feat: 支持用户专属分组倍率配置

backend/cmd/server/wire_gen.go

@@ -59,8 +59,9 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	billingCacheService := service.NewBillingCacheService(billingCache, userRepository, userSubscriptionRepository, configConfig)
 	apiKeyRepository := repository.NewAPIKeyRepository(client)
 	groupRepository := repository.NewGroupRepository(client, db)
+	userGroupRateRepository := repository.NewUserGroupRateRepository(db)
 	apiKeyCache := repository.NewAPIKeyCache(redisClient)
-	apiKeyService := service.NewAPIKeyService(apiKeyRepository, userRepository, groupRepository, userSubscriptionRepository, apiKeyCache, configConfig)
+	apiKeyService := service.NewAPIKeyService(apiKeyRepository, userRepository, groupRepository, userSubscriptionRepository, userGroupRateRepository, apiKeyCache, configConfig)
 	apiKeyAuthCacheInvalidator := service.ProvideAPIKeyAuthCacheInvalidator(apiKeyService)
 	promoService := service.NewPromoService(promoCodeRepository, userRepository, billingCacheService, client, apiKeyAuthCacheInvalidator)
 	authService := service.NewAuthService(userRepository, redeemCodeRepository, refreshTokenCache, configConfig, settingService, emailService, turnstileService, emailQueueService, promoService)
@@ -100,7 +101,7 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	proxyRepository := repository.NewProxyRepository(client, db)
 	proxyExitInfoProber := repository.NewProxyExitInfoProber(configConfig)
 	proxyLatencyCache := repository.NewProxyLatencyCache(redisClient)
-	adminService := service.NewAdminService(userRepository, groupRepository, accountRepository, proxyRepository, apiKeyRepository, redeemCodeRepository, billingCacheService, proxyExitInfoProber, proxyLatencyCache, apiKeyAuthCacheInvalidator)
+	adminService := service.NewAdminService(userRepository, groupRepository, accountRepository, proxyRepository, apiKeyRepository, redeemCodeRepository, userGroupRateRepository, billingCacheService, proxyExitInfoProber, proxyLatencyCache, apiKeyAuthCacheInvalidator)
 	adminUserHandler := admin.NewUserHandler(adminService)
 	groupHandler := admin.NewGroupHandler(adminService)
 	claudeOAuthClient := repository.NewClaudeOAuthClient()
@@ -153,7 +154,7 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	identityService := service.NewIdentityService(identityCache)
 	deferredService := service.ProvideDeferredService(accountRepository, timingWheelService)
 	claudeTokenProvider := service.NewClaudeTokenProvider(accountRepository, geminiTokenCache, oAuthService)
-	gatewayService := service.NewGatewayService(accountRepository, groupRepository, usageLogRepository, userRepository, userSubscriptionRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, identityService, httpUpstream, deferredService, claudeTokenProvider, sessionLimitCache)
+	gatewayService := service.NewGatewayService(accountRepository, groupRepository, usageLogRepository, userRepository, userSubscriptionRepository, userGroupRateRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, identityService, httpUpstream, deferredService, claudeTokenProvider, sessionLimitCache)
 	openAITokenProvider := service.NewOpenAITokenProvider(accountRepository, geminiTokenCache, openAIOAuthService)
 	openAIGatewayService := service.NewOpenAIGatewayService(accountRepository, usageLogRepository, userRepository, userSubscriptionRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, httpUpstream, deferredService, openAITokenProvider)
 	geminiMessagesCompatService := service.NewGeminiMessagesCompatService(accountRepository, groupRepository, gatewayCache, schedulerSnapshotService, geminiTokenProvider, rateLimitService, httpUpstream, antigravityGatewayService, configConfig)

backend/go.sum

@@ -170,6 +170,8 @@ github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovk
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-runewidth v0.0.15 h1:UNAjwbU9l54TA3KzvqLGxwWjHmMgBUVhBiTjelZgg3U=
+github.com/mattn/go-runewidth v0.0.15/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/mattn/go-sqlite3 v1.14.17 h1:mCRHCLDUBXgpKAqIKsaAaAsrAlbkeomtRFKXh2L6YIM=
 github.com/mattn/go-sqlite3 v1.14.17/go.mod h1:2eHXhiwb8IkHr+BDWZGa96P6+rkvnG63S2DGjv9HUNg=
 github.com/mdelapenya/tlscert v0.2.0 h1:7H81W6Z/4weDvZBNOfQte5GpIMo0lGYEeWbkGp5LJHI=
@@ -203,6 +205,8 @@ github.com/morikuni/aec v1.0.0 h1:nP9CBfwrvYnBRgY6qfDQkygYDmYwOilePFkwzv4dU8A=
 github.com/morikuni/aec v1.0.0/go.mod h1:BbKIizmSmc5MMPqRYbxO4ZU0S0+P200+tUnFx7PXmsc=
 github.com/ncruces/go-strftime v1.0.0 h1:HMFp8mLCTPp341M/ZnA4qaf7ZlsbTc+miZjCLOFAw7w=
 github.com/ncruces/go-strftime v1.0.0/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
+github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
+github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
 github.com/opencontainers/go-digest v1.0.0 h1:apOUWs51W5PlhuyGyz9FCeeBIOUDA/6nW8Oi/yOhh5U=
 github.com/opencontainers/go-digest v1.0.0/go.mod h1:0JzlMkj0TRzQZfJkVvzbP0HBR3IKzErnv2BNG4W4MAM=
 github.com/opencontainers/image-spec v1.1.1 h1:y0fUlFfIZhPF1W537XOLg0/fcx6zcHCJwooC2xJA040=
@@ -230,6 +234,8 @@ github.com/refraction-networking/utls v1.8.1 h1:yNY1kapmQU8JeM1sSw2H2asfTIwWxIkr
 github.com/refraction-networking/utls v1.8.1/go.mod h1:jkSOEkLqn+S/jtpEHPOsVv/4V4EVnelwbMQl4vCWXAM=
 github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec h1:W09IVJc94icq4NjY3clb7Lk8O1qJ8BdBEF8z0ibU0rE=
 github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec/go.mod h1:qqbHyh8v60DhA7CoWK5oRCqLrMHRGoxYCSS9EjAz6Eo=
+github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
+github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
 github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzGIFLtro=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
@@ -252,6 +258,8 @@ github.com/spf13/afero v1.11.0 h1:WJQKhtpdm3v2IzqG8VMqrr6Rf3UYpEF239Jy9wNepM8=
 github.com/spf13/afero v1.11.0/go.mod h1:GH9Y3pIexgf1MTIWtNGyogA5MwRIDXGUr+hbWNoBjkY=
 github.com/spf13/cast v1.6.0 h1:GEiTHELF+vaR5dhz3VqZfFSzZjYbgeKDpBxQVS4GYJ0=
 github.com/spf13/cast v1.6.0/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
+github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
+github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spf13/viper v1.18.2 h1:LUXCnvUvSM6FXAsj6nnfc8Q2tp1dIgUfY9Kc8GsSOiQ=

backend/internal/handler/admin/user_handler.go

@@ -45,6 +45,9 @@ type UpdateUserRequest struct {
 	Concurrency   *int     `json:"concurrency"`
 	Status        string   `json:"status" binding:"omitempty,oneof=active disabled"`
 	AllowedGroups *[]int64 `json:"allowed_groups"`
+	// GroupRates 用户专属分组倍率配置
+	// map[groupID]*rate，nil 表示删除该分组的专属倍率
+	GroupRates map[int64]*float64 `json:"group_rates"`
 }
 
 // UpdateBalanceRequest represents balance update request
@@ -183,6 +186,7 @@ func (h *UserHandler) Update(c *gin.Context) {
 		Concurrency:   req.Concurrency,
 		Status:        req.Status,
 		AllowedGroups: req.AllowedGroups,
+		GroupRates:    req.GroupRates,
 	})
 	if err != nil {
 		response.ErrorFrom(c, err)

backend/internal/handler/api_key_handler.go

@@ -243,3 +243,21 @@ func (h *APIKeyHandler) GetAvailableGroups(c *gin.Context) {
 	}
 	response.Success(c, out)
 }
+
+// GetUserGroupRates 获取当前用户的专属分组倍率配置
+// GET /api/v1/groups/rates
+func (h *APIKeyHandler) GetUserGroupRates(c *gin.Context) {
+	subject, ok := middleware2.GetAuthSubjectFromContext(c)
+	if !ok {
+		response.Unauthorized(c, "User not authenticated")
+		return
+	}
+
+	rates, err := h.apiKeyService.GetUserGroupRates(c.Request.Context(), subject.UserID)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	response.Success(c, rates)
+}

backend/internal/handler/dto/mappers.go

@@ -58,8 +58,9 @@ func UserFromServiceAdmin(u *service.User) *AdminUser {
 		return nil
 	}
 	return &AdminUser{
-		User:  *base,
-		Notes: u.Notes,
+		User:       *base,
+		Notes:      u.Notes,
+		GroupRates: u.GroupRates,
 	}
 }
 

backend/internal/handler/dto/types.go

@@ -29,6 +29,9 @@ type AdminUser struct {
 	User
 
 	Notes string `json:"notes"`
+	// GroupRates 用户专属分组倍率配置
+	// map[groupID]rateMultiplier
+	GroupRates map[int64]float64 `json:"group_rates,omitempty"`
 }
 
 type APIKey struct {

backend/internal/repository/user_group_rate_repo.go

+package repository
+
+import (
+	"context"
+	"database/sql"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+)
+
+type userGroupRateRepository struct {
+	sql sqlExecutor
+}
+
+// NewUserGroupRateRepository 创建用户专属分组倍率仓储
+func NewUserGroupRateRepository(sqlDB *sql.DB) service.UserGroupRateRepository {
+	return &userGroupRateRepository{sql: sqlDB}
+}
+
+// GetByUserID 获取用户的所有专属分组倍率
+func (r *userGroupRateRepository) GetByUserID(ctx context.Context, userID int64) (map[int64]float64, error) {
+	query := `SELECT group_id, rate_multiplier FROM user_group_rate_multipliers WHERE user_id = $1`
+	rows, err := r.sql.QueryContext(ctx, query, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer func() { _ = rows.Close() }()
+
+	result := make(map[int64]float64)
+	for rows.Next() {
+		var groupID int64
+		var rate float64
+		if err := rows.Scan(&groupID, &rate); err != nil {
+			return nil, err
+		}
+		result[groupID] = rate
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return result, nil
+}
+
+// GetByUserAndGroup 获取用户在特定分组的专属倍率
+func (r *userGroupRateRepository) GetByUserAndGroup(ctx context.Context, userID, groupID int64) (*float64, error) {
+	query := `SELECT rate_multiplier FROM user_group_rate_multipliers WHERE user_id = $1 AND group_id = $2`
+	var rate float64
+	err := scanSingleRow(ctx, r.sql, query, []any{userID, groupID}, &rate)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &rate, nil
+}
+
+// SyncUserGroupRates 同步用户的分组专属倍率
+func (r *userGroupRateRepository) SyncUserGroupRates(ctx context.Context, userID int64, rates map[int64]*float64) error {
+	if len(rates) == 0 {
+		// 如果传入空 map，删除该用户的所有专属倍率
+		_, err := r.sql.ExecContext(ctx, `DELETE FROM user_group_rate_multipliers WHERE user_id = $1`, userID)
+		return err
+	}
+
+	// 分离需要删除和需要 upsert 的记录
+	var toDelete []int64
+	toUpsert := make(map[int64]float64)
+	for groupID, rate := range rates {
+		if rate == nil {
+			toDelete = append(toDelete, groupID)
+		} else {
+			toUpsert[groupID] = *rate
+		}
+	}
+
+	// 删除指定的记录
+	for _, groupID := range toDelete {
+		_, err := r.sql.ExecContext(ctx,
+			`DELETE FROM user_group_rate_multipliers WHERE user_id = $1 AND group_id = $2`,
+			userID, groupID)
+		if err != nil {
+			return err
+		}
+	}
+
+	// Upsert 记录
+	now := time.Now()
+	for groupID, rate := range toUpsert {
+		_, err := r.sql.ExecContext(ctx, `
+			INSERT INTO user_group_rate_multipliers (user_id, group_id, rate_multiplier, created_at, updated_at)
+			VALUES ($1, $2, $3, $4, $4)
+			ON CONFLICT (user_id, group_id) DO UPDATE SET rate_multiplier = $3, updated_at = $4
+		`, userID, groupID, rate, now)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// DeleteByGroupID 删除指定分组的所有用户专属倍率
+func (r *userGroupRateRepository) DeleteByGroupID(ctx context.Context, groupID int64) error {
+	_, err := r.sql.ExecContext(ctx, `DELETE FROM user_group_rate_multipliers WHERE group_id = $1`, groupID)
+	return err
+}
+
+// DeleteByUserID 删除指定用户的所有专属倍率
+func (r *userGroupRateRepository) DeleteByUserID(ctx context.Context, userID int64) error {
+	_, err := r.sql.ExecContext(ctx, `DELETE FROM user_group_rate_multipliers WHERE user_id = $1`, userID)
+	return err
+}

backend/internal/repository/wire.go

@@ -66,6 +66,7 @@ var ProviderSet = wire.NewSet(
 	NewUserSubscriptionRepository,
 	NewUserAttributeDefinitionRepository,
 	NewUserAttributeValueRepository,
+	NewUserGroupRateRepository,
 
 	// Cache implementations
 	NewGatewayCache,

backend/internal/server/api_contract_test.go

@@ -593,7 +593,7 @@ func newContractDeps(t *testing.T) *contractDeps {
 	}
 
 	userService := service.NewUserService(userRepo, nil)
-	apiKeyService := service.NewAPIKeyService(apiKeyRepo, userRepo, groupRepo, userSubRepo, apiKeyCache, cfg)
+	apiKeyService := service.NewAPIKeyService(apiKeyRepo, userRepo, groupRepo, userSubRepo, nil, apiKeyCache, cfg)
 
 	usageRepo := newStubUsageLogRepo()
 	usageService := service.NewUsageService(usageRepo, userRepo, nil, nil)
@@ -607,7 +607,7 @@ func newContractDeps(t *testing.T) *contractDeps {
 	settingRepo := newStubSettingRepo()
 	settingService := service.NewSettingService(settingRepo, cfg)
 
-	adminService := service.NewAdminService(userRepo, groupRepo, &accountRepo, proxyRepo, apiKeyRepo, redeemRepo, nil, nil, nil, nil)
+	adminService := service.NewAdminService(userRepo, groupRepo, &accountRepo, proxyRepo, apiKeyRepo, redeemRepo, nil, nil, nil, nil, nil)
 	authHandler := handler.NewAuthHandler(cfg, nil, userService, settingService, nil, redeemService, nil)
 	apiKeyHandler := handler.NewAPIKeyHandler(apiKeyService)
 	usageHandler := handler.NewUsageHandler(usageService, apiKeyService)

backend/internal/server/middleware/api_key_auth_google_test.go

@@ -93,6 +93,7 @@ func newTestAPIKeyService(repo service.APIKeyRepository) *service.APIKeyService
 		nil, // userRepo (unused in GetByKey)
 		nil, // groupRepo
 		nil, // userSubRepo
+		nil, // userGroupRateRepo
 		nil, // cache
 		&config.Config{},
 	)
@@ -187,6 +188,7 @@ func TestApiKeyAuthWithSubscriptionGoogleSetsGroupContext(t *testing.T) {
 		nil,
 		nil,
 		nil,
+		nil,
 		&config.Config{RunMode: config.RunModeSimple},
 	)
 

backend/internal/server/middleware/api_key_auth_test.go

@@ -59,7 +59,7 @@ func TestSimpleModeBypassesQuotaCheck(t *testing.T) {
 
 	t.Run("simple_mode_bypasses_quota_check", func(t *testing.T) {
 		cfg := &config.Config{RunMode: config.RunModeSimple}
-		apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, cfg)
+		apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, nil, cfg)
 		subscriptionService := service.NewSubscriptionService(nil, &stubUserSubscriptionRepo{}, nil)
 		router := newAuthTestRouter(apiKeyService, subscriptionService, cfg)
 
@@ -73,7 +73,7 @@ func TestSimpleModeBypassesQuotaCheck(t *testing.T) {
 
 	t.Run("standard_mode_enforces_quota_check", func(t *testing.T) {
 		cfg := &config.Config{RunMode: config.RunModeStandard}
-		apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, cfg)
+		apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, nil, cfg)
 
 		now := time.Now()
 		sub := &service.UserSubscription{
@@ -150,7 +150,7 @@ func TestAPIKeyAuthSetsGroupContext(t *testing.T) {
 	}
 
 	cfg := &config.Config{RunMode: config.RunModeSimple}
-	apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, cfg)
+	apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, nil, cfg)
 	router := gin.New()
 	router.Use(gin.HandlerFunc(NewAPIKeyAuthMiddleware(apiKeyService, nil, cfg)))
 	router.GET("/t", func(c *gin.Context) {
@@ -208,7 +208,7 @@ func TestAPIKeyAuthOverwritesInvalidContextGroup(t *testing.T) {
 	}
 
 	cfg := &config.Config{RunMode: config.RunModeSimple}
-	apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, cfg)
+	apiKeyService := service.NewAPIKeyService(apiKeyRepo, nil, nil, nil, nil, nil, cfg)
 	router := gin.New()
 	router.Use(gin.HandlerFunc(NewAPIKeyAuthMiddleware(apiKeyService, nil, cfg)))
 

backend/internal/server/routes/user.go

@@ -49,6 +49,7 @@ func RegisterUserRoutes(
 		groups := authenticated.Group("/groups")
 		{
 			groups.GET("/available", h.APIKey.GetAvailableGroups)
+			groups.GET("/rates", h.APIKey.GetUserGroupRates)
 		}
 
 		// 使用记录

backend/internal/service/admin_service.go

@@ -93,6 +93,9 @@ type UpdateUserInput struct {
 	Concurrency   *int     // 使用指针区分"未提供"和"设置为0"
 	Status        string
 	AllowedGroups *[]int64 // 使用指针区分"未提供"和"设置为空数组"
+	// GroupRates 用户专属分组倍率配置
+	// map[groupID]*rate，nil 表示删除该分组的专属倍率
+	GroupRates map[int64]*float64
 }
 
 type CreateGroupInput struct {
@@ -293,6 +296,7 @@ type adminServiceImpl struct {
 	proxyRepo            ProxyRepository
 	apiKeyRepo           APIKeyRepository
 	redeemCodeRepo       RedeemCodeRepository
+	userGroupRateRepo    UserGroupRateRepository
 	billingCacheService  *BillingCacheService
 	proxyProber          ProxyExitInfoProber
 	proxyLatencyCache    ProxyLatencyCache
@@ -307,6 +311,7 @@ func NewAdminService(
 	proxyRepo ProxyRepository,
 	apiKeyRepo APIKeyRepository,
 	redeemCodeRepo RedeemCodeRepository,
+	userGroupRateRepo UserGroupRateRepository,
 	billingCacheService *BillingCacheService,
 	proxyProber ProxyExitInfoProber,
 	proxyLatencyCache ProxyLatencyCache,
@@ -319,6 +324,7 @@ func NewAdminService(
 		proxyRepo:            proxyRepo,
 		apiKeyRepo:           apiKeyRepo,
 		redeemCodeRepo:       redeemCodeRepo,
+		userGroupRateRepo:    userGroupRateRepo,
 		billingCacheService:  billingCacheService,
 		proxyProber:          proxyProber,
 		proxyLatencyCache:    proxyLatencyCache,
@@ -333,11 +339,35 @@ func (s *adminServiceImpl) ListUsers(ctx context.Context, page, pageSize int, fi
 	if err != nil {
 		return nil, 0, err
 	}
+	// 批量加载用户专属分组倍率
+	if s.userGroupRateRepo != nil && len(users) > 0 {
+		for i := range users {
+			rates, err := s.userGroupRateRepo.GetByUserID(ctx, users[i].ID)
+			if err != nil {
+				log.Printf("failed to load user group rates: user_id=%d err=%v", users[i].ID, err)
+				continue
+			}
+			users[i].GroupRates = rates
+		}
+	}
 	return users, result.Total, nil
 }
 
 func (s *adminServiceImpl) GetUser(ctx context.Context, id int64) (*User, error) {
-	return s.userRepo.GetByID(ctx, id)
+	user, err := s.userRepo.GetByID(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+	// 加载用户专属分组倍率
+	if s.userGroupRateRepo != nil {
+		rates, err := s.userGroupRateRepo.GetByUserID(ctx, id)
+		if err != nil {
+			log.Printf("failed to load user group rates: user_id=%d err=%v", id, err)
+		} else {
+			user.GroupRates = rates
+		}
+	}
+	return user, nil
 }
 
 func (s *adminServiceImpl) CreateUser(ctx context.Context, input *CreateUserInput) (*User, error) {
@@ -406,6 +436,14 @@ func (s *adminServiceImpl) UpdateUser(ctx context.Context, id int64, input *Upda
 	if err := s.userRepo.Update(ctx, user); err != nil {
 		return nil, err
 	}
+
+	// 同步用户专属分组倍率
+	if input.GroupRates != nil && s.userGroupRateRepo != nil {
+		if err := s.userGroupRateRepo.SyncUserGroupRates(ctx, user.ID, input.GroupRates); err != nil {
+			log.Printf("failed to sync user group rates: user_id=%d err=%v", user.ID, err)
+		}
+	}
+
 	if s.authCacheInvalidator != nil {
 		if user.Concurrency != oldConcurrency || user.Status != oldStatus || user.Role != oldRole {
 			s.authCacheInvalidator.InvalidateAuthCacheByUserID(ctx, user.ID)
@@ -941,6 +979,7 @@ func (s *adminServiceImpl) DeleteGroup(ctx context.Context, id int64) error {
 	if err != nil {
 		return err
 	}
+	// 注意：user_group_rate_multipliers 表通过外键 ON DELETE CASCADE 自动清理
 
 	// 事务成功后，异步失效受影响用户的订阅缓存
 	if len(affectedUserIDs) > 0 && s.billingCacheService != nil {

backend/internal/service/api_key_service.go

@@ -115,15 +115,16 @@ type UpdateAPIKeyRequest struct {
 
 // APIKeyService API Key服务
 type APIKeyService struct {
-	apiKeyRepo  APIKeyRepository
-	userRepo    UserRepository
-	groupRepo   GroupRepository
-	userSubRepo UserSubscriptionRepository
-	cache       APIKeyCache
-	cfg         *config.Config
-	authCacheL1 *ristretto.Cache
-	authCfg     apiKeyAuthCacheConfig
-	authGroup   singleflight.Group
+	apiKeyRepo        APIKeyRepository
+	userRepo          UserRepository
+	groupRepo         GroupRepository
+	userSubRepo       UserSubscriptionRepository
+	userGroupRateRepo UserGroupRateRepository
+	cache             APIKeyCache
+	cfg               *config.Config
+	authCacheL1       *ristretto.Cache
+	authCfg           apiKeyAuthCacheConfig
+	authGroup         singleflight.Group
 }
 
 // NewAPIKeyService 创建API Key服务实例
@@ -132,16 +133,18 @@ func NewAPIKeyService(
 	userRepo UserRepository,
 	groupRepo GroupRepository,
 	userSubRepo UserSubscriptionRepository,
+	userGroupRateRepo UserGroupRateRepository,
 	cache APIKeyCache,
 	cfg *config.Config,
 ) *APIKeyService {
 	svc := &APIKeyService{
-		apiKeyRepo:  apiKeyRepo,
-		userRepo:    userRepo,
-		groupRepo:   groupRepo,
-		userSubRepo: userSubRepo,
-		cache:       cache,
-		cfg:         cfg,
+		apiKeyRepo:        apiKeyRepo,
+		userRepo:          userRepo,
+		groupRepo:         groupRepo,
+		userSubRepo:       userSubRepo,
+		userGroupRateRepo: userGroupRateRepo,
+		cache:             cache,
+		cfg:               cfg,
 	}
 	svc.initAuthCache(cfg)
 	return svc
@@ -627,6 +630,19 @@ func (s *APIKeyService) SearchAPIKeys(ctx context.Context, userID int64, keyword
 	return keys, nil
 }
 
+// GetUserGroupRates 获取用户的专属分组倍率配置
+// 返回 map[groupID]rateMultiplier
+func (s *APIKeyService) GetUserGroupRates(ctx context.Context, userID int64) (map[int64]float64, error) {
+	if s.userGroupRateRepo == nil {
+		return nil, nil
+	}
+	rates, err := s.userGroupRateRepo.GetByUserID(ctx, userID)
+	if err != nil {
+		return nil, fmt.Errorf("get user group rates: %w", err)
+	}
+	return rates, nil
+}
+
 // CheckAPIKeyQuotaAndExpiry checks if the API key is valid for use (not expired, quota not exhausted)
 // Returns nil if valid, error if invalid
 func (s *APIKeyService) CheckAPIKeyQuotaAndExpiry(apiKey *APIKey) error {

backend/internal/service/api_key_service_cache_test.go

@@ -167,7 +167,7 @@ func TestAPIKeyService_GetByKey_UsesL2Cache(t *testing.T) {
 			NegativeTTLSeconds: 30,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 
 	groupID := int64(9)
 	cacheEntry := &APIKeyAuthCacheEntry{
@@ -223,7 +223,7 @@ func TestAPIKeyService_GetByKey_NegativeCache(t *testing.T) {
 			NegativeTTLSeconds: 30,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 	cache.getAuthCache = func(ctx context.Context, key string) (*APIKeyAuthCacheEntry, error) {
 		return &APIKeyAuthCacheEntry{NotFound: true}, nil
 	}
@@ -256,7 +256,7 @@ func TestAPIKeyService_GetByKey_CacheMissStoresL2(t *testing.T) {
 			NegativeTTLSeconds: 30,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 	cache.getAuthCache = func(ctx context.Context, key string) (*APIKeyAuthCacheEntry, error) {
 		return nil, redis.Nil
 	}
@@ -293,7 +293,7 @@ func TestAPIKeyService_GetByKey_UsesL1Cache(t *testing.T) {
 			L1TTLSeconds: 60,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 	require.NotNil(t, svc.authCacheL1)
 
 	_, err := svc.GetByKey(context.Background(), "k-l1")
@@ -320,7 +320,7 @@ func TestAPIKeyService_InvalidateAuthCacheByUserID(t *testing.T) {
 			NegativeTTLSeconds: 30,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 
 	svc.InvalidateAuthCacheByUserID(context.Background(), 7)
 	require.Len(t, cache.deleteAuthKeys, 2)
@@ -338,7 +338,7 @@ func TestAPIKeyService_InvalidateAuthCacheByGroupID(t *testing.T) {
 			L2TTLSeconds: 60,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 
 	svc.InvalidateAuthCacheByGroupID(context.Background(), 9)
 	require.Len(t, cache.deleteAuthKeys, 2)
@@ -356,7 +356,7 @@ func TestAPIKeyService_InvalidateAuthCacheByKey(t *testing.T) {
 			L2TTLSeconds: 60,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 
 	svc.InvalidateAuthCacheByKey(context.Background(), "k1")
 	require.Len(t, cache.deleteAuthKeys, 1)
@@ -375,7 +375,7 @@ func TestAPIKeyService_GetByKey_CachesNegativeOnRepoMiss(t *testing.T) {
 			NegativeTTLSeconds: 30,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 	cache.getAuthCache = func(ctx context.Context, key string) (*APIKeyAuthCacheEntry, error) {
 		return nil, redis.Nil
 	}
@@ -411,7 +411,7 @@ func TestAPIKeyService_GetByKey_SingleflightCollapses(t *testing.T) {
 			Singleflight: true,
 		},
 	}
-	svc := NewAPIKeyService(repo, nil, nil, nil, cache, cfg)
+	svc := NewAPIKeyService(repo, nil, nil, nil, nil, cache, cfg)
 
 	start := make(chan struct{})
 	wg := sync.WaitGroup{}

backend/internal/service/gateway_service.go

@@ -384,6 +384,7 @@ type GatewayService struct {
 	usageLogRepo        UsageLogRepository
 	userRepo            UserRepository
 	userSubRepo         UserSubscriptionRepository
+	userGroupRateRepo   UserGroupRateRepository
 	cache               GatewayCache
 	cfg                 *config.Config
 	schedulerSnapshot   *SchedulerSnapshotService
@@ -405,6 +406,7 @@ func NewGatewayService(
 	usageLogRepo UsageLogRepository,
 	userRepo UserRepository,
 	userSubRepo UserSubscriptionRepository,
+	userGroupRateRepo UserGroupRateRepository,
 	cache GatewayCache,
 	cfg *config.Config,
 	schedulerSnapshot *SchedulerSnapshotService,
@@ -424,6 +426,7 @@ func NewGatewayService(
 		usageLogRepo:        usageLogRepo,
 		userRepo:            userRepo,
 		userSubRepo:         userSubRepo,
+		userGroupRateRepo:   userGroupRateRepo,
 		cache:               cache,
 		cfg:                 cfg,
 		schedulerSnapshot:   schedulerSnapshot,
@@ -4609,10 +4612,17 @@ func (s *GatewayService) RecordUsage(ctx context.Context, input *RecordUsageInpu
 	account := input.Account
 	subscription := input.Subscription
 
-	// 获取费率倍数
+	// 获取费率倍数（优先级：用户专属 > 分组默认 > 系统默认）
 	multiplier := s.cfg.Default.RateMultiplier
 	if apiKey.GroupID != nil && apiKey.Group != nil {
 		multiplier = apiKey.Group.RateMultiplier
+
+		// 检查用户专属倍率
+		if s.userGroupRateRepo != nil {
+			if userRate, err := s.userGroupRateRepo.GetByUserAndGroup(ctx, user.ID, *apiKey.GroupID); err == nil && userRate != nil {
+				multiplier = *userRate
+			}
+		}
 	}
 
 	var cost *CostBreakdown
@@ -4773,10 +4783,17 @@ func (s *GatewayService) RecordUsageWithLongContext(ctx context.Context, input *
 	account := input.Account
 	subscription := input.Subscription
 
-	// 获取费率倍数
+	// 获取费率倍数（优先级：用户专属 > 分组默认 > 系统默认）
 	multiplier := s.cfg.Default.RateMultiplier
 	if apiKey.GroupID != nil && apiKey.Group != nil {
 		multiplier = apiKey.Group.RateMultiplier
+
+		// 检查用户专属倍率
+		if s.userGroupRateRepo != nil {
+			if userRate, err := s.userGroupRateRepo.GetByUserAndGroup(ctx, user.ID, *apiKey.GroupID); err == nil && userRate != nil {
+				multiplier = *userRate
+			}
+		}
 	}
 
 	var cost *CostBreakdown

backend/internal/service/user.go

@@ -21,6 +21,10 @@ type User struct {
 	CreatedAt     time.Time
 	UpdatedAt     time.Time
 
+	// GroupRates 用户专属分组倍率配置
+	// map[groupID]rateMultiplier
+	GroupRates map[int64]float64
+
 	// TOTP 双因素认证字段
 	TotpSecretEncrypted *string    // AES-256-GCM 加密的 TOTP 密钥
 	TotpEnabled         bool       // 是否启用 TOTP
@@ -40,18 +44,20 @@ func (u *User) IsActive() bool {
 
 // CanBindGroup checks whether a user can bind to a given group.
 // For standard groups:
-// - If AllowedGroups is non-empty, only allow binding to IDs in that list.
-// - If AllowedGroups is empty (nil or length 0), allow binding to any non-exclusive group.
+// - Public groups (non-exclusive): all users can bind
+// - Exclusive groups: only users with the group in AllowedGroups can bind
 func (u *User) CanBindGroup(groupID int64, isExclusive bool) bool {
-	if len(u.AllowedGroups) > 0 {
-		for _, id := range u.AllowedGroups {
-			if id == groupID {
-				return true
-			}
+	// 公开分组（非专属）：所有用户都可以绑定
+	if !isExclusive {
+		return true
+	}
+	// 专属分组：需要在 AllowedGroups 中
+	for _, id := range u.AllowedGroups {
+		if id == groupID {
+			return true
 		}
-		return false
 	}
-	return !isExclusive
+	return false
 }
 
 func (u *User) SetPassword(password string) error {

backend/internal/service/user_group_rate.go

+package service
+
+import "context"
+
+// UserGroupRateRepository 用户专属分组倍率仓储接口
+// 允许管理员为特定用户设置分组的专属计费倍率，覆盖分组默认倍率
+type UserGroupRateRepository interface {
+	// GetByUserID 获取用户的所有专属分组倍率
+	// 返回 map[groupID]rateMultiplier
+	GetByUserID(ctx context.Context, userID int64) (map[int64]float64, error)
+
+	// GetByUserAndGroup 获取用户在特定分组的专属倍率
+	// 如果未设置专属倍率，返回 nil
+	GetByUserAndGroup(ctx context.Context, userID, groupID int64) (*float64, error)
+
+	// SyncUserGroupRates 同步用户的分组专属倍率
+	// rates: map[groupID]*rateMultiplier，nil 表示删除该分组的专属倍率
+	SyncUserGroupRates(ctx context.Context, userID int64, rates map[int64]*float64) error
+
+	// DeleteByGroupID 删除指定分组的所有用户专属倍率（分组删除时调用）
+	DeleteByGroupID(ctx context.Context, groupID int64) error
+
+	// DeleteByUserID 删除指定用户的所有专属倍率（用户删除时调用）
+	DeleteByUserID(ctx context.Context, userID int64) error
+}

backend/migrations/047_add_user_group_rate_multipliers.sql

+-- 用户专属分组倍率表
+-- 允许管理员为特定用户设置分组的专属计费倍率，覆盖分组默认倍率
+CREATE TABLE IF NOT EXISTS user_group_rate_multipliers (
+    user_id         BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    group_id        BIGINT NOT NULL REFERENCES groups(id) ON DELETE CASCADE,
+    rate_multiplier DECIMAL(10,4) NOT NULL,
+    created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    PRIMARY KEY (user_id, group_id)
+);
+
+-- 按 group_id 查询索引（删除分组时清理关联记录）
+CREATE INDEX IF NOT EXISTS idx_user_group_rate_multipliers_group_id
+    ON user_group_rate_multipliers(group_id);
+
+COMMENT ON TABLE user_group_rate_multipliers IS '用户专属分组倍率配置';
+COMMENT ON COLUMN user_group_rate_multipliers.user_id IS '用户ID';
+COMMENT ON COLUMN user_group_rate_multipliers.group_id IS '分组ID';
+COMMENT ON COLUMN user_group_rate_multipliers.rate_multiplier IS '专属计费倍率（覆盖分组默认倍率）';

frontend/src/api/groups.ts

@@ -18,8 +18,18 @@ export async function getAvailable(): Promise<Group[]> {
   return data
 }
 
+/**
+ * Get current user's custom group rate multipliers
+ * @returns Map of group_id to custom rate_multiplier
+ */
+export async function getUserGroupRates(): Promise<Record<number, number>> {
+  const { data } = await apiClient.get<Record<number, number> | null>('/groups/rates')
+  return data || {}
+}
+
 export const userGroupsAPI = {
-  getAvailable
+  getAvailable,
+  getUserGroupRates
 }
 
 export default userGroupsAPI