feat: enhance proxy management

backend/internal/handler/admin/proxy_handler.go

@@ -196,6 +196,28 @@ func (h *ProxyHandler) Delete(c *gin.Context) {
 	response.Success(c, gin.H{"message": "Proxy deleted successfully"})
 }
 
+// BatchDelete handles batch deleting proxies
+// POST /api/v1/admin/proxies/batch-delete
+func (h *ProxyHandler) BatchDelete(c *gin.Context) {
+	type BatchDeleteRequest struct {
+		IDs []int64 `json:"ids" binding:"required,min=1"`
+	}
+
+	var req BatchDeleteRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+
+	result, err := h.adminService.BatchDeleteProxies(c.Request.Context(), req.IDs)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	response.Success(c, result)
+}
+
 // Test handles testing proxy connectivity
 // POST /api/v1/admin/proxies/:id/test
 func (h *ProxyHandler) Test(c *gin.Context) {
@@ -243,19 +265,17 @@ func (h *ProxyHandler) GetProxyAccounts(c *gin.Context) {
 		return
 	}
 
-	page, pageSize := response.ParsePagination(c)
-
-	accounts, total, err := h.adminService.GetProxyAccounts(c.Request.Context(), proxyID, page, pageSize)
+	accounts, err := h.adminService.GetProxyAccounts(c.Request.Context(), proxyID)
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
 	}
 
-	out := make([]dto.Account, 0, len(accounts))
+	out := make([]dto.ProxyAccountSummary, 0, len(accounts))
 	for i := range accounts {
-		out = append(out, *dto.AccountFromService(&accounts[i]))
+		out = append(out, *dto.ProxyAccountSummaryFromService(&accounts[i]))
 	}
-	response.Paginated(c, out, total, page, pageSize)
+	response.Success(c, out)
 }
 
 // BatchCreateProxyItem represents a single proxy in batch create request

backend/internal/handler/dto/mappers.go

@@ -212,8 +212,24 @@ func ProxyWithAccountCountFromService(p *service.ProxyWithAccountCount) *ProxyWi
 		return nil
 	}
 	return &ProxyWithAccountCount{
-		Proxy:        *ProxyFromService(&p.Proxy),
-		AccountCount: p.AccountCount,
+		Proxy:          *ProxyFromService(&p.Proxy),
+		AccountCount:   p.AccountCount,
+		LatencyMs:      p.LatencyMs,
+		LatencyStatus:  p.LatencyStatus,
+		LatencyMessage: p.LatencyMessage,
+	}
+}
+
+func ProxyAccountSummaryFromService(a *service.ProxyAccountSummary) *ProxyAccountSummary {
+	if a == nil {
+		return nil
+	}
+	return &ProxyAccountSummary{
+		ID:       a.ID,
+		Name:     a.Name,
+		Platform: a.Platform,
+		Type:     a.Type,
+		Notes:    a.Notes,
 	}
 }
 

backend/internal/handler/dto/types.go

@@ -129,7 +129,18 @@ type Proxy struct {
 
 type ProxyWithAccountCount struct {
 	Proxy
-	AccountCount int64 `json:"account_count"`
+	AccountCount   int64  `json:"account_count"`
+	LatencyMs      *int64 `json:"latency_ms,omitempty"`
+	LatencyStatus  string `json:"latency_status,omitempty"`
+	LatencyMessage string `json:"latency_message,omitempty"`
+}
+
+type ProxyAccountSummary struct {
+	ID       int64   `json:"id"`
+	Name     string  `json:"name"`
+	Platform string  `json:"platform"`
+	Type     string  `json:"type"`
+	Notes    *string `json:"notes,omitempty"`
 }
 
 type RedeemCode struct {

backend/internal/repository/proxy_latency_cache.go

@@ -0,0 +1,74 @@
+package repository
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/redis/go-redis/v9"
+)
+
+const proxyLatencyKeyPrefix = "proxy:latency:"
+
+func proxyLatencyKey(proxyID int64) string {
+	return fmt.Sprintf("%s%d", proxyLatencyKeyPrefix, proxyID)
+}
+
+type proxyLatencyCache struct {
+	rdb *redis.Client
+}
+
+func NewProxyLatencyCache(rdb *redis.Client) service.ProxyLatencyCache {
+	return &proxyLatencyCache{rdb: rdb}
+}
+
+func (c *proxyLatencyCache) GetProxyLatencies(ctx context.Context, proxyIDs []int64) (map[int64]*service.ProxyLatencyInfo, error) {
+	results := make(map[int64]*service.ProxyLatencyInfo)
+	if len(proxyIDs) == 0 {
+		return results, nil
+	}
+
+	keys := make([]string, 0, len(proxyIDs))
+	for _, id := range proxyIDs {
+		keys = append(keys, proxyLatencyKey(id))
+	}
+
+	values, err := c.rdb.MGet(ctx, keys...).Result()
+	if err != nil {
+		return results, err
+	}
+
+	for i, raw := range values {
+		if raw == nil {
+			continue
+		}
+		var payload []byte
+		switch v := raw.(type) {
+		case string:
+			payload = []byte(v)
+		case []byte:
+			payload = v
+		default:
+			continue
+		}
+		var info service.ProxyLatencyInfo
+		if err := json.Unmarshal(payload, &info); err != nil {
+			continue
+		}
+		results[proxyIDs[i]] = &info
+	}
+
+	return results, nil
+}
+
+func (c *proxyLatencyCache) SetProxyLatency(ctx context.Context, proxyID int64, info *service.ProxyLatencyInfo) error {
+	if info == nil {
+		return nil
+	}
+	payload, err := json.Marshal(info)
+	if err != nil {
+		return err
+	}
+	return c.rdb.Set(ctx, proxyLatencyKey(proxyID), payload, 0).Err()
+}

backend/internal/repository/proxy_probe_service.go

@@ -34,7 +34,10 @@ func NewProxyExitInfoProber(cfg *config.Config) service.ProxyExitInfoProber {
 	}
 }
 
-const defaultIPInfoURL = "https://ipinfo.io/json"
+const (
+	defaultIPInfoURL         = "https://ipinfo.io/json"
+	defaultProxyProbeTimeout = 30 * time.Second
+)
 
 type proxyProbeService struct {
 	ipInfoURL          string
@@ -46,7 +49,7 @@ type proxyProbeService struct {
 func (s *proxyProbeService) ProbeProxy(ctx context.Context, proxyURL string) (*service.ProxyExitInfo, int64, error) {
 	client, err := httpclient.GetClient(httpclient.Options{
 		ProxyURL:           proxyURL,
-		Timeout:            15 * time.Second,
+		Timeout:            defaultProxyProbeTimeout,
 		InsecureSkipVerify: s.insecureSkipVerify,
 		ProxyStrict:        true,
 		ValidateResolvedIP: s.validateResolvedIP,

backend/internal/repository/proxy_repo.go

@@ -219,12 +219,54 @@ func (r *proxyRepository) ExistsByHostPortAuth(ctx context.Context, host string,
 // CountAccountsByProxyID returns the number of accounts using a specific proxy
 func (r *proxyRepository) CountAccountsByProxyID(ctx context.Context, proxyID int64) (int64, error) {
 	var count int64
-	if err := scanSingleRow(ctx, r.sql, "SELECT COUNT(*) FROM accounts WHERE proxy_id = $1", []any{proxyID}, &count); err != nil {
+	if err := scanSingleRow(ctx, r.sql, "SELECT COUNT(*) FROM accounts WHERE proxy_id = $1 AND deleted_at IS NULL", []any{proxyID}, &count); err != nil {
 		return 0, err
 	}
 	return count, nil
 }
 
+func (r *proxyRepository) ListAccountSummariesByProxyID(ctx context.Context, proxyID int64) ([]service.ProxyAccountSummary, error) {
+	rows, err := r.sql.QueryContext(ctx, `
+		SELECT id, name, platform, type, notes
+		FROM accounts
+		WHERE proxy_id = $1 AND deleted_at IS NULL
+		ORDER BY id DESC
+	`, proxyID)
+	if err != nil {
+		return nil, err
+	}
+	defer func() { _ = rows.Close() }()
+
+	out := make([]service.ProxyAccountSummary, 0)
+	for rows.Next() {
+		var (
+			id       int64
+			name     string
+			platform string
+			accType  string
+			notes    sql.NullString
+		)
+		if err := rows.Scan(&id, &name, &platform, &accType, &notes); err != nil {
+			return nil, err
+		}
+		var notesPtr *string
+		if notes.Valid {
+			notesPtr = &notes.String
+		}
+		out = append(out, service.ProxyAccountSummary{
+			ID:       id,
+			Name:     name,
+			Platform: platform,
+			Type:     accType,
+			Notes:    notesPtr,
+		})
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // GetAccountCountsForProxies returns a map of proxy ID to account count for all proxies
 func (r *proxyRepository) GetAccountCountsForProxies(ctx context.Context) (counts map[int64]int64, err error) {
 	rows, err := r.sql.QueryContext(ctx, "SELECT proxy_id, COUNT(*) AS count FROM accounts WHERE proxy_id IS NOT NULL AND deleted_at IS NULL GROUP BY proxy_id")

backend/internal/repository/wire.go

@@ -69,6 +69,7 @@ var ProviderSet = wire.NewSet(
 	NewGeminiTokenCache,
 	NewSchedulerCache,
 	NewSchedulerOutboxRepository,
+	NewProxyLatencyCache,
 
 	// HTTP service ports (DI Strategy A: return interface directly)
 	NewTurnstileVerifier,

backend/internal/server/api_contract_test.go

@@ -262,11 +262,11 @@ func TestAPIContracts(t *testing.T) {
 			name: "GET /api/v1/admin/settings",
 			setup: func(t *testing.T, deps *contractDeps) {
 				t.Helper()
-					deps.settingRepo.SetAll(map[string]string{
-						service.SettingKeyRegistrationEnabled: "true",
-						service.SettingKeyEmailVerifyEnabled:  "false",
+				deps.settingRepo.SetAll(map[string]string{
+					service.SettingKeyRegistrationEnabled: "true",
+					service.SettingKeyEmailVerifyEnabled:  "false",
 
-						service.SettingKeySMTPHost:     "smtp.example.com",
+					service.SettingKeySMTPHost:     "smtp.example.com",
 					service.SettingKeySMTPPort:     "587",
 					service.SettingKeySMTPUsername: "user",
 					service.SettingKeySMTPPassword: "secret",
@@ -285,15 +285,15 @@ func TestAPIContracts(t *testing.T) {
 					service.SettingKeyContactInfo:  "support",
 					service.SettingKeyDocURL:       "https://docs.example.com",
 
-						service.SettingKeyDefaultConcurrency: "5",
-						service.SettingKeyDefaultBalance:     "1.25",
+					service.SettingKeyDefaultConcurrency: "5",
+					service.SettingKeyDefaultBalance:     "1.25",
 
-						service.SettingKeyOpsMonitoringEnabled:         "false",
-						service.SettingKeyOpsRealtimeMonitoringEnabled: "true",
-						service.SettingKeyOpsQueryModeDefault:          "auto",
-						service.SettingKeyOpsMetricsIntervalSeconds:    "60",
-					})
-				},
+					service.SettingKeyOpsMonitoringEnabled:         "false",
+					service.SettingKeyOpsRealtimeMonitoringEnabled: "true",
+					service.SettingKeyOpsQueryModeDefault:          "auto",
+					service.SettingKeyOpsMetricsIntervalSeconds:    "60",
+				})
+			},
 			method:     http.MethodGet,
 			path:       "/api/v1/admin/settings",
 			wantStatus: http.StatusOK,
@@ -435,7 +435,7 @@ 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)
+	adminService := service.NewAdminService(userRepo, groupRepo, &accountRepo, proxyRepo, apiKeyRepo, redeemRepo, nil, nil, nil, nil)
 	authHandler := handler.NewAuthHandler(cfg, nil, userService, settingService, nil)
 	apiKeyHandler := handler.NewAPIKeyHandler(apiKeyService)
 	usageHandler := handler.NewUsageHandler(usageService, apiKeyService)

backend/internal/server/routes/admin.go

@@ -250,6 +250,7 @@ func registerProxyRoutes(admin *gin.RouterGroup, h *handler.Handlers) {
 		proxies.POST("/:id/test", h.Admin.Proxy.Test)
 		proxies.GET("/:id/stats", h.Admin.Proxy.GetStats)
 		proxies.GET("/:id/accounts", h.Admin.Proxy.GetProxyAccounts)
+		proxies.POST("/batch-delete", h.Admin.Proxy.BatchDelete)
 		proxies.POST("/batch", h.Admin.Proxy.BatchCreate)
 	}
 }

backend/internal/service/admin_service.go

@@ -54,7 +54,8 @@ type AdminService interface {
 	CreateProxy(ctx context.Context, input *CreateProxyInput) (*Proxy, error)
 	UpdateProxy(ctx context.Context, id int64, input *UpdateProxyInput) (*Proxy, error)
 	DeleteProxy(ctx context.Context, id int64) error
-	GetProxyAccounts(ctx context.Context, proxyID int64, page, pageSize int) ([]Account, int64, error)
+	BatchDeleteProxies(ctx context.Context, ids []int64) (*ProxyBatchDeleteResult, error)
+	GetProxyAccounts(ctx context.Context, proxyID int64) ([]ProxyAccountSummary, error)
 	CheckProxyExists(ctx context.Context, host string, port int, username, password string) (bool, error)
 	TestProxy(ctx context.Context, id int64) (*ProxyTestResult, error)
 
@@ -220,6 +221,16 @@ type GenerateRedeemCodesInput struct {
 	ValidityDays int    // 订阅类型专用：有效天数
 }
 
+type ProxyBatchDeleteResult struct {
+	DeletedIDs []int64                   `json:"deleted_ids"`
+	Skipped    []ProxyBatchDeleteSkipped `json:"skipped"`
+}
+
+type ProxyBatchDeleteSkipped struct {
+	ID     int64  `json:"id"`
+	Reason string `json:"reason"`
+}
+
 // ProxyTestResult represents the result of testing a proxy
 type ProxyTestResult struct {
 	Success   bool   `json:"success"`
@@ -254,6 +265,7 @@ type adminServiceImpl struct {
 	redeemCodeRepo       RedeemCodeRepository
 	billingCacheService  *BillingCacheService
 	proxyProber          ProxyExitInfoProber
+	proxyLatencyCache    ProxyLatencyCache
 	authCacheInvalidator APIKeyAuthCacheInvalidator
 }
 
@@ -267,6 +279,7 @@ func NewAdminService(
 	redeemCodeRepo RedeemCodeRepository,
 	billingCacheService *BillingCacheService,
 	proxyProber ProxyExitInfoProber,
+	proxyLatencyCache ProxyLatencyCache,
 	authCacheInvalidator APIKeyAuthCacheInvalidator,
 ) AdminService {
 	return &adminServiceImpl{
@@ -278,6 +291,7 @@ func NewAdminService(
 		redeemCodeRepo:       redeemCodeRepo,
 		billingCacheService:  billingCacheService,
 		proxyProber:          proxyProber,
+		proxyLatencyCache:    proxyLatencyCache,
 		authCacheInvalidator: authCacheInvalidator,
 	}
 }
@@ -1069,6 +1083,7 @@ func (s *adminServiceImpl) ListProxiesWithAccountCount(ctx context.Context, page
 	if err != nil {
 		return nil, 0, err
 	}
+	s.attachProxyLatency(ctx, proxies)
 	return proxies, result.Total, nil
 }
 
@@ -1077,7 +1092,12 @@ func (s *adminServiceImpl) GetAllProxies(ctx context.Context) ([]Proxy, error) {
 }
 
 func (s *adminServiceImpl) GetAllProxiesWithAccountCount(ctx context.Context) ([]ProxyWithAccountCount, error) {
-	return s.proxyRepo.ListActiveWithAccountCount(ctx)
+	proxies, err := s.proxyRepo.ListActiveWithAccountCount(ctx)
+	if err != nil {
+		return nil, err
+	}
+	s.attachProxyLatency(ctx, proxies)
+	return proxies, nil
 }
 
 func (s *adminServiceImpl) GetProxy(ctx context.Context, id int64) (*Proxy, error) {
@@ -1097,6 +1117,8 @@ func (s *adminServiceImpl) CreateProxy(ctx context.Context, input *CreateProxyIn
 	if err := s.proxyRepo.Create(ctx, proxy); err != nil {
 		return nil, err
 	}
+	// Probe latency asynchronously so creation isn't blocked by network timeout.
+	go s.probeProxyLatency(context.Background(), proxy)
 	return proxy, nil
 }
 
@@ -1135,12 +1157,53 @@ func (s *adminServiceImpl) UpdateProxy(ctx context.Context, id int64, input *Upd
 }
 
 func (s *adminServiceImpl) DeleteProxy(ctx context.Context, id int64) error {
+	count, err := s.proxyRepo.CountAccountsByProxyID(ctx, id)
+	if err != nil {
+		return err
+	}
+	if count > 0 {
+		return ErrProxyInUse
+	}
 	return s.proxyRepo.Delete(ctx, id)
 }
 
-func (s *adminServiceImpl) GetProxyAccounts(ctx context.Context, proxyID int64, page, pageSize int) ([]Account, int64, error) {
-	// Return mock data for now - would need a dedicated repository method
-	return []Account{}, 0, nil
+func (s *adminServiceImpl) BatchDeleteProxies(ctx context.Context, ids []int64) (*ProxyBatchDeleteResult, error) {
+	result := &ProxyBatchDeleteResult{}
+	if len(ids) == 0 {
+		return result, nil
+	}
+
+	for _, id := range ids {
+		count, err := s.proxyRepo.CountAccountsByProxyID(ctx, id)
+		if err != nil {
+			result.Skipped = append(result.Skipped, ProxyBatchDeleteSkipped{
+				ID:     id,
+				Reason: err.Error(),
+			})
+			continue
+		}
+		if count > 0 {
+			result.Skipped = append(result.Skipped, ProxyBatchDeleteSkipped{
+				ID:     id,
+				Reason: ErrProxyInUse.Error(),
+			})
+			continue
+		}
+		if err := s.proxyRepo.Delete(ctx, id); err != nil {
+			result.Skipped = append(result.Skipped, ProxyBatchDeleteSkipped{
+				ID:     id,
+				Reason: err.Error(),
+			})
+			continue
+		}
+		result.DeletedIDs = append(result.DeletedIDs, id)
+	}
+
+	return result, nil
+}
+
+func (s *adminServiceImpl) GetProxyAccounts(ctx context.Context, proxyID int64) ([]ProxyAccountSummary, error) {
+	return s.proxyRepo.ListAccountSummariesByProxyID(ctx, proxyID)
 }
 
 func (s *adminServiceImpl) CheckProxyExists(ctx context.Context, host string, port int, username, password string) (bool, error) {
@@ -1240,12 +1303,24 @@ func (s *adminServiceImpl) TestProxy(ctx context.Context, id int64) (*ProxyTestR
 	proxyURL := proxy.URL()
 	exitInfo, latencyMs, err := s.proxyProber.ProbeProxy(ctx, proxyURL)
 	if err != nil {
+		s.saveProxyLatency(ctx, id, &ProxyLatencyInfo{
+			Success:   false,
+			Message:   err.Error(),
+			UpdatedAt: time.Now(),
+		})
 		return &ProxyTestResult{
 			Success: false,
 			Message: err.Error(),
 		}, nil
 	}
 
+	latency := latencyMs
+	s.saveProxyLatency(ctx, id, &ProxyLatencyInfo{
+		Success:   true,
+		LatencyMs: &latency,
+		Message:   "Proxy is accessible",
+		UpdatedAt: time.Now(),
+	})
 	return &ProxyTestResult{
 		Success:   true,
 		Message:   "Proxy is accessible",
@@ -1257,6 +1332,29 @@ func (s *adminServiceImpl) TestProxy(ctx context.Context, id int64) (*ProxyTestR
 	}, nil
 }
 
+func (s *adminServiceImpl) probeProxyLatency(ctx context.Context, proxy *Proxy) {
+	if s.proxyProber == nil || proxy == nil {
+		return
+	}
+	_, latencyMs, err := s.proxyProber.ProbeProxy(ctx, proxy.URL())
+	if err != nil {
+		s.saveProxyLatency(ctx, proxy.ID, &ProxyLatencyInfo{
+			Success:   false,
+			Message:   err.Error(),
+			UpdatedAt: time.Now(),
+		})
+		return
+	}
+
+	latency := latencyMs
+	s.saveProxyLatency(ctx, proxy.ID, &ProxyLatencyInfo{
+		Success:   true,
+		LatencyMs: &latency,
+		Message:   "Proxy is accessible",
+		UpdatedAt: time.Now(),
+	})
+}
+
 // checkMixedChannelRisk 检查分组中是否存在混合渠道（Antigravity + Anthropic）
 // 如果存在混合，返回错误提示用户确认
 func (s *adminServiceImpl) checkMixedChannelRisk(ctx context.Context, currentAccountID int64, currentAccountPlatform string, groupIDs []int64) error {
@@ -1306,6 +1404,46 @@ func (s *adminServiceImpl) checkMixedChannelRisk(ctx context.Context, currentAcc
 	return nil
 }
 
+func (s *adminServiceImpl) attachProxyLatency(ctx context.Context, proxies []ProxyWithAccountCount) {
+	if s.proxyLatencyCache == nil || len(proxies) == 0 {
+		return
+	}
+
+	ids := make([]int64, 0, len(proxies))
+	for i := range proxies {
+		ids = append(ids, proxies[i].ID)
+	}
+
+	latencies, err := s.proxyLatencyCache.GetProxyLatencies(ctx, ids)
+	if err != nil {
+		log.Printf("Warning: load proxy latency cache failed: %v", err)
+		return
+	}
+
+	for i := range proxies {
+		info := latencies[proxies[i].ID]
+		if info == nil {
+			continue
+		}
+		if info.Success {
+			proxies[i].LatencyStatus = "success"
+			proxies[i].LatencyMs = info.LatencyMs
+		} else {
+			proxies[i].LatencyStatus = "failed"
+		}
+		proxies[i].LatencyMessage = info.Message
+	}
+}
+
+func (s *adminServiceImpl) saveProxyLatency(ctx context.Context, proxyID int64, info *ProxyLatencyInfo) {
+	if s.proxyLatencyCache == nil || info == nil {
+		return
+	}
+	if err := s.proxyLatencyCache.SetProxyLatency(ctx, proxyID, info); err != nil {
+		log.Printf("Warning: store proxy latency cache failed: %v", err)
+	}
+}
+
 // getAccountPlatform 根据账号 platform 判断混合渠道检查用的平台标识
 func getAccountPlatform(accountPlatform string) string {
 	switch strings.ToLower(strings.TrimSpace(accountPlatform)) {

backend/internal/service/admin_service_delete_test.go

@@ -153,8 +153,10 @@ func (s *groupRepoStub) DeleteAccountGroupsByGroupID(ctx context.Context, groupI
 }
 
 type proxyRepoStub struct {
-	deleteErr  error
-	deletedIDs []int64
+	deleteErr    error
+	countErr     error
+	accountCount int64
+	deletedIDs   []int64
 }
 
 func (s *proxyRepoStub) Create(ctx context.Context, proxy *Proxy) error {
@@ -199,7 +201,14 @@ func (s *proxyRepoStub) ExistsByHostPortAuth(ctx context.Context, host string, p
 }
 
 func (s *proxyRepoStub) CountAccountsByProxyID(ctx context.Context, proxyID int64) (int64, error) {
-	panic("unexpected CountAccountsByProxyID call")
+	if s.countErr != nil {
+		return 0, s.countErr
+	}
+	return s.accountCount, nil
+}
+
+func (s *proxyRepoStub) ListAccountSummariesByProxyID(ctx context.Context, proxyID int64) ([]ProxyAccountSummary, error) {
+	panic("unexpected ListAccountSummariesByProxyID call")
 }
 
 type redeemRepoStub struct {
@@ -409,6 +418,15 @@ func TestAdminService_DeleteProxy_Idempotent(t *testing.T) {
 	require.Equal(t, []int64{404}, repo.deletedIDs)
 }
 
+func TestAdminService_DeleteProxy_InUse(t *testing.T) {
+	repo := &proxyRepoStub{accountCount: 2}
+	svc := &adminServiceImpl{proxyRepo: repo}
+
+	err := svc.DeleteProxy(context.Background(), 77)
+	require.ErrorIs(t, err, ErrProxyInUse)
+	require.Empty(t, repo.deletedIDs)
+}
+
 func TestAdminService_DeleteProxy_Error(t *testing.T) {
 	deleteErr := errors.New("delete failed")
 	repo := &proxyRepoStub{deleteErr: deleteErr}

backend/internal/service/proxy.go

@@ -31,5 +31,16 @@ func (p *Proxy) URL() string {
 
 type ProxyWithAccountCount struct {
 	Proxy
-	AccountCount int64
+	AccountCount   int64
+	LatencyMs      *int64
+	LatencyStatus  string
+	LatencyMessage string
+}
+
+type ProxyAccountSummary struct {
+	ID       int64
+	Name     string
+	Platform string
+	Type     string
+	Notes    *string
 }

backend/internal/service/proxy_latency_cache.go

@@ -0,0 +1,18 @@
+package service
+
+import (
+	"context"
+	"time"
+)
+
+type ProxyLatencyInfo struct {
+	Success   bool      `json:"success"`
+	LatencyMs *int64    `json:"latency_ms,omitempty"`
+	Message   string    `json:"message,omitempty"`
+	UpdatedAt time.Time `json:"updated_at"`
+}
+
+type ProxyLatencyCache interface {
+	GetProxyLatencies(ctx context.Context, proxyIDs []int64) (map[int64]*ProxyLatencyInfo, error)
+	SetProxyLatency(ctx context.Context, proxyID int64, info *ProxyLatencyInfo) error
+}

backend/internal/service/proxy_service.go

@@ -10,6 +10,7 @@ import (
 
 var (
 	ErrProxyNotFound = infraerrors.NotFound("PROXY_NOT_FOUND", "proxy not found")
+	ErrProxyInUse    = infraerrors.Conflict("PROXY_IN_USE", "proxy is in use by accounts")
 )
 
 type ProxyRepository interface {
@@ -26,6 +27,7 @@ type ProxyRepository interface {
 
 	ExistsByHostPortAuth(ctx context.Context, host string, port int, username, password string) (bool, error)
 	CountAccountsByProxyID(ctx context.Context, proxyID int64) (int64, error)
+	ListAccountSummariesByProxyID(ctx context.Context, proxyID int64) ([]ProxyAccountSummary, error)
 }
 
 // CreateProxyRequest 创建代理请求