feat(backend): pay 下单/查单切 v2 契约——sku 直用 biz_code、session 多态响应、金额 int64 分

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend/internal/service/pay.go

@@ -9,7 +9,6 @@ import (
 	"net/http"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/google/uuid"
@@ -20,7 +19,8 @@ import (
 	"github.com/wangjia/jiu/backend/internal/util"
 )
 
-// PayService jiu ↔ pay 收款中枢对接（契约 ~/code/pay-contract openapi.yaml v1.0.0）。
+// PayService jiu ↔ pay 收款中枢对接（下单/查单已切 pay v2 契约 /api/v2/orders，
+// webhook 回调仍为 v1 契约，见 HandleCallback）。
 // 四块职责：下单（CreatePurchase）、webhook 入账（HandleCallback）、续期（entitle）、查单兜底（reconcileOnce）。
 type PayService struct {
 	db      *gorm.DB
@@ -28,10 +28,6 @@ type PayService struct {
 	secret  string
 	retURL  string
 	client  *http.Client
-
-	prodMu    sync.Mutex
-	prodCache map[string]int64 // biz_code -> pay product_id
-	prodAt    time.Time
 }
 
 var (
@@ -82,17 +78,22 @@ func (s *PayService) Configured() bool { return s.secret != "" }
 
 // ---------- ① 购买下单 ----------
 
+// PurchaseResult 下单结果。RenderType/Payload/AmountMinor/Currency/Subject 是 pay v2 契约的一手字段；
+// PayURL/Amount 是给官网 checkout 与旧客户端读的兼容字段（Deprecated，观察一版后视情况收敛）。
 type PurchaseResult struct {
-	PayURL     string `json:"pay_url"`
 	OutTradeNo  string         `json:"out_trade_no"`
-	Amount     string `json:"amount"`
+	RenderType  string         `json:"render_type"`
+	Payload     map[string]any `json:"payload"`
+	AmountMinor int64          `json:"amount_minor"`
+	Currency    string         `json:"currency"`
 	Subject     string         `json:"subject"`
+	PayURL      string         `json:"pay_url"` // Deprecated: render_type==redirect 时 = payload.url
+	Amount      string         `json:"amount"`  // Deprecated: formatMinor(AmountMinor) 分转元字符串
 }
 
-// CreatePurchase 建购买记录并调 pay 下单，返回收银台跳转 URL。
+// CreatePurchase 建购买记录并调 pay 下单，返回收银台会话（session）。
-// clientType（契约 v1.1.0，"pc"/"mobile"/""）：显式端型透传给 pay 决定收银台形态
+// clientType（"pc"/"mobile"/""）：pay v2 契约暂未透传端型决定收银台形态的参数，
-// （mobile=手机网站支付拉起支付宝 App / pc=电脑扫码页）；服务端间调用下单请求 UA
+// 端型透传能力欠账，pay 补契约后跟进；本参数先保留签名不 breaking 调用方。
-// 是本后端的，不传则 pay 会按 Go client UA 误判为 PC。
 func (s *PayService) CreatePurchase(shopID, userID uint64, bizCode, clientType string) (*PurchaseResult, error) {
 	if !s.Configured() {
 		return nil, ErrPayNotConfigured
@@ -110,44 +111,73 @@ func (s *PayService) CreatePurchase(shopID, userID uint64, bizCode, clientType s
 		}
 	}
 
-	productID, err := s.productID(bizCode)
-	if err != nil {
-		return nil, fmt.Errorf("获取套餐信息失败: %w", err)
-	}
-
 	p := model.LicensePurchase{ShopID: shopID, UserID: userID, ProductBizCode: bizCode, Status: "pending"}
 	if err := s.db.Create(&p).Error; err != nil {
 		return nil, err
 	}
 
 	payload := map[string]any{
-		"product_id": productID,
+		"sku":        bizCode,
+		"method":     "alipay",
 		"biz_system": "jiu",
 		"biz_ref":    strconv.FormatUint(p.ID, 10),
 		"return_url": s.retURL,
 	}
-	if clientType != "" {
-		payload["client_type"] = clientType
-	}
 	reqBody, _ := json.Marshal(payload)
-	respBody, err := s.signedPost("/api/v1/orders", reqBody)
+	respBody, err := s.signedPost("/api/v2/orders", reqBody)
 	if err != nil {
 		return nil, fmt.Errorf("pay 下单失败: %w", err)
 	}
 	var resp struct {
-		Data PurchaseResult `json:"data"`
+		Data struct {
+			OrderNo string `json:"order_no"`
+			Session struct {
+				RenderType string         `json:"render_type"`
+				Payload    map[string]any `json:"payload"`
+			} `json:"session"`
+		} `json:"data"`
 	}
-	if err := json.Unmarshal(respBody, &resp); err != nil || resp.Data.PayURL == "" || resp.Data.OutTradeNo == "" {
+	if err := json.Unmarshal(respBody, &resp); err != nil || resp.Data.OrderNo == "" || resp.Data.Session.RenderType == "" {
 		return nil, fmt.Errorf("pay 下单响应异常")
 	}
 
-	if err := s.db.Model(&model.LicensePurchase{}).Where("id = ?", p.ID).Updates(map[string]any{
+	result := &PurchaseResult{
-		"out_trade_no": resp.Data.OutTradeNo,
+		OutTradeNo: resp.Data.OrderNo,
-		"amount":       resp.Data.Amount,
+		RenderType: resp.Data.Session.RenderType,
-	}).Error; err != nil {
+		Payload:    resp.Data.Session.Payload,
+	}
+	if result.RenderType == "redirect" {
+		if u, ok := result.Payload["url"].(string); ok {
+			result.PayURL = u
+		}
+	}
+
+	updates := map[string]any{
+		"out_trade_no": result.OutTradeNo,
+		"pay_url":      result.PayURL,
+	}
+	// best-effort 查单回填金额：查单失败不阻断下单，金额留 0 由 D1 兜底（对账/结果页轮询会补）
+	if st, err := s.queryOrder(result.OutTradeNo); err == nil {
+		result.AmountMinor = st.AmountMinor
+		result.Currency = st.Currency
+		result.Subject = st.Subject
+		updates["amount_minor"] = st.AmountMinor
+		updates["currency"] = st.Currency
+	}
+	result.Amount = formatMinor(result.AmountMinor)
+
+	if err := s.db.Model(&model.LicensePurchase{}).Where("id = ?", p.ID).Updates(updates).Error; err != nil {
 		return nil, err
 	}
-	return &resp.Data, nil
+	return result, nil
+}
+
+// formatMinor 分→元字符串（仅 2 位小数币种如 CNY）。minor<=0 时留空（金额未回填）。
+func formatMinor(minor int64) string {
+	if minor <= 0 {
+		return ""
+	}
+	return fmt.Sprintf("%d.%02d", minor/100, minor%100)
 }
 
 // signedPost 按契约对原始 body 签名后 POST 到 pay。
@@ -176,47 +206,6 @@ func (s *PayService) signedPost(path string, rawBody []byte) ([]byte, error) {
 	return body, nil
 }
 
-// productID 按 biz_code 查 pay 套餐 id（GET /api/v1/products，内存缓存 10 分钟）。
-func (s *PayService) productID(bizCode string) (int64, error) {
-	s.prodMu.Lock()
-	defer s.prodMu.Unlock()
-	if s.prodCache != nil && time.Since(s.prodAt) < 10*time.Minute {
-		if id, ok := s.prodCache[bizCode]; ok {
-			return id, nil
-		}
-	}
-	resp, err := s.client.Get(s.baseURL + "/api/v1/products")
-	if err != nil {
-		return 0, err
-	}
-	defer resp.Body.Close()
-	body, _ := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
-	if resp.StatusCode != http.StatusOK {
-		return 0, fmt.Errorf("pay HTTP %d", resp.StatusCode)
-	}
-	var pr struct {
-		Data []struct {
-			ID      int64  `json:"id"`
-			BizCode string `json:"biz_code"`
-		} `json:"data"`
-	}
-	if err := json.Unmarshal(body, &pr); err != nil {
-		return 0, err
-	}
-	cache := make(map[string]int64, len(pr.Data))
-	for _, p := range pr.Data {
-		if p.BizCode != "" {
-			cache[p.BizCode] = p.ID
-		}
-	}
-	s.prodCache, s.prodAt = cache, time.Now()
-	id, ok := cache[bizCode]
-	if !ok {
-		return 0, fmt.Errorf("pay 侧无 biz_code=%s 的套餐", bizCode)
-	}
-	return id, nil
-}
-
 // ---------- ② webhook 入账 ----------
 
 type payNotification struct {
@@ -426,6 +415,8 @@ type PurchaseStatus struct {
 	Status      string     `json:"status"`
 	BizCode     string     `json:"product_biz_code"`
 	Amount      string     `json:"amount"`
+	AmountMinor int64      `json:"amount_minor"`
+	Currency    string     `json:"currency"`
 	PaidAt      *time.Time `json:"paid_at,omitempty"`
 	ExpiresAt   *time.Time `json:"expires_at,omitempty"` // 续期后的门店授权到期时间
 }
@@ -438,7 +429,14 @@ func (s *PayService) Status(shopID uint64, outTradeNo string) (*PurchaseStatus,
 		}
 		return nil, err
 	}
-	st := &PurchaseStatus{OutTradeNo: p.OutTradeNo, Status: p.Status, BizCode: p.ProductBizCode, Amount: p.Amount, PaidAt: p.PaidAt}
+	amount := formatMinor(p.AmountMinor)
+	if amount == "" {
+		amount = p.Amount // 残单回退：v1 遗留/查单未回填时用旧列
+	}
+	st := &PurchaseStatus{
+		OutTradeNo: p.OutTradeNo, Status: p.Status, BizCode: p.ProductBizCode,
+		Amount: amount, AmountMinor: p.AmountMinor, Currency: p.Currency, PaidAt: p.PaidAt,
+	}
 	if p.Status == "paid" {
 		var lic model.License
 		if err := s.db.Where("shop_id = ? AND is_active = ?", shopID, true).
@@ -487,13 +485,15 @@ func (s *PayService) reconcileOnce() {
 		if err != nil {
 			continue
 		}
+		// 状态语义暂沿用旧的三态判断（v2 八态 created|pending|paid|canceled|expired|
+		// refunding|partially_refunded|refunded 的完整适配留 Task 4）；这里仅做字段对齐保编译。
 		switch st.Status {
 		case "paid":
 			paidAt := time.Now()
 			if st.PaidAt != nil {
 				paidAt = *st.PaidAt
 			}
-			if err := s.settle(p.OutTradeNo, p.ProductBizCode, st.Amount, st.TradeNo, "", paidAt); err != nil {
+			if err := s.settle(p.OutTradeNo, p.ProductBizCode, formatMinor(st.AmountMinor), "", "", paidAt); err != nil {
 				log.Printf("[pay] reconcile settle failed out_trade_no=%s: %v", p.OutTradeNo, err)
 			} else {
 				log.Printf("[pay] reconcile settled out_trade_no=%s (webhook missed)", p.OutTradeNo)
@@ -508,17 +508,21 @@ func (s *PayService) reconcileOnce() {
 	}
 }
 
+// payOrderStatus 查单响应（pay v2 契约，GET /api/v2/orders/:order_no，无鉴权）。
+// 不回传 biz_ref/trade_no。status 八态：created|pending|paid|canceled|expired|
+// refunding|partially_refunded|refunded。
 type payOrderStatus struct {
-	OutTradeNo string     `json:"out_trade_no"`
+	OrderNo     string     `json:"order_no"`
-	Amount     string     `json:"amount"`
+	Status      string     `json:"status"`
-	Status     string     `json:"status"` // pending | paid | closed | refunded
+	Subject     string     `json:"subject"`
-	TradeNo    string     `json:"trade_no"`
+	AmountMinor int64      `json:"amount_minor"`
+	Currency    string     `json:"currency"`
 	PaidAt      *time.Time `json:"paid_at"`
 }
 
 // queryOrder 查单（契约未要求签名头）。
-func (s *PayService) queryOrder(outTradeNo string) (*payOrderStatus, error) {
+func (s *PayService) queryOrder(orderNo string) (*payOrderStatus, error) {
-	resp, err := s.client.Get(s.baseURL + "/api/v1/orders/" + outTradeNo)
+	resp, err := s.client.Get(s.baseURL + "/api/v2/orders/" + orderNo)
 	if err != nil {
 		return nil, err
 	}

backend/internal/service/pay_test.go

@@ -229,13 +229,10 @@ func TestCreatePurchase_HappyPath(t *testing.T) {
 	db := testutil.SetupTestDB()
 	shop := testutil.CreateTestShop(db, "PAY006")
 
-	// 假 pay 服务：/products 列表 + /orders 验签后返回 pay_url
+	// 假 pay v2 服务：POST /api/v2/orders 验签后返回 session（redirect）+ GET /api/v2/orders/:no 回填金额
 	mux := http.NewServeMux()
-	mux.HandleFunc("GET /api/v1/products", func(w http.ResponseWriter, r *http.Request) {
+	var gotSku, gotMethod, gotBizSystem, gotBizRef string
-		fmt.Fprint(w, `{"data":[{"id":3,"biz_code":"annual_standard"},{"id":4,"biz_code":"monthly_pro"}]}`)
+	mux.HandleFunc("POST /api/v2/orders", func(w http.ResponseWriter, r *http.Request) {
-	})
-	var gotBizRef, gotClientType string
-	mux.HandleFunc("POST /api/v1/orders", func(w http.ResponseWriter, r *http.Request) {
 		body := make([]byte, r.ContentLength)
 		_, _ = r.Body.Read(body)
 		if !util.PaySignVerify(testPaySecret, r.Header.Get("X-Pay-Sign"),
@@ -245,9 +242,14 @@ func TestCreatePurchase_HappyPath(t *testing.T) {
 		}
 		var req map[string]any
 		_ = json.Unmarshal(body, &req)
+		gotSku, _ = req["sku"].(string)
+		gotMethod, _ = req["method"].(string)
+		gotBizSystem, _ = req["biz_system"].(string)
 		gotBizRef, _ = req["biz_ref"].(string)
-		gotClientType, _ = req["client_type"].(string)
+		fmt.Fprint(w, `{"data":{"order_no":"pay-x1","session":{"render_type":"redirect","payload":{"url":"https://pay.test/cashier"},"expires_at":"2026-07-10T12:00:00Z"}}}`)
-		fmt.Fprint(w, `{"data":{"pay_url":"https://openapi.alipay.com/gateway","out_trade_no":"yanmei-new-1","amount":"2999.00","subject":"年付标准"}}`)
+	})
+	mux.HandleFunc("GET /api/v2/orders/pay-x1", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprint(w, `{"data":{"order_no":"pay-x1","status":"pending","subject":"岩美酒库·标准版年付","amount_minor":299900,"currency":"CNY"}}`)
 	})
 	payServer := httptest.NewServer(mux)
 	defer payServer.Close()
@@ -255,15 +257,25 @@ func TestCreatePurchase_HappyPath(t *testing.T) {
 	svc := newTestPaySvc(db, payServer.URL)
 	res, err := svc.CreatePurchase(shop.ID, 1, "annual_standard", "mobile")
 	require.NoError(t, err)
-	assert.Equal(t, "https://openapi.alipay.com/gateway", res.PayURL)
+	assert.Equal(t, "pay-x1", res.OutTradeNo)
-	assert.Equal(t, "yanmei-new-1", res.OutTradeNo)
+	assert.Equal(t, "redirect", res.RenderType)
+	assert.Equal(t, "https://pay.test/cashier", res.Payload["url"])
+	assert.Equal(t, int64(299900), res.AmountMinor)
+	assert.Equal(t, "CNY", res.Currency)
+	assert.Equal(t, "https://pay.test/cashier", res.PayURL, "兼容字段：redirect 时 = payload.url")
+	assert.Equal(t, "2999.00", res.Amount, "兼容字段：分转元字符串")
+
+	assert.Equal(t, "annual_standard", gotSku, "sku 应直用 biz_code")
+	assert.Equal(t, "alipay", gotMethod)
+	assert.Equal(t, "jiu", gotBizSystem)
 
 	var p model.LicensePurchase
-	require.NoError(t, db.Where("out_trade_no = ?", "yanmei-new-1").First(&p).Error)
+	require.NoError(t, db.Where("out_trade_no = ?", "pay-x1").First(&p).Error)
 	assert.Equal(t, "pending", p.Status)
-	assert.Equal(t, "2999.00", p.Amount)
+	assert.Equal(t, int64(299900), p.AmountMinor)
+	assert.Equal(t, "CNY", p.Currency)
+	assert.Equal(t, "https://pay.test/cashier", p.PayURL)
 	assert.Equal(t, strconv.FormatUint(p.ID, 10), gotBizRef, "biz_ref 应为购买记录 id")
-	assert.Equal(t, "mobile", gotClientType, "client_type 应透传给 pay（契约 v1.1.0）")
 }
 
 func TestCreatePurchase_UnknownPlanAndUnconfigured(t *testing.T) {