Merge pull request #706 from PMExtra/feat/default-subscriptions-on-user-create

feat(settings): add default subscriptions for new users

backend/cmd/jwtgen/main.go

@@ -33,7 +33,7 @@ func main() {
 	}()
 
 	userRepo := repository.NewUserRepository(client, sqlDB)
-	authService := service.NewAuthService(userRepo, nil, nil, cfg, nil, nil, nil, nil, nil)
+	authService := service.NewAuthService(userRepo, nil, nil, cfg, nil, nil, nil, nil, nil, nil)
 
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()

backend/cmd/server/wire_gen.go

@@ -48,7 +48,8 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	redisClient := repository.ProvideRedis(configConfig)
 	refreshTokenCache := repository.NewRefreshTokenCache(redisClient)
 	settingRepository := repository.NewSettingRepository(client)
-	settingService := service.NewSettingService(settingRepository, configConfig)
+	groupRepository := repository.NewGroupRepository(client, db)
+	settingService := service.ProvideSettingService(settingRepository, groupRepository, configConfig)
 	emailCache := repository.NewEmailCache(redisClient)
 	emailService := service.NewEmailService(settingRepository, emailCache)
 	turnstileVerifier := repository.NewTurnstileVerifier()
@@ -59,15 +60,14 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	userSubscriptionRepository := repository.NewUserSubscriptionRepository(client)
 	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, 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)
-	userService := service.NewUserService(userRepository, apiKeyAuthCacheInvalidator, billingCache)
 	subscriptionService := service.NewSubscriptionService(groupRepository, userSubscriptionRepository, billingCacheService, client, configConfig)
+	authService := service.NewAuthService(userRepository, redeemCodeRepository, refreshTokenCache, configConfig, settingService, emailService, turnstileService, emailQueueService, promoService, subscriptionService)
+	userService := service.NewUserService(userRepository, apiKeyAuthCacheInvalidator, billingCache)
 	redeemCache := repository.NewRedeemCache(redisClient)
 	redeemService := service.NewRedeemService(redeemCodeRepository, userRepository, subscriptionService, redeemCache, billingCacheService, client, apiKeyAuthCacheInvalidator)
 	secretEncryptor, err := repository.NewAESEncryptor(configConfig)
@@ -103,7 +103,7 @@ 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, soraAccountRepository, proxyRepository, apiKeyRepository, redeemCodeRepository, userGroupRateRepository, billingCacheService, proxyExitInfoProber, proxyLatencyCache, apiKeyAuthCacheInvalidator, client)
+	adminService := service.NewAdminService(userRepository, groupRepository, accountRepository, soraAccountRepository, proxyRepository, apiKeyRepository, redeemCodeRepository, userGroupRateRepository, billingCacheService, proxyExitInfoProber, proxyLatencyCache, apiKeyAuthCacheInvalidator, client, settingService, subscriptionService)
 	concurrencyCache := repository.ProvideConcurrencyCache(redisClient, configConfig)
 	concurrencyService := service.ProvideConcurrencyService(concurrencyCache, accountRepository, configConfig)
 	adminUserHandler := admin.NewUserHandler(adminService, concurrencyService)

backend/go.mod

@@ -180,6 +180,8 @@ require (
 	golang.org/x/text v0.34.0 // indirect
 	golang.org/x/tools v0.41.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20250929231259-57b25ae835d4 // indirect
+	google.golang.org/grpc v1.75.1 // indirect
+	google.golang.org/protobuf v1.36.10 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	modernc.org/libc v1.67.6 // indirect
 	modernc.org/mathutil v1.7.1 // indirect

backend/internal/handler/admin/setting_handler.go

@@ -51,6 +51,13 @@ func (h *SettingHandler) GetSettings(c *gin.Context) {
 
 	// Check if ops monitoring is enabled (respects config.ops.enabled)
 	opsEnabled := h.opsService != nil && h.opsService.IsMonitoringEnabled(c.Request.Context())
+	defaultSubscriptions := make([]dto.DefaultSubscriptionSetting, 0, len(settings.DefaultSubscriptions))
+	for _, sub := range settings.DefaultSubscriptions {
+		defaultSubscriptions = append(defaultSubscriptions, dto.DefaultSubscriptionSetting{
+			GroupID:      sub.GroupID,
+			ValidityDays: sub.ValidityDays,
+		})
+	}
 
 	response.Success(c, dto.SystemSettings{
 		RegistrationEnabled:                  settings.RegistrationEnabled,
@@ -87,6 +94,7 @@ func (h *SettingHandler) GetSettings(c *gin.Context) {
 		SoraClientEnabled:                    settings.SoraClientEnabled,
 		DefaultConcurrency:                   settings.DefaultConcurrency,
 		DefaultBalance:                       settings.DefaultBalance,
+		DefaultSubscriptions:                 defaultSubscriptions,
 		EnableModelFallback:                  settings.EnableModelFallback,
 		FallbackModelAnthropic:               settings.FallbackModelAnthropic,
 		FallbackModelOpenAI:                  settings.FallbackModelOpenAI,
@@ -146,8 +154,9 @@ type UpdateSettingsRequest struct {
 	SoraClientEnabled           bool    `json:"sora_client_enabled"`
 
 	// 默认配置
-	DefaultConcurrency int     `json:"default_concurrency"`
+	DefaultConcurrency   int                              `json:"default_concurrency"`
-	DefaultBalance     float64 `json:"default_balance"`
+	DefaultBalance       float64                          `json:"default_balance"`
+	DefaultSubscriptions []dto.DefaultSubscriptionSetting `json:"default_subscriptions"`
 
 	// Model fallback configuration
 	EnableModelFallback      bool   `json:"enable_model_fallback"`
@@ -194,6 +203,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 	if req.SMTPPort <= 0 {
 		req.SMTPPort = 587
 	}
+	req.DefaultSubscriptions = normalizeDefaultSubscriptions(req.DefaultSubscriptions)
 
 	// Turnstile 参数验证
 	if req.TurnstileEnabled {
@@ -300,6 +310,13 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		}
 		req.OpsMetricsIntervalSeconds = &v
 	}
+	defaultSubscriptions := make([]service.DefaultSubscriptionSetting, 0, len(req.DefaultSubscriptions))
+	for _, sub := range req.DefaultSubscriptions {
+		defaultSubscriptions = append(defaultSubscriptions, service.DefaultSubscriptionSetting{
+			GroupID:      sub.GroupID,
+			ValidityDays: sub.ValidityDays,
+		})
+	}
 
 	// 验证最低版本号格式（空字符串=禁用，或合法 semver）
 	if req.MinClaudeCodeVersion != "" {
@@ -343,6 +360,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		SoraClientEnabled:           req.SoraClientEnabled,
 		DefaultConcurrency:          req.DefaultConcurrency,
 		DefaultBalance:              req.DefaultBalance,
+		DefaultSubscriptions:        defaultSubscriptions,
 		EnableModelFallback:         req.EnableModelFallback,
 		FallbackModelAnthropic:      req.FallbackModelAnthropic,
 		FallbackModelOpenAI:         req.FallbackModelOpenAI,
@@ -390,6 +408,13 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		response.ErrorFrom(c, err)
 		return
 	}
+	updatedDefaultSubscriptions := make([]dto.DefaultSubscriptionSetting, 0, len(updatedSettings.DefaultSubscriptions))
+	for _, sub := range updatedSettings.DefaultSubscriptions {
+		updatedDefaultSubscriptions = append(updatedDefaultSubscriptions, dto.DefaultSubscriptionSetting{
+			GroupID:      sub.GroupID,
+			ValidityDays: sub.ValidityDays,
+		})
+	}
 
 	response.Success(c, dto.SystemSettings{
 		RegistrationEnabled:                  updatedSettings.RegistrationEnabled,
@@ -426,6 +451,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		SoraClientEnabled:                    updatedSettings.SoraClientEnabled,
 		DefaultConcurrency:                   updatedSettings.DefaultConcurrency,
 		DefaultBalance:                       updatedSettings.DefaultBalance,
+		DefaultSubscriptions:                 updatedDefaultSubscriptions,
 		EnableModelFallback:                  updatedSettings.EnableModelFallback,
 		FallbackModelAnthropic:               updatedSettings.FallbackModelAnthropic,
 		FallbackModelOpenAI:                  updatedSettings.FallbackModelOpenAI,
@@ -547,6 +573,9 @@ func diffSettings(before *service.SystemSettings, after *service.SystemSettings,
 	if before.DefaultBalance != after.DefaultBalance {
 		changed = append(changed, "default_balance")
 	}
+	if !equalDefaultSubscriptions(before.DefaultSubscriptions, after.DefaultSubscriptions) {
+		changed = append(changed, "default_subscriptions")
+	}
 	if before.EnableModelFallback != after.EnableModelFallback {
 		changed = append(changed, "enable_model_fallback")
 	}
@@ -586,6 +615,35 @@ func diffSettings(before *service.SystemSettings, after *service.SystemSettings,
 	return changed
 }
 
+func normalizeDefaultSubscriptions(input []dto.DefaultSubscriptionSetting) []dto.DefaultSubscriptionSetting {
+	if len(input) == 0 {
+		return nil
+	}
+	normalized := make([]dto.DefaultSubscriptionSetting, 0, len(input))
+	for _, item := range input {
+		if item.GroupID <= 0 || item.ValidityDays <= 0 {
+			continue
+		}
+		if item.ValidityDays > service.MaxValidityDays {
+			item.ValidityDays = service.MaxValidityDays
+		}
+		normalized = append(normalized, item)
+	}
+	return normalized
+}
+
+func equalDefaultSubscriptions(a, b []service.DefaultSubscriptionSetting) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if a[i].GroupID != b[i].GroupID || a[i].ValidityDays != b[i].ValidityDays {
+			return false
+		}
+	}
+	return true
+}
+
 // TestSMTPRequest 测试SMTP连接请求
 type TestSMTPRequest struct {
 	SMTPHost     string `json:"smtp_host" binding:"required"`

backend/internal/handler/dto/settings.go

@@ -39,8 +39,9 @@ type SystemSettings struct {
 	PurchaseSubscriptionURL     string `json:"purchase_subscription_url"`
 	SoraClientEnabled           bool   `json:"sora_client_enabled"`
 
-	DefaultConcurrency int     `json:"default_concurrency"`
+	DefaultConcurrency   int                          `json:"default_concurrency"`
-	DefaultBalance     float64 `json:"default_balance"`
+	DefaultBalance       float64                      `json:"default_balance"`
+	DefaultSubscriptions []DefaultSubscriptionSetting `json:"default_subscriptions"`
 
 	// Model fallback configuration
 	EnableModelFallback      bool   `json:"enable_model_fallback"`
@@ -62,6 +63,11 @@ type SystemSettings struct {
 	MinClaudeCodeVersion string `json:"min_claude_code_version"`
 }
 
+type DefaultSubscriptionSetting struct {
+	GroupID      int64 `json:"group_id"`
+	ValidityDays int   `json:"validity_days"`
+}
+
 type PublicSettings struct {
 	RegistrationEnabled         bool   `json:"registration_enabled"`
 	EmailVerifyEnabled          bool   `json:"email_verify_enabled"`

backend/internal/server/api_contract_test.go

@@ -499,6 +499,7 @@ func TestAPIContracts(t *testing.T) {
 					"doc_url": "https://docs.example.com",
 					"default_concurrency": 5,
 					"default_balance": 1.25,
+					"default_subscriptions": [],
 					"enable_model_fallback": false,
 					"fallback_model_anthropic": "claude-3-5-sonnet-20241022",
 					"fallback_model_antigravity": "gemini-2.5-pro",
@@ -620,7 +621,7 @@ func newContractDeps(t *testing.T) *contractDeps {
 	settingRepo := newStubSettingRepo()
 	settingService := service.NewSettingService(settingRepo, cfg)
 
-	adminService := service.NewAdminService(userRepo, groupRepo, &accountRepo, nil, proxyRepo, apiKeyRepo, redeemRepo, nil, nil, nil, nil, nil, nil)
+	adminService := service.NewAdminService(userRepo, groupRepo, &accountRepo, nil, proxyRepo, apiKeyRepo, redeemRepo, nil, nil, nil, 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/admin_auth_test.go

@@ -19,7 +19,7 @@ func TestAdminAuthJWTValidatesTokenVersion(t *testing.T) {
 	gin.SetMode(gin.TestMode)
 
 	cfg := &config.Config{JWT: config.JWTConfig{Secret: "test-secret", ExpireHour: 1}}
-	authService := service.NewAuthService(nil, nil, nil, cfg, nil, nil, nil, nil, nil)
+	authService := service.NewAuthService(nil, nil, nil, cfg, nil, nil, nil, nil, nil, nil)
 
 	admin := &service.User{
 		ID:           1,

backend/internal/server/middleware/jwt_auth_test.go

@@ -40,7 +40,7 @@ func newJWTTestEnv(users map[int64]*service.User) (*gin.Engine, *service.AuthSer
 	cfg.JWT.AccessTokenExpireMinutes = 60
 
 	userRepo := &stubJWTUserRepo{users: users}
-	authSvc := service.NewAuthService(userRepo, nil, nil, cfg, nil, nil, nil, nil, nil)
+	authSvc := service.NewAuthService(userRepo, nil, nil, cfg, nil, nil, nil, nil, nil, nil)
 	userSvc := service.NewUserService(userRepo, nil, nil)
 	mw := NewJWTAuthMiddleware(authSvc, userSvc)
 

backend/internal/service/admin_service.go

@@ -420,6 +420,8 @@ type adminServiceImpl struct {
 	proxyLatencyCache    ProxyLatencyCache
 	authCacheInvalidator APIKeyAuthCacheInvalidator
 	entClient            *dbent.Client // 用于开启数据库事务
+	settingService       *SettingService
+	defaultSubAssigner   DefaultSubscriptionAssigner
 }
 
 type userGroupRateBatchReader interface {
@@ -445,6 +447,8 @@ func NewAdminService(
 	proxyLatencyCache ProxyLatencyCache,
 	authCacheInvalidator APIKeyAuthCacheInvalidator,
 	entClient *dbent.Client,
+	settingService *SettingService,
+	defaultSubAssigner DefaultSubscriptionAssigner,
 ) AdminService {
 	return &adminServiceImpl{
 		userRepo:             userRepo,
@@ -460,6 +464,8 @@ func NewAdminService(
 		proxyLatencyCache:    proxyLatencyCache,
 		authCacheInvalidator: authCacheInvalidator,
 		entClient:            entClient,
+		settingService:       settingService,
+		defaultSubAssigner:   defaultSubAssigner,
 	}
 }
 
@@ -544,9 +550,27 @@ func (s *adminServiceImpl) CreateUser(ctx context.Context, input *CreateUserInpu
 	if err := s.userRepo.Create(ctx, user); err != nil {
 		return nil, err
 	}
+	s.assignDefaultSubscriptions(ctx, user.ID)
 	return user, nil
 }
 
+func (s *adminServiceImpl) assignDefaultSubscriptions(ctx context.Context, userID int64) {
+	if s.settingService == nil || s.defaultSubAssigner == nil || userID <= 0 {
+		return
+	}
+	items := s.settingService.GetDefaultSubscriptions(ctx)
+	for _, item := range items {
+		if _, _, err := s.defaultSubAssigner.AssignOrExtendSubscription(ctx, &AssignSubscriptionInput{
+			UserID:       userID,
+			GroupID:      item.GroupID,
+			ValidityDays: item.ValidityDays,
+			Notes:        "auto assigned by default user subscriptions setting",
+		}); err != nil {
+			logger.LegacyPrintf("service.admin", "failed to assign default subscription: user_id=%d group_id=%d err=%v", userID, item.GroupID, err)
+		}
+	}
+}
+
 func (s *adminServiceImpl) UpdateUser(ctx context.Context, id int64, input *UpdateUserInput) (*User, error) {
 	user, err := s.userRepo.GetByID(ctx, id)
 	if err != nil {

backend/internal/service/admin_service_create_user_test.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"testing"
 
+	"github.com/Wei-Shaw/sub2api/internal/config"
 	"github.com/stretchr/testify/require"
 )
 
@@ -65,3 +66,32 @@ func TestAdminService_CreateUser_CreateError(t *testing.T) {
 	require.ErrorIs(t, err, createErr)
 	require.Empty(t, repo.created)
 }
+
+func TestAdminService_CreateUser_AssignsDefaultSubscriptions(t *testing.T) {
+	repo := &userRepoStub{nextID: 21}
+	assigner := &defaultSubscriptionAssignerStub{}
+	cfg := &config.Config{
+		Default: config.DefaultConfig{
+			UserBalance:     0,
+			UserConcurrency: 1,
+		},
+	}
+	settingService := NewSettingService(&settingRepoStub{values: map[string]string{
+		SettingKeyDefaultSubscriptions: `[{"group_id":5,"validity_days":30}]`,
+	}}, cfg)
+	svc := &adminServiceImpl{
+		userRepo:           repo,
+		settingService:     settingService,
+		defaultSubAssigner: assigner,
+	}
+
+	_, err := svc.CreateUser(context.Background(), &CreateUserInput{
+		Email:    "new-user@test.com",
+		Password: "password",
+	})
+	require.NoError(t, err)
+	require.Len(t, assigner.calls, 1)
+	require.Equal(t, int64(21), assigner.calls[0].UserID)
+	require.Equal(t, int64(5), assigner.calls[0].GroupID)
+	require.Equal(t, 30, assigner.calls[0].ValidityDays)
+}

backend/internal/service/auth_service.go

@@ -56,15 +56,20 @@ type JWTClaims struct {
 
 // AuthService 认证服务
 type AuthService struct {
-	userRepo          UserRepository
+	userRepo           UserRepository
-	redeemRepo        RedeemCodeRepository
+	redeemRepo         RedeemCodeRepository
-	refreshTokenCache RefreshTokenCache
+	refreshTokenCache  RefreshTokenCache
-	cfg               *config.Config
+	cfg                *config.Config
-	settingService    *SettingService
+	settingService     *SettingService
-	emailService      *EmailService
+	emailService       *EmailService
-	turnstileService  *TurnstileService
+	turnstileService   *TurnstileService
-	emailQueueService *EmailQueueService
+	emailQueueService  *EmailQueueService
-	promoService      *PromoService
+	promoService       *PromoService
+	defaultSubAssigner DefaultSubscriptionAssigner
+}
+
+type DefaultSubscriptionAssigner interface {
+	AssignOrExtendSubscription(ctx context.Context, input *AssignSubscriptionInput) (*UserSubscription, bool, error)
 }
 
 // NewAuthService 创建认证服务实例
@@ -78,17 +83,19 @@ func NewAuthService(
 	turnstileService *TurnstileService,
 	emailQueueService *EmailQueueService,
 	promoService *PromoService,
+	defaultSubAssigner DefaultSubscriptionAssigner,
 ) *AuthService {
 	return &AuthService{
-		userRepo:          userRepo,
+		userRepo:           userRepo,
-		redeemRepo:        redeemRepo,
+		redeemRepo:         redeemRepo,
-		refreshTokenCache: refreshTokenCache,
+		refreshTokenCache:  refreshTokenCache,
-		cfg:               cfg,
+		cfg:                cfg,
-		settingService:    settingService,
+		settingService:     settingService,
-		emailService:      emailService,
+		emailService:       emailService,
-		turnstileService:  turnstileService,
+		turnstileService:   turnstileService,
-		emailQueueService: emailQueueService,
+		emailQueueService:  emailQueueService,
-		promoService:      promoService,
+		promoService:       promoService,
+		defaultSubAssigner: defaultSubAssigner,
 	}
 }
 
@@ -188,6 +195,7 @@ func (s *AuthService) RegisterWithVerification(ctx context.Context, email, passw
 		logger.LegacyPrintf("service.auth", "[Auth] Database error creating user: %v", err)
 		return "", nil, ErrServiceUnavailable
 	}
+	s.assignDefaultSubscriptions(ctx, user.ID)
 
 	// 标记邀请码为已使用（如果使用了邀请码）
 	if invitationRedeemCode != nil {
@@ -477,6 +485,7 @@ func (s *AuthService) LoginOrRegisterOAuth(ctx context.Context, email, username
 				}
 			} else {
 				user = newUser
+				s.assignDefaultSubscriptions(ctx, user.ID)
 			}
 		} else {
 			logger.LegacyPrintf("service.auth", "[Auth] Database error during oauth login: %v", err)
@@ -572,6 +581,7 @@ func (s *AuthService) LoginOrRegisterOAuthWithTokenPair(ctx context.Context, ema
 				}
 			} else {
 				user = newUser
+				s.assignDefaultSubscriptions(ctx, user.ID)
 			}
 		} else {
 			logger.LegacyPrintf("service.auth", "[Auth] Database error during oauth login: %v", err)
@@ -597,6 +607,23 @@ func (s *AuthService) LoginOrRegisterOAuthWithTokenPair(ctx context.Context, ema
 	return tokenPair, user, nil
 }
 
+func (s *AuthService) assignDefaultSubscriptions(ctx context.Context, userID int64) {
+	if s.settingService == nil || s.defaultSubAssigner == nil || userID <= 0 {
+		return
+	}
+	items := s.settingService.GetDefaultSubscriptions(ctx)
+	for _, item := range items {
+		if _, _, err := s.defaultSubAssigner.AssignOrExtendSubscription(ctx, &AssignSubscriptionInput{
+			UserID:       userID,
+			GroupID:      item.GroupID,
+			ValidityDays: item.ValidityDays,
+			Notes:        "auto assigned by default user subscriptions setting",
+		}); err != nil {
+			logger.LegacyPrintf("service.auth", "[Auth] Failed to assign default subscription: user_id=%d group_id=%d err=%v", userID, item.GroupID, err)
+		}
+	}
+}
+
 // ValidateToken 验证JWT token并返回用户声明
 func (s *AuthService) ValidateToken(tokenString string) (*JWTClaims, error) {
 	// 先做长度校验，尽早拒绝异常超长 token，降低 DoS 风险。

backend/internal/service/auth_service_register_test.go

@@ -56,6 +56,21 @@ type emailCacheStub struct {
 	err  error
 }
 
+type defaultSubscriptionAssignerStub struct {
+	calls []AssignSubscriptionInput
+	err   error
+}
+
+func (s *defaultSubscriptionAssignerStub) AssignOrExtendSubscription(_ context.Context, input *AssignSubscriptionInput) (*UserSubscription, bool, error) {
+	if input != nil {
+		s.calls = append(s.calls, *input)
+	}
+	if s.err != nil {
+		return nil, false, s.err
+	}
+	return &UserSubscription{UserID: input.UserID, GroupID: input.GroupID}, false, nil
+}
+
 func (s *emailCacheStub) GetVerificationCode(ctx context.Context, email string) (*VerificationCodeData, error) {
 	if s.err != nil {
 		return nil, s.err
@@ -123,6 +138,7 @@ func newAuthService(repo *userRepoStub, settings map[string]string, emailCache E
 		nil,
 		nil,
 		nil, // promoService
+		nil, // defaultSubAssigner
 	)
 }
 
@@ -381,3 +397,23 @@ func TestAuthService_GenerateToken_UsesMinutesWhenConfigured(t *testing.T) {
 
 	require.WithinDuration(t, claims.IssuedAt.Time.Add(90*time.Minute), claims.ExpiresAt.Time, 2*time.Second)
 }
+
+func TestAuthService_Register_AssignsDefaultSubscriptions(t *testing.T) {
+	repo := &userRepoStub{nextID: 42}
+	assigner := &defaultSubscriptionAssignerStub{}
+	service := newAuthService(repo, map[string]string{
+		SettingKeyRegistrationEnabled: "true",
+		SettingKeyDefaultSubscriptions: `[{"group_id":11,"validity_days":30},{"group_id":12,"validity_days":7}]`,
+	}, nil)
+	service.defaultSubAssigner = assigner
+
+	_, user, err := service.Register(context.Background(), "default-sub@test.com", "password")
+	require.NoError(t, err)
+	require.NotNil(t, user)
+	require.Len(t, assigner.calls, 2)
+	require.Equal(t, int64(42), assigner.calls[0].UserID)
+	require.Equal(t, int64(11), assigner.calls[0].GroupID)
+	require.Equal(t, 30, assigner.calls[0].ValidityDays)
+	require.Equal(t, int64(12), assigner.calls[1].GroupID)
+	require.Equal(t, 7, assigner.calls[1].ValidityDays)
+}

backend/internal/service/auth_service_turnstile_register_test.go

@@ -52,6 +52,7 @@ func newAuthServiceForRegisterTurnstileTest(settings map[string]string, verifier
 		turnstileService,
 		nil, // emailQueueService
 		nil, // promoService
+		nil, // defaultSubAssigner
 	)
 }
 

backend/internal/service/domain_constants.go

@@ -117,8 +117,9 @@ const (
 	SettingKeyPurchaseSubscriptionURL     = "purchase_subscription_url"     // “购买订阅”页面 URL（作为 iframe src）
 
 	// 默认配置
-	SettingKeyDefaultConcurrency = "default_concurrency" // 新用户默认并发量
+	SettingKeyDefaultConcurrency   = "default_concurrency"   // 新用户默认并发量
-	SettingKeyDefaultBalance     = "default_balance"     // 新用户默认余额
+	SettingKeyDefaultBalance       = "default_balance"       // 新用户默认余额
+	SettingKeyDefaultSubscriptions = "default_subscriptions" // 新用户默认订阅列表（JSON）
 
 	// 管理员 API Key
 	SettingKeyAdminAPIKey = "admin_api_key" // 全局管理员 API Key（用于外部系统集成）

backend/internal/service/setting_service.go

@@ -19,10 +19,18 @@ import (
 )
 
 var (
-	ErrRegistrationDisabled  = infraerrors.Forbidden("REGISTRATION_DISABLED", "registration is currently disabled")
+	ErrRegistrationDisabled   = infraerrors.Forbidden("REGISTRATION_DISABLED", "registration is currently disabled")
-	ErrSettingNotFound       = infraerrors.NotFound("SETTING_NOT_FOUND", "setting not found")
+	ErrSettingNotFound        = infraerrors.NotFound("SETTING_NOT_FOUND", "setting not found")
-	ErrSoraS3ProfileNotFound = infraerrors.NotFound("SORA_S3_PROFILE_NOT_FOUND", "sora s3 profile not found")
+	ErrSoraS3ProfileNotFound  = infraerrors.NotFound("SORA_S3_PROFILE_NOT_FOUND", "sora s3 profile not found")
-	ErrSoraS3ProfileExists   = infraerrors.Conflict("SORA_S3_PROFILE_EXISTS", "sora s3 profile already exists")
+	ErrSoraS3ProfileExists    = infraerrors.Conflict("SORA_S3_PROFILE_EXISTS", "sora s3 profile already exists")
+	ErrDefaultSubGroupInvalid = infraerrors.BadRequest(
+		"DEFAULT_SUBSCRIPTION_GROUP_INVALID",
+		"default subscription group must exist and be subscription type",
+	)
+	ErrDefaultSubGroupDuplicate = infraerrors.BadRequest(
+		"DEFAULT_SUBSCRIPTION_GROUP_DUPLICATE",
+		"default subscription group cannot be duplicated",
+	)
 )
 
 type SettingRepository interface {
@@ -56,13 +64,19 @@ const minVersionErrorTTL = 5 * time.Second
 // minVersionDBTimeout singleflight 内 DB 查询超时，独立于请求 context
 const minVersionDBTimeout = 5 * time.Second
 
+// DefaultSubscriptionGroupReader validates group references used by default subscriptions.
+type DefaultSubscriptionGroupReader interface {
+	GetByID(ctx context.Context, id int64) (*Group, error)
+}
+
 // SettingService 系统设置服务
 type SettingService struct {
-	settingRepo SettingRepository
+	settingRepo           SettingRepository
-	cfg         *config.Config
+	defaultSubGroupReader DefaultSubscriptionGroupReader
-	onUpdate    func() // Callback when settings are updated (for cache invalidation)
+	cfg                   *config.Config
-	onS3Update  func() // Callback when Sora S3 settings are updated
+	onUpdate              func() // Callback when settings are updated (for cache invalidation)
-	version     string // Application version
+	onS3Update            func() // Callback when Sora S3 settings are updated
+	version               string // Application version
 }
 
 // NewSettingService 创建系统设置服务实例
@@ -73,6 +87,11 @@ func NewSettingService(settingRepo SettingRepository, cfg *config.Config) *Setti
 	}
 }
 
+// SetDefaultSubscriptionGroupReader injects an optional group reader for default subscription validation.
+func (s *SettingService) SetDefaultSubscriptionGroupReader(reader DefaultSubscriptionGroupReader) {
+	s.defaultSubGroupReader = reader
+}
+
 // GetAllSettings 获取所有系统设置
 func (s *SettingService) GetAllSettings(ctx context.Context) (*SystemSettings, error) {
 	settings, err := s.settingRepo.GetAll(ctx)
@@ -222,6 +241,10 @@ func (s *SettingService) GetPublicSettingsForInjection(ctx context.Context) (any
 
 // UpdateSettings 更新系统设置
 func (s *SettingService) UpdateSettings(ctx context.Context, settings *SystemSettings) error {
+	if err := s.validateDefaultSubscriptionGroups(ctx, settings.DefaultSubscriptions); err != nil {
+		return err
+	}
+
 	updates := make(map[string]string)
 
 	// 注册设置
@@ -274,6 +297,11 @@ func (s *SettingService) UpdateSettings(ctx context.Context, settings *SystemSet
 	// 默认配置
 	updates[SettingKeyDefaultConcurrency] = strconv.Itoa(settings.DefaultConcurrency)
 	updates[SettingKeyDefaultBalance] = strconv.FormatFloat(settings.DefaultBalance, 'f', 8, 64)
+	defaultSubsJSON, err := json.Marshal(settings.DefaultSubscriptions)
+	if err != nil {
+		return fmt.Errorf("marshal default subscriptions: %w", err)
+	}
+	updates[SettingKeyDefaultSubscriptions] = string(defaultSubsJSON)
 
 	// Model fallback configuration
 	updates[SettingKeyEnableModelFallback] = strconv.FormatBool(settings.EnableModelFallback)
@@ -297,7 +325,7 @@ func (s *SettingService) UpdateSettings(ctx context.Context, settings *SystemSet
 	// Claude Code version check
 	updates[SettingKeyMinClaudeCodeVersion] = settings.MinClaudeCodeVersion
 
-	err := s.settingRepo.SetMultiple(ctx, updates)
+	err = s.settingRepo.SetMultiple(ctx, updates)
 	if err == nil {
 		// 先使 inflight singleflight 失效，再刷新缓存，缩小旧值覆盖新值的竞态窗口
 		minVersionSF.Forget("min_version")
@@ -312,6 +340,45 @@ func (s *SettingService) UpdateSettings(ctx context.Context, settings *SystemSet
 	return err
 }
 
+func (s *SettingService) validateDefaultSubscriptionGroups(ctx context.Context, items []DefaultSubscriptionSetting) error {
+	if len(items) == 0 {
+		return nil
+	}
+
+	checked := make(map[int64]struct{}, len(items))
+	for _, item := range items {
+		if item.GroupID <= 0 {
+			continue
+		}
+		if _, ok := checked[item.GroupID]; ok {
+			return ErrDefaultSubGroupDuplicate.WithMetadata(map[string]string{
+				"group_id": strconv.FormatInt(item.GroupID, 10),
+			})
+		}
+		checked[item.GroupID] = struct{}{}
+		if s.defaultSubGroupReader == nil {
+			continue
+		}
+
+		group, err := s.defaultSubGroupReader.GetByID(ctx, item.GroupID)
+		if err != nil {
+			if errors.Is(err, ErrGroupNotFound) {
+				return ErrDefaultSubGroupInvalid.WithMetadata(map[string]string{
+					"group_id": strconv.FormatInt(item.GroupID, 10),
+				})
+			}
+			return fmt.Errorf("get default subscription group %d: %w", item.GroupID, err)
+		}
+		if !group.IsSubscriptionType() {
+			return ErrDefaultSubGroupInvalid.WithMetadata(map[string]string{
+				"group_id": strconv.FormatInt(item.GroupID, 10),
+			})
+		}
+	}
+
+	return nil
+}
+
 // IsRegistrationEnabled 检查是否开放注册
 func (s *SettingService) IsRegistrationEnabled(ctx context.Context) bool {
 	value, err := s.settingRepo.GetValue(ctx, SettingKeyRegistrationEnabled)
@@ -411,6 +478,15 @@ func (s *SettingService) GetDefaultBalance(ctx context.Context) float64 {
 	return s.cfg.Default.UserBalance
 }
 
+// GetDefaultSubscriptions 获取新用户默认订阅配置列表。
+func (s *SettingService) GetDefaultSubscriptions(ctx context.Context) []DefaultSubscriptionSetting {
+	value, err := s.settingRepo.GetValue(ctx, SettingKeyDefaultSubscriptions)
+	if err != nil {
+		return nil
+	}
+	return parseDefaultSubscriptions(value)
+}
+
 // InitializeDefaultSettings 初始化默认设置
 func (s *SettingService) InitializeDefaultSettings(ctx context.Context) error {
 	// 检查是否已有设置
@@ -435,6 +511,7 @@ func (s *SettingService) InitializeDefaultSettings(ctx context.Context) error {
 		SettingKeySoraClientEnabled:           "false",
 		SettingKeyDefaultConcurrency:          strconv.Itoa(s.cfg.Default.UserConcurrency),
 		SettingKeyDefaultBalance:              strconv.FormatFloat(s.cfg.Default.UserBalance, 'f', 8, 64),
+		SettingKeyDefaultSubscriptions:        "[]",
 		SettingKeySMTPPort:                    "587",
 		SettingKeySMTPUseTLS:                  "false",
 		// Model fallback defaults
@@ -511,6 +588,7 @@ func (s *SettingService) parseSettings(settings map[string]string) *SystemSettin
 	} else {
 		result.DefaultBalance = s.cfg.Default.UserBalance
 	}
+	result.DefaultSubscriptions = parseDefaultSubscriptions(settings[SettingKeyDefaultSubscriptions])
 
 	// 敏感信息直接返回，方便测试连接时使用
 	result.SMTPPassword = settings[SettingKeySMTPPassword]
@@ -595,6 +673,31 @@ func isFalseSettingValue(value string) bool {
 	}
 }
 
+func parseDefaultSubscriptions(raw string) []DefaultSubscriptionSetting {
+	raw = strings.TrimSpace(raw)
+	if raw == "" {
+		return nil
+	}
+
+	var items []DefaultSubscriptionSetting
+	if err := json.Unmarshal([]byte(raw), &items); err != nil {
+		return nil
+	}
+
+	normalized := make([]DefaultSubscriptionSetting, 0, len(items))
+	for _, item := range items {
+		if item.GroupID <= 0 || item.ValidityDays <= 0 {
+			continue
+		}
+		if item.ValidityDays > MaxValidityDays {
+			item.ValidityDays = MaxValidityDays
+		}
+		normalized = append(normalized, item)
+	}
+
+	return normalized
+}
+
 // getStringOrDefault 获取字符串值或默认值
 func (s *SettingService) getStringOrDefault(settings map[string]string, key, defaultValue string) string {
 	if value, ok := settings[key]; ok && value != "" {

backend/internal/service/setting_service_update_test.go

@@ -0,0 +1,182 @@
+//go:build unit
+
+package service
+
+import (
+	"context"
+	"encoding/json"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
+	"github.com/stretchr/testify/require"
+)
+
+type settingUpdateRepoStub struct {
+	updates map[string]string
+}
+
+func (s *settingUpdateRepoStub) Get(ctx context.Context, key string) (*Setting, error) {
+	panic("unexpected Get call")
+}
+
+func (s *settingUpdateRepoStub) GetValue(ctx context.Context, key string) (string, error) {
+	panic("unexpected GetValue call")
+}
+
+func (s *settingUpdateRepoStub) Set(ctx context.Context, key, value string) error {
+	panic("unexpected Set call")
+}
+
+func (s *settingUpdateRepoStub) GetMultiple(ctx context.Context, keys []string) (map[string]string, error) {
+	panic("unexpected GetMultiple call")
+}
+
+func (s *settingUpdateRepoStub) SetMultiple(ctx context.Context, settings map[string]string) error {
+	s.updates = make(map[string]string, len(settings))
+	for k, v := range settings {
+		s.updates[k] = v
+	}
+	return nil
+}
+
+func (s *settingUpdateRepoStub) GetAll(ctx context.Context) (map[string]string, error) {
+	panic("unexpected GetAll call")
+}
+
+func (s *settingUpdateRepoStub) Delete(ctx context.Context, key string) error {
+	panic("unexpected Delete call")
+}
+
+type defaultSubGroupReaderStub struct {
+	byID  map[int64]*Group
+	errBy map[int64]error
+	calls []int64
+}
+
+func (s *defaultSubGroupReaderStub) GetByID(ctx context.Context, id int64) (*Group, error) {
+	s.calls = append(s.calls, id)
+	if err, ok := s.errBy[id]; ok {
+		return nil, err
+	}
+	if g, ok := s.byID[id]; ok {
+		return g, nil
+	}
+	return nil, ErrGroupNotFound
+}
+
+func TestSettingService_UpdateSettings_DefaultSubscriptions_ValidGroup(t *testing.T) {
+	repo := &settingUpdateRepoStub{}
+	groupReader := &defaultSubGroupReaderStub{
+		byID: map[int64]*Group{
+			11: {ID: 11, SubscriptionType: SubscriptionTypeSubscription},
+		},
+	}
+	svc := NewSettingService(repo, &config.Config{})
+	svc.SetDefaultSubscriptionGroupReader(groupReader)
+
+	err := svc.UpdateSettings(context.Background(), &SystemSettings{
+		DefaultSubscriptions: []DefaultSubscriptionSetting{
+			{GroupID: 11, ValidityDays: 30},
+		},
+	})
+	require.NoError(t, err)
+	require.Equal(t, []int64{11}, groupReader.calls)
+
+	raw, ok := repo.updates[SettingKeyDefaultSubscriptions]
+	require.True(t, ok)
+
+	var got []DefaultSubscriptionSetting
+	require.NoError(t, json.Unmarshal([]byte(raw), &got))
+	require.Equal(t, []DefaultSubscriptionSetting{
+		{GroupID: 11, ValidityDays: 30},
+	}, got)
+}
+
+func TestSettingService_UpdateSettings_DefaultSubscriptions_RejectsNonSubscriptionGroup(t *testing.T) {
+	repo := &settingUpdateRepoStub{}
+	groupReader := &defaultSubGroupReaderStub{
+		byID: map[int64]*Group{
+			12: {ID: 12, SubscriptionType: SubscriptionTypeStandard},
+		},
+	}
+	svc := NewSettingService(repo, &config.Config{})
+	svc.SetDefaultSubscriptionGroupReader(groupReader)
+
+	err := svc.UpdateSettings(context.Background(), &SystemSettings{
+		DefaultSubscriptions: []DefaultSubscriptionSetting{
+			{GroupID: 12, ValidityDays: 7},
+		},
+	})
+	require.Error(t, err)
+	require.Equal(t, "DEFAULT_SUBSCRIPTION_GROUP_INVALID", infraerrors.Reason(err))
+	require.Nil(t, repo.updates)
+}
+
+func TestSettingService_UpdateSettings_DefaultSubscriptions_RejectsNotFoundGroup(t *testing.T) {
+	repo := &settingUpdateRepoStub{}
+	groupReader := &defaultSubGroupReaderStub{
+		errBy: map[int64]error{
+			13: ErrGroupNotFound,
+		},
+	}
+	svc := NewSettingService(repo, &config.Config{})
+	svc.SetDefaultSubscriptionGroupReader(groupReader)
+
+	err := svc.UpdateSettings(context.Background(), &SystemSettings{
+		DefaultSubscriptions: []DefaultSubscriptionSetting{
+			{GroupID: 13, ValidityDays: 7},
+		},
+	})
+	require.Error(t, err)
+	require.Equal(t, "DEFAULT_SUBSCRIPTION_GROUP_INVALID", infraerrors.Reason(err))
+	require.Equal(t, "13", infraerrors.FromError(err).Metadata["group_id"])
+	require.Nil(t, repo.updates)
+}
+
+func TestSettingService_UpdateSettings_DefaultSubscriptions_RejectsDuplicateGroup(t *testing.T) {
+	repo := &settingUpdateRepoStub{}
+	groupReader := &defaultSubGroupReaderStub{
+		byID: map[int64]*Group{
+			11: {ID: 11, SubscriptionType: SubscriptionTypeSubscription},
+		},
+	}
+	svc := NewSettingService(repo, &config.Config{})
+	svc.SetDefaultSubscriptionGroupReader(groupReader)
+
+	err := svc.UpdateSettings(context.Background(), &SystemSettings{
+		DefaultSubscriptions: []DefaultSubscriptionSetting{
+			{GroupID: 11, ValidityDays: 30},
+			{GroupID: 11, ValidityDays: 60},
+		},
+	})
+	require.Error(t, err)
+	require.Equal(t, "DEFAULT_SUBSCRIPTION_GROUP_DUPLICATE", infraerrors.Reason(err))
+	require.Equal(t, "11", infraerrors.FromError(err).Metadata["group_id"])
+	require.Nil(t, repo.updates)
+}
+
+func TestSettingService_UpdateSettings_DefaultSubscriptions_RejectsDuplicateGroupWithoutGroupReader(t *testing.T) {
+	repo := &settingUpdateRepoStub{}
+	svc := NewSettingService(repo, &config.Config{})
+
+	err := svc.UpdateSettings(context.Background(), &SystemSettings{
+		DefaultSubscriptions: []DefaultSubscriptionSetting{
+			{GroupID: 11, ValidityDays: 30},
+			{GroupID: 11, ValidityDays: 60},
+		},
+	})
+	require.Error(t, err)
+	require.Equal(t, "DEFAULT_SUBSCRIPTION_GROUP_DUPLICATE", infraerrors.Reason(err))
+	require.Equal(t, "11", infraerrors.FromError(err).Metadata["group_id"])
+	require.Nil(t, repo.updates)
+}
+
+func TestParseDefaultSubscriptions_NormalizesValues(t *testing.T) {
+	got := parseDefaultSubscriptions(`[{"group_id":11,"validity_days":30},{"group_id":11,"validity_days":60},{"group_id":0,"validity_days":10},{"group_id":12,"validity_days":99999}]`)
+	require.Equal(t, []DefaultSubscriptionSetting{
+		{GroupID: 11, ValidityDays: 30},
+		{GroupID: 11, ValidityDays: 60},
+		{GroupID: 12, ValidityDays: MaxValidityDays},
+	}, got)
+}

backend/internal/service/settings_view.go

@@ -41,8 +41,9 @@ type SystemSettings struct {
 	PurchaseSubscriptionURL     string
 	SoraClientEnabled           bool
 
-	DefaultConcurrency int
+	DefaultConcurrency   int
-	DefaultBalance     float64
+	DefaultBalance       float64
+	DefaultSubscriptions []DefaultSubscriptionSetting
 
 	// Model fallback configuration
 	EnableModelFallback      bool   `json:"enable_model_fallback"`
@@ -65,6 +66,11 @@ type SystemSettings struct {
 	MinClaudeCodeVersion string
 }
 
+type DefaultSubscriptionSetting struct {
+	GroupID      int64 `json:"group_id"`
+	ValidityDays int   `json:"validity_days"`
+}
+
 type PublicSettings struct {
 	RegistrationEnabled   bool
 	EmailVerifyEnabled    bool

backend/internal/service/wire.go

@@ -284,6 +284,13 @@ func ProvideAPIKeyAuthCacheInvalidator(apiKeyService *APIKeyService) APIKeyAuthC
 	return apiKeyService
 }
 
+// ProvideSettingService wires SettingService with group reader for default subscription validation.
+func ProvideSettingService(settingRepo SettingRepository, groupRepo GroupRepository, cfg *config.Config) *SettingService {
+	svc := NewSettingService(settingRepo, cfg)
+	svc.SetDefaultSubscriptionGroupReader(groupRepo)
+	return svc
+}
+
 // ProviderSet is the Wire provider set for all services
 var ProviderSet = wire.NewSet(
 	// Core services
@@ -326,7 +333,7 @@ var ProviderSet = wire.NewSet(
 	ProvideRateLimitService,
 	NewAccountUsageService,
 	NewAccountTestService,
-	NewSettingService,
+	ProvideSettingService,
 	NewDataManagementService,
 	ProvideOpsSystemLogSink,
 	NewOpsService,
@@ -339,6 +346,7 @@ var ProviderSet = wire.NewSet(
 	ProvideEmailQueueService,
 	NewTurnstileService,
 	NewSubscriptionService,
+	wire.Bind(new(DefaultSubscriptionAssigner), new(*SubscriptionService)),
 	ProvideConcurrencyService,
 	NewUsageRecordWorkerPool,
 	ProvideSchedulerSnapshotService,

frontend/src/api/admin/settings.ts

@@ -5,6 +5,11 @@
 
 import { apiClient } from '../client'
 
+export interface DefaultSubscriptionSetting {
+  group_id: number
+  validity_days: number
+}
+
 /**
  * System settings interface
  */
@@ -20,6 +25,7 @@ export interface SystemSettings {
   // Default settings
   default_balance: number
   default_concurrency: number
+  default_subscriptions: DefaultSubscriptionSetting[]
   // OEM settings
   site_name: string
   site_logo: string
@@ -81,6 +87,7 @@ export interface UpdateSettingsRequest {
   totp_enabled?: boolean // TOTP 双因素认证
   default_balance?: number
   default_concurrency?: number
+  default_subscriptions?: DefaultSubscriptionSetting[]
   site_name?: string
   site_logo?: string
   site_subtitle?: string

frontend/src/i18n/locales/en.ts

@@ -3555,7 +3555,15 @@ export default {
         defaultBalance: 'Default Balance',
         defaultBalanceHint: 'Initial balance for new users',
         defaultConcurrency: 'Default Concurrency',
-        defaultConcurrencyHint: 'Maximum concurrent requests for new users'
+        defaultConcurrencyHint: 'Maximum concurrent requests for new users',
+        defaultSubscriptions: 'Default Subscriptions',
+        defaultSubscriptionsHint: 'Auto-assign these subscriptions when a new user is created or registered',
+        addDefaultSubscription: 'Add Default Subscription',
+        defaultSubscriptionsEmpty: 'No default subscriptions configured.',
+        defaultSubscriptionsDuplicate:
+          'Duplicate subscription group: {groupId}. Each group can only appear once.',
+        subscriptionGroup: 'Subscription Group',
+        subscriptionValidityDays: 'Validity (days)'
       },
       claudeCode: {
         title: 'Claude Code Settings',

frontend/src/i18n/locales/zh.ts

@@ -3725,7 +3725,14 @@ export default {
         defaultBalance: '默认余额',
         defaultBalanceHint: '新用户的初始余额',
         defaultConcurrency: '默认并发数',
-        defaultConcurrencyHint: '新用户的最大并发请求数'
+        defaultConcurrencyHint: '新用户的最大并发请求数',
+        defaultSubscriptions: '默认订阅列表',
+        defaultSubscriptionsHint: '新用户创建或注册时自动分配这些订阅',
+        addDefaultSubscription: '添加默认订阅',
+        defaultSubscriptionsEmpty: '未配置默认订阅。新用户不会自动获得订阅套餐。',
+        defaultSubscriptionsDuplicate: '默认订阅存在重复分组：{groupId}。每个分组只能出现一次。',
+        subscriptionGroup: '订阅分组',
+        subscriptionValidityDays: '有效期（天）'
       },
       claudeCode: {
         title: 'Claude Code 设置',

frontend/src/views/admin/SettingsView.vue

@@ -579,7 +579,7 @@
               {{ t('admin.settings.defaults.description') }}
             </p>
           </div>
-          <div class="p-6">
+          <div class="space-y-6 p-6">
             <div class="grid grid-cols-1 gap-6 md:grid-cols-2">
               <div>
                 <label class="mb-2 block text-sm font-medium text-gray-700 dark:text-gray-300">
@@ -613,6 +613,98 @@
                 </p>
               </div>
             </div>
+
+            <div class="border-t border-gray-100 pt-4 dark:border-dark-700">
+              <div class="mb-3 flex items-center justify-between">
+                <div>
+                  <label class="font-medium text-gray-900 dark:text-white">
+                    {{ t('admin.settings.defaults.defaultSubscriptions') }}
+                  </label>
+                  <p class="text-sm text-gray-500 dark:text-gray-400">
+                    {{ t('admin.settings.defaults.defaultSubscriptionsHint') }}
+                  </p>
+                </div>
+                <button
+                  type="button"
+                  class="btn btn-secondary btn-sm"
+                  @click="addDefaultSubscription"
+                  :disabled="subscriptionGroups.length === 0"
+                >
+                  {{ t('admin.settings.defaults.addDefaultSubscription') }}
+                </button>
+              </div>
+
+              <div
+                v-if="form.default_subscriptions.length === 0"
+                class="rounded border border-dashed border-gray-300 px-4 py-3 text-sm text-gray-500 dark:border-dark-600 dark:text-gray-400"
+              >
+                {{ t('admin.settings.defaults.defaultSubscriptionsEmpty') }}
+              </div>
+
+              <div v-else class="space-y-3">
+                <div
+                  v-for="(item, index) in form.default_subscriptions"
+                  :key="`default-sub-${index}`"
+                  class="grid grid-cols-1 gap-3 rounded border border-gray-200 p-3 md:grid-cols-[1fr_160px_auto] dark:border-dark-600"
+                >
+                  <div>
+                    <label class="mb-1 block text-xs font-medium text-gray-600 dark:text-gray-400">
+                      {{ t('admin.settings.defaults.subscriptionGroup') }}
+                    </label>
+                    <Select
+                      v-model="item.group_id"
+                      class="default-sub-group-select"
+                      :options="defaultSubscriptionGroupOptions"
+                      :placeholder="t('admin.settings.defaults.subscriptionGroup')"
+                    >
+                      <template #selected="{ option }">
+                        <GroupBadge
+                          v-if="option"
+                          :name="(option as unknown as DefaultSubscriptionGroupOption).label"
+                          :platform="(option as unknown as DefaultSubscriptionGroupOption).platform"
+                          :subscription-type="(option as unknown as DefaultSubscriptionGroupOption).subscriptionType"
+                          :rate-multiplier="(option as unknown as DefaultSubscriptionGroupOption).rate"
+                        />
+                        <span v-else class="text-gray-400">
+                          {{ t('admin.settings.defaults.subscriptionGroup') }}
+                        </span>
+                      </template>
+                      <template #option="{ option, selected }">
+                        <GroupOptionItem
+                          :name="(option as unknown as DefaultSubscriptionGroupOption).label"
+                          :platform="(option as unknown as DefaultSubscriptionGroupOption).platform"
+                          :subscription-type="(option as unknown as DefaultSubscriptionGroupOption).subscriptionType"
+                          :rate-multiplier="(option as unknown as DefaultSubscriptionGroupOption).rate"
+                          :description="(option as unknown as DefaultSubscriptionGroupOption).description"
+                          :selected="selected"
+                        />
+                      </template>
+                    </Select>
+                  </div>
+                  <div>
+                    <label class="mb-1 block text-xs font-medium text-gray-600 dark:text-gray-400">
+                      {{ t('admin.settings.defaults.subscriptionValidityDays') }}
+                    </label>
+                    <input
+                      v-model.number="item.validity_days"
+                      type="number"
+                      min="1"
+                      max="36500"
+                      class="input h-[42px]"
+                    />
+                  </div>
+                  <div class="flex items-end">
+                    <button
+                      type="button"
+                      class="btn btn-secondary default-sub-delete-btn w-full text-red-600 hover:text-red-700 dark:text-red-400"
+                      @click="removeDefaultSubscription(index)"
+                    >
+                      {{ t('common.delete') }}
+                    </button>
+                  </div>
+                </div>
+              </div>
+            </div>
           </div>
         </div>
 
@@ -1157,9 +1249,17 @@
 import { ref, reactive, computed, onMounted } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { adminAPI } from '@/api'
-import type { SystemSettings, UpdateSettingsRequest } from '@/api/admin/settings'
+import type {
+  SystemSettings,
+  UpdateSettingsRequest,
+  DefaultSubscriptionSetting
+} from '@/api/admin/settings'
+import type { AdminGroup } from '@/types'
 import AppLayout from '@/components/layout/AppLayout.vue'
 import Icon from '@/components/icons/Icon.vue'
+import Select from '@/components/common/Select.vue'
+import GroupBadge from '@/components/common/GroupBadge.vue'
+import GroupOptionItem from '@/components/common/GroupOptionItem.vue'
 import Toggle from '@/components/common/Toggle.vue'
 import { useClipboard } from '@/composables/useClipboard'
 import { useAppStore } from '@/stores'
@@ -1181,6 +1281,7 @@ const adminApiKeyExists = ref(false)
 const adminApiKeyMasked = ref('')
 const adminApiKeyOperating = ref(false)
 const newAdminApiKey = ref('')
+const subscriptionGroups = ref<AdminGroup[]>([])
 
 // Stream Timeout 状态
 const streamTimeoutLoading = ref(true)
@@ -1193,6 +1294,16 @@ const streamTimeoutForm = reactive({
   threshold_window_minutes: 10
 })
 
+interface DefaultSubscriptionGroupOption {
+  value: number
+  label: string
+  description: string | null
+  platform: AdminGroup['platform']
+  subscriptionType: AdminGroup['subscription_type']
+  rate: number
+  [key: string]: unknown
+}
+
 type SettingsForm = SystemSettings & {
   smtp_password: string
   turnstile_secret_key: string
@@ -1209,6 +1320,7 @@ const form = reactive<SettingsForm>({
   totp_encryption_key_configured: false,
   default_balance: 0,
   default_concurrency: 1,
+  default_subscriptions: [],
   site_name: 'Sub2API',
   site_logo: '',
   site_subtitle: 'Subscription to API Conversion Platform',
@@ -1257,6 +1369,17 @@ const form = reactive<SettingsForm>({
   min_claude_code_version: ''
 })
 
+const defaultSubscriptionGroupOptions = computed<DefaultSubscriptionGroupOption[]>(() =>
+  subscriptionGroups.value.map((group) => ({
+    value: group.id,
+    label: group.name,
+    description: group.description,
+    platform: group.platform,
+    subscriptionType: group.subscription_type,
+    rate: group.rate_multiplier
+  }))
+)
+
 // LinuxDo OAuth redirect URL suggestion
 const linuxdoRedirectUrlSuggestion = computed(() => {
   if (typeof window === 'undefined') return ''
@@ -1316,6 +1439,14 @@ async function loadSettings() {
   try {
     const settings = await adminAPI.settings.getSettings()
     Object.assign(form, settings)
+    form.default_subscriptions = Array.isArray(settings.default_subscriptions)
+      ? settings.default_subscriptions
+          .filter((item) => item.group_id > 0 && item.validity_days > 0)
+          .map((item) => ({
+            group_id: item.group_id,
+            validity_days: item.validity_days
+          }))
+      : []
     form.smtp_password = ''
     form.turnstile_secret_key = ''
     form.linuxdo_connect_client_secret = ''
@@ -1328,9 +1459,60 @@ async function loadSettings() {
   }
 }
 
+async function loadSubscriptionGroups() {
+  try {
+    const groups = await adminAPI.groups.getAll()
+    subscriptionGroups.value = groups.filter(
+      (group) => group.subscription_type === 'subscription' && group.status === 'active'
+    )
+  } catch (error) {
+    console.error('Failed to load subscription groups:', error)
+    subscriptionGroups.value = []
+  }
+}
+
+function addDefaultSubscription() {
+  if (subscriptionGroups.value.length === 0) return
+  const existing = new Set(form.default_subscriptions.map((item) => item.group_id))
+  const candidate = subscriptionGroups.value.find((group) => !existing.has(group.id))
+  if (!candidate) return
+  form.default_subscriptions.push({
+    group_id: candidate.id,
+    validity_days: 30
+  })
+}
+
+function removeDefaultSubscription(index: number) {
+  form.default_subscriptions.splice(index, 1)
+}
+
 async function saveSettings() {
   saving.value = true
   try {
+    const normalizedDefaultSubscriptions = form.default_subscriptions
+      .filter((item) => item.group_id > 0 && item.validity_days > 0)
+      .map((item: DefaultSubscriptionSetting) => ({
+        group_id: item.group_id,
+        validity_days: Math.min(36500, Math.max(1, Math.floor(item.validity_days)))
+      }))
+
+    const seenGroupIDs = new Set<number>()
+    const duplicateDefaultSubscription = normalizedDefaultSubscriptions.find((item) => {
+      if (seenGroupIDs.has(item.group_id)) {
+        return true
+      }
+      seenGroupIDs.add(item.group_id)
+      return false
+    })
+    if (duplicateDefaultSubscription) {
+      appStore.showError(
+        t('admin.settings.defaults.defaultSubscriptionsDuplicate', {
+          groupId: duplicateDefaultSubscription.group_id
+        })
+      )
+      return
+    }
+
     const payload: UpdateSettingsRequest = {
       registration_enabled: form.registration_enabled,
       email_verify_enabled: form.email_verify_enabled,
@@ -1340,6 +1522,7 @@ async function saveSettings() {
       totp_enabled: form.totp_enabled,
       default_balance: form.default_balance,
       default_concurrency: form.default_concurrency,
+      default_subscriptions: normalizedDefaultSubscriptions,
       site_name: form.site_name,
       site_logo: form.site_logo,
       site_subtitle: form.site_subtitle,
@@ -1538,7 +1721,18 @@ async function saveStreamTimeoutSettings() {
 
 onMounted(() => {
   loadSettings()
+  loadSubscriptionGroups()
   loadAdminApiKey()
   loadStreamTimeoutSettings()
 })
 </script>
+
+<style scoped>
+.default-sub-group-select :deep(.select-trigger) {
+  @apply h-[42px];
+}
+
+.default-sub-delete-btn {
+  @apply h-[42px];
+}
+</style>