能当失败处理,否则重试路径会把已完成的退款误判为失败。
+func TestAlipayRefundIdempotentNoFundChange(t *testing.T) {
+	aliKey, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatalf("gen ali key: %v", err)
+	}
+	ts := fakeAlipayRefund(t, aliKey, "N")
+	defer ts.Close()
+	p := ali.New(buildRefundClient(t, ts.URL, &aliKey.PublicKey))
+
+	ref, status, err := p.Refund(context.Background(), "PAY-1", "rf-123", 19900, "用户申请")
+	if err != nil {
+		t.Fatalf("refund: %v", err)
+	}
+	if status != provider.PaidSucceeded || ref != "rf-123" {
+		t.Fatalf("refund result: ref=%s status=%s", ref, status)
+	}
+}
+
+// 渠道拒绝(如金额超出可退余额)返回 code!=10000 的失败响应 —— TradeRefund 应把
+// rsp.Error 包出去,refundRef 留空,状态归 PaidFailed。
+func TestAlipayRefundChannelRejected(t *testing.T) {
+	aliKey, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatalf("gen ali key: %v", err)
+	}
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		node := map[string]any{
+			"code": "40004", "msg": "Business Failed",
+			"sub_code": "ACQ.TRADE_HAS_FINISHED", "sub_msg": "交易已完结",
+		}
+		nodeJSON, _ := json.Marshal(node)
+		resp := map[string]any{"alipay_trade_refund_response": json.RawMessage(nodeJSON)}
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(resp)
+	}))
+	defer ts.Close()
+	p := ali.New(buildRefundClient(t, ts.URL, &aliKey.PublicKey))
+
+	ref, status, err := p.Refund(context.Background(), "PAY-1", "rf-123", 19900, "用户申请")
+	if err == nil {
+		t.Fatal("want 渠道拒绝返回 error")
+	}
+	if status != provider.PaidFailed || ref != "" {
+		t.Fatalf("refund result: ref=%q status=%s", ref, status)
+	}
+}