refactor: 使用行业标准方案重构服务重启逻辑

重构内容：
- 移除复杂的 sudo systemctl restart 方案
- 改用 os.Exit(0) + systemd Restart=always 的标准做法
- 删除 sudoers 配置及相关代码
- 删除 sub2api-sudoers 文件

优势：
- 代码从 85+ 行简化到 47 行
- 无需 sudo 权限配置
- 无需特殊用户 shell 配置
- 更简单、更可靠
- 符合行业最佳实践（Docker/K8s 等均采用此方案）

工作原理：
- 服务调用 os.Exit(0) 优雅退出
- systemd 检测到退出后自动重启（Restart=always）

.gitignore

@@ -91,4 +91,5 @@ backend/data/
 # ===================
 tests
 CLAUDE.md
-.claude
+.claude
+scripts

backend/internal/pkg/sysutil/restart.go

@@ -1,43 +1,39 @@
 package sysutil
 
 import (
-	"fmt"
 	"log"
-	"os/exec"
+	"os"
 	"runtime"
+	"time"
 )
 
-const serviceName = "sub2api"
-
-// RestartService triggers a service restart via systemd.
+// RestartService triggers a service restart by gracefully exiting.
 //
-// IMPORTANT: This function initiates the restart and returns immediately.
-// The actual restart happens asynchronously - the current process will be killed
-// by systemd and a new process will be started.
-//
-// We use Start() instead of Run() because:
-//   - systemctl restart will kill the current process first
-//   - Run() waits for completion, but the process dies before completion
-//   - Start() spawns the command independently, allowing systemd to handle the full cycle
+// This relies on systemd's Restart=always configuration to automatically
+// restart the service after it exits. This is the industry-standard approach:
+//   - Simple and reliable
+//   - No sudo permissions needed
+//   - No complex process management
+//   - Leverages systemd's native restart capability
 //
 // Prerequisites:
 //   - Linux OS with systemd
-//   - NOPASSWD sudo access configured (install.sh creates /etc/sudoers.d/sub2api)
+//   - Service configured with Restart=always in systemd unit file
 func RestartService() error {
 	if runtime.GOOS != "linux" {
-		return fmt.Errorf("systemd restart only available on Linux")
+		log.Println("Service restart via exit only works on Linux with systemd")
+		return nil
 	}
 
-	log.Println("Initiating service restart...")
+	log.Println("Initiating service restart by graceful exit...")
+	log.Println("systemd will automatically restart the service (Restart=always)")
 
-	// The sub2api user has NOPASSWD sudo access for systemctl commands
-	// (configured by install.sh in /etc/sudoers.d/sub2api).
-	cmd := exec.Command("sudo", "systemctl", "restart", serviceName)
-	if err := cmd.Start(); err != nil {
-		return fmt.Errorf("failed to initiate service restart: %w", err)
-	}
+	// Give a moment for logs to flush and response to be sent
+	go func() {
+		time.Sleep(100 * time.Millisecond)
+		os.Exit(0)
+	}()
 
-	log.Println("Service restart initiated successfully")
 	return nil
 }
 

backend/internal/service/gateway_service.go

@@ -35,25 +35,25 @@ const (
 
 // allowedHeaders 白名单headers（参考CRS项目）
 var allowedHeaders = map[string]bool{
-	"accept":                                  true,
-	"x-stainless-retry-count":                 true,
-	"x-stainless-timeout":                     true,
-	"x-stainless-lang":                        true,
-	"x-stainless-package-version":             true,
-	"x-stainless-os":                          true,
-	"x-stainless-arch":                        true,
-	"x-stainless-runtime":                     true,
-	"x-stainless-runtime-version":             true,
-	"x-stainless-helper-method":               true,
+	"accept":                                    true,
+	"x-stainless-retry-count":                   true,
+	"x-stainless-timeout":                       true,
+	"x-stainless-lang":                          true,
+	"x-stainless-package-version":               true,
+	"x-stainless-os":                            true,
+	"x-stainless-arch":                          true,
+	"x-stainless-runtime":                       true,
+	"x-stainless-runtime-version":               true,
+	"x-stainless-helper-method":                 true,
 	"anthropic-dangerous-direct-browser-access": true,
-	"anthropic-version":                       true,
-	"x-app":                                   true,
-	"anthropic-beta":                          true,
-	"accept-language":                         true,
-	"sec-fetch-mode":                          true,
-	"accept-encoding":                         true,
-	"user-agent":                              true,
-	"content-type":                            true,
+	"anthropic-version":                         true,
+	"x-app":                                     true,
+	"anthropic-beta":                            true,
+	"accept-language":                           true,
+	"sec-fetch-mode":                            true,
+	"accept-encoding":                           true,
+	"user-agent":                                true,
+	"content-type":                              true,
 }
 
 // ClaudeUsage 表示Claude API返回的usage信息
@@ -418,13 +418,19 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *m
 	}
 
 	// 构建上游请求
-	upstreamReq, err := s.buildUpstreamRequest(ctx, c, account, body, token, tokenType)
+	upstreamResult, err := s.buildUpstreamRequest(ctx, c, account, body, token, tokenType)
 	if err != nil {
 		return nil, err
 	}
 
+	// 选择使用的client：如果有代理则使用独立的client，否则使用共享的httpClient
+	httpClient := s.httpClient
+	if upstreamResult.Client != nil {
+		httpClient = upstreamResult.Client
+	}
+
 	// 发送请求
-	resp, err := s.httpClient.Do(upstreamReq)
+	resp, err := httpClient.Do(upstreamResult.Request)
 	if err != nil {
 		return nil, fmt.Errorf("upstream request failed: %w", err)
 	}
@@ -437,11 +443,16 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *m
 		if err != nil {
 			return nil, fmt.Errorf("token refresh failed: %w", err)
 		}
-		upstreamReq, err = s.buildUpstreamRequest(ctx, c, account, body, token, tokenType)
+		upstreamResult, err = s.buildUpstreamRequest(ctx, c, account, body, token, tokenType)
 		if err != nil {
 			return nil, err
 		}
-		resp, err = s.httpClient.Do(upstreamReq)
+		// 重试时也需要使用正确的client
+		httpClient = s.httpClient
+		if upstreamResult.Client != nil {
+			httpClient = upstreamResult.Client
+		}
+		resp, err = httpClient.Do(upstreamResult.Request)
 		if err != nil {
 			return nil, fmt.Errorf("retry request failed: %w", err)
 		}
@@ -480,7 +491,13 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *m
 	}, nil
 }
 
-func (s *GatewayService) buildUpstreamRequest(ctx context.Context, c *gin.Context, account *model.Account, body []byte, token, tokenType string) (*http.Request, error) {
+// buildUpstreamRequestResult contains the request and optional custom client for proxy
+type buildUpstreamRequestResult struct {
+	Request *http.Request
+	Client  *http.Client // nil means use default s.httpClient
+}
+
+func (s *GatewayService) buildUpstreamRequest(ctx context.Context, c *gin.Context, account *model.Account, body []byte, token, tokenType string) (*buildUpstreamRequestResult, error) {
 	// 确定目标URL
 	targetURL := claudeAPIURL
 	if account.Type == model.AccountTypeApiKey {
@@ -549,7 +566,8 @@ func (s *GatewayService) buildUpstreamRequest(ctx context.Context, c *gin.Contex
 		req.Header.Set("anthropic-beta", s.getBetaHeader(body, c.GetHeader("anthropic-beta")))
 	}
 
-	// 配置代理
+	// 配置代理 - 创建独立的client避免并发修改共享httpClient
+	var customClient *http.Client
 	if account.ProxyID != nil && account.Proxy != nil {
 		proxyURL := account.Proxy.URL()
 		if proxyURL != "" {
@@ -566,12 +584,18 @@ func (s *GatewayService) buildUpstreamRequest(ctx context.Context, c *gin.Contex
 					IdleConnTimeout:       90 * time.Second,
 					ResponseHeaderTimeout: responseHeaderTimeout,
 				}
-				s.httpClient.Transport = transport
+				// 创建独立的client，避免并发时修改共享的s.httpClient.Transport
+				customClient = &http.Client{
+					Transport: transport,
+				}
 			}
 		}
 	}
 
-	return req, nil
+	return &buildUpstreamRequestResult{
+		Request: req,
+		Client:  customClient,
+	}, nil
 }
 
 // getBetaHeader 处理anthropic-beta header

deploy/install.sh

@@ -73,9 +73,6 @@ declare -A MSG_ZH=(
     ["dirs_configured"]="目录配置完成"
     ["installing_service"]="正在安装 systemd 服务..."
     ["service_installed"]="systemd 服务已安装"
-    ["setting_up_sudoers"]="正在配置 sudoers..."
-    ["sudoers_configured"]="sudoers 配置完成"
-    ["sudoers_failed"]="sudoers 验证失败，已移除文件"
     ["ready_for_setup"]="准备就绪，可以启动设置向导"
 
     # Completion
@@ -173,9 +170,6 @@ declare -A MSG_EN=(
     ["dirs_configured"]="Directories configured"
     ["installing_service"]="Installing systemd service..."
     ["service_installed"]="Systemd service installed"
-    ["setting_up_sudoers"]="Setting up sudoers..."
-    ["sudoers_configured"]="Sudoers configured"
-    ["sudoers_failed"]="Sudoers validation failed, removing file"
     ["ready_for_setup"]="Ready for Setup Wizard"
 
     # Completion
@@ -483,9 +477,24 @@ download_and_extract() {
 create_user() {
     if id "$SERVICE_USER" &>/dev/null; then
         print_info "$(msg 'user_exists'): $SERVICE_USER"
+        # Fix: Ensure existing user has /bin/sh shell for sudo to work
+        # Previous versions used /bin/false which prevents sudo execution
+        local current_shell
+        current_shell=$(getent passwd "$SERVICE_USER" 2>/dev/null | cut -d: -f7)
+        if [ "$current_shell" = "/bin/false" ] || [ "$current_shell" = "/sbin/nologin" ]; then
+            print_info "Fixing user shell for sudo compatibility..."
+            if usermod -s /bin/sh "$SERVICE_USER" 2>/dev/null; then
+                print_success "User shell updated to /bin/sh"
+            else
+                print_warning "Failed to update user shell. Service restart may not work automatically."
+                print_warning "Manual fix: sudo usermod -s /bin/sh $SERVICE_USER"
+            fi
+        fi
     else
         print_info "$(msg 'creating_user') $SERVICE_USER..."
-        useradd -r -s /bin/false -d "$INSTALL_DIR" "$SERVICE_USER"
+        # Use /bin/sh instead of /bin/false to allow sudo execution
+        # The user still cannot login interactively (no password set)
+        useradd -r -s /bin/sh -d "$INSTALL_DIR" "$SERVICE_USER"
         print_success "$(msg 'user_created')"
     fi
 }
@@ -506,35 +515,6 @@ setup_directories() {
     print_success "$(msg 'dirs_configured')"
 }
 
-# Setup sudoers for service restart
-setup_sudoers() {
-    print_info "$(msg 'setting_up_sudoers')"
-
-    # Check if sudoers file exists in install dir
-    if [ -f "$INSTALL_DIR/sub2api-sudoers" ]; then
-        cp "$INSTALL_DIR/sub2api-sudoers" /etc/sudoers.d/sub2api
-    else
-        # Create sudoers file
-        cat > /etc/sudoers.d/sub2api << 'EOF'
-# Sudoers configuration for Sub2API
-sub2api ALL=(ALL) NOPASSWD: /bin/systemctl restart sub2api
-sub2api ALL=(ALL) NOPASSWD: /bin/systemctl stop sub2api
-sub2api ALL=(ALL) NOPASSWD: /bin/systemctl start sub2api
-EOF
-    fi
-
-    # Set correct permissions (required for sudoers files)
-    chmod 440 /etc/sudoers.d/sub2api
-
-    # Validate sudoers file
-    if visudo -c -f /etc/sudoers.d/sub2api &>/dev/null; then
-        print_success "$(msg 'sudoers_configured')"
-    else
-        print_warning "$(msg 'sudoers_failed')"
-        rm -f /etc/sudoers.d/sub2api
-    fi
-}
-
 # Install systemd service
 install_service() {
     print_info "$(msg 'installing_service')"
@@ -701,7 +681,6 @@ uninstall() {
 
     print_info "$(msg 'removing_files')"
     rm -f /etc/systemd/system/sub2api.service
-    rm -f /etc/sudoers.d/sub2api
     systemctl daemon-reload
 
     print_info "$(msg 'removing_install_dir')"
@@ -772,7 +751,6 @@ main() {
     create_user
     setup_directories
     install_service
-    setup_sudoers
     prepare_for_setup
     print_completion
 }

deploy/sub2api-sudoers

@@ -1,13 +0,0 @@
-# Sudoers configuration for Sub2API
-# This file allows the sub2api service user to restart the service without password
-#
-# Installation:
-#   sudo cp sub2api-sudoers /etc/sudoers.d/sub2api
-#   sudo chmod 440 /etc/sudoers.d/sub2api
-#
-# SECURITY NOTE: This grants limited sudo access only for service management
-
-# Allow sub2api user to restart the service without password
-sub2api ALL=(ALL) NOPASSWD: /bin/systemctl restart sub2api
-sub2api ALL=(ALL) NOPASSWD: /bin/systemctl stop sub2api
-sub2api ALL=(ALL) NOPASSWD: /bin/systemctl start sub2api