refactor(logging): replace log.Fatalf with log.Errorf and add error handling paths

cmd/server/main.go

@@ -139,7 +139,8 @@ func main() {
 
 	wd, err := os.Getwd()
 	if err != nil {
-		log.Fatalf("failed to get working directory: %v", err)
+		log.Errorf("failed to get working directory: %v", err)
+		return
 	}
 
 	// Load environment variables from .env if present.
@@ -233,13 +234,15 @@ func main() {
 		})
 		cancel()
 		if err != nil {
-			log.Fatalf("failed to initialize postgres token store: %v", err)
+			log.Errorf("failed to initialize postgres token store: %v", err)
+			return
 		}
 		examplePath := filepath.Join(wd, "config.example.yaml")
 		ctx, cancel = context.WithTimeout(context.Background(), 30*time.Second)
 		if errBootstrap := pgStoreInst.Bootstrap(ctx, examplePath); errBootstrap != nil {
 			cancel()
-			log.Fatalf("failed to bootstrap postgres-backed config: %v", errBootstrap)
+			log.Errorf("failed to bootstrap postgres-backed config: %v", errBootstrap)
+			return
 		}
 		cancel()
 		configFilePath = pgStoreInst.ConfigPath()
@@ -262,7 +265,8 @@ func main() {
 		if strings.Contains(resolvedEndpoint, "://") {
 			parsed, errParse := url.Parse(resolvedEndpoint)
 			if errParse != nil {
-				log.Fatalf("failed to parse object store endpoint %q: %v", objectStoreEndpoint, errParse)
+				log.Errorf("failed to parse object store endpoint %q: %v", objectStoreEndpoint, errParse)
+				return
 			}
 			switch strings.ToLower(parsed.Scheme) {
 			case "http":
@@ -270,10 +274,12 @@ func main() {
 			case "https":
 				useSSL = true
 			default:
-				log.Fatalf("unsupported object store scheme %q (only http and https are allowed)", parsed.Scheme)
+				log.Errorf("unsupported object store scheme %q (only http and https are allowed)", parsed.Scheme)
+				return
 			}
 			if parsed.Host == "" {
-				log.Fatalf("object store endpoint %q is missing host information", objectStoreEndpoint)
+				log.Errorf("object store endpoint %q is missing host information", objectStoreEndpoint)
+				return
 			}
 			resolvedEndpoint = parsed.Host
 			if parsed.Path != "" && parsed.Path != "/" {
@@ -292,13 +298,15 @@ func main() {
 		}
 		objectStoreInst, err = store.NewObjectTokenStore(objCfg)
 		if err != nil {
-			log.Fatalf("failed to initialize object token store: %v", err)
+			log.Errorf("failed to initialize object token store: %v", err)
+			return
 		}
 		examplePath := filepath.Join(wd, "config.example.yaml")
 		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 		if errBootstrap := objectStoreInst.Bootstrap(ctx, examplePath); errBootstrap != nil {
 			cancel()
-			log.Fatalf("failed to bootstrap object-backed config: %v", errBootstrap)
+			log.Errorf("failed to bootstrap object-backed config: %v", errBootstrap)
+			return
 		}
 		cancel()
 		configFilePath = objectStoreInst.ConfigPath()
@@ -323,7 +331,8 @@ func main() {
 		gitStoreInst = store.NewGitTokenStore(gitStoreRemoteURL, gitStoreUser, gitStorePassword)
 		gitStoreInst.SetBaseDir(authDir)
 		if errRepo := gitStoreInst.EnsureRepository(); errRepo != nil {
-			log.Fatalf("failed to prepare git token store: %v", errRepo)
+			log.Errorf("failed to prepare git token store: %v", errRepo)
+			return
 		}
 		configFilePath = gitStoreInst.ConfigPath()
 		if configFilePath == "" {
@@ -332,17 +341,21 @@ func main() {
 		if _, statErr := os.Stat(configFilePath); errors.Is(statErr, fs.ErrNotExist) {
 			examplePath := filepath.Join(wd, "config.example.yaml")
 			if _, errExample := os.Stat(examplePath); errExample != nil {
-				log.Fatalf("failed to find template config file: %v", errExample)
+				log.Errorf("failed to find template config file: %v", errExample)
+				return
 			}
 			if errCopy := misc.CopyConfigTemplate(examplePath, configFilePath); errCopy != nil {
-				log.Fatalf("failed to bootstrap git-backed config: %v", errCopy)
+				log.Errorf("failed to bootstrap git-backed config: %v", errCopy)
+				return
 			}
 			if errCommit := gitStoreInst.PersistConfig(context.Background()); errCommit != nil {
-				log.Fatalf("failed to commit initial git-backed config: %v", errCommit)
+				log.Errorf("failed to commit initial git-backed config: %v", errCommit)
+				return
 			}
 			log.Infof("git-backed config initialized from template: %s", configFilePath)
 		} else if statErr != nil {
-			log.Fatalf("failed to inspect git-backed config: %v", statErr)
+			log.Errorf("failed to inspect git-backed config: %v", statErr)
+			return
 		}
 		cfg, err = config.LoadConfigOptional(configFilePath, isCloudDeploy)
 		if err == nil {
@@ -355,13 +368,15 @@ func main() {
 	} else {
 		wd, err = os.Getwd()
 		if err != nil {
-			log.Fatalf("failed to get working directory: %v", err)
+			log.Errorf("failed to get working directory: %v", err)
+			return
 		}
 		configFilePath = filepath.Join(wd, "config.yaml")
 		cfg, err = config.LoadConfigOptional(configFilePath, isCloudDeploy)
 	}
 	if err != nil {
-		log.Fatalf("failed to load config: %v", err)
+		log.Errorf("failed to load config: %v", err)
+		return
 	}
 	if cfg == nil {
 		cfg = &config.Config{}
@@ -391,7 +406,8 @@ func main() {
 	coreauth.SetQuotaCooldownDisabled(cfg.DisableCooling)
 
 	if err = logging.ConfigureLogOutput(cfg.LoggingToFile); err != nil {
-		log.Fatalf("failed to configure log output: %v", err)
+		log.Errorf("failed to configure log output: %v", err)
+		return
 	}
 
 	log.Infof("CLIProxyAPI Version: %s, Commit: %s, BuiltAt: %s", buildinfo.Version, buildinfo.Commit, buildinfo.BuildDate)
@@ -400,7 +416,8 @@ func main() {
 	util.SetLogLevel(cfg)
 
 	if resolvedAuthDir, errResolveAuthDir := util.ResolveAuthDir(cfg.AuthDir); errResolveAuthDir != nil {
-		log.Fatalf("failed to resolve auth directory: %v", errResolveAuthDir)
+		log.Errorf("failed to resolve auth directory: %v", errResolveAuthDir)
+		return
 	} else {
 		cfg.AuthDir = resolvedAuthDir
 	}

internal/api/handlers/management/auth_files.go

@@ -713,14 +713,16 @@ func (h *Handler) RequestAnthropicToken(c *gin.Context) {
 	// Generate PKCE codes
 	pkceCodes, err := claude.GeneratePKCECodes()
 	if err != nil {
-		log.Fatalf("Failed to generate PKCE codes: %v", err)
+		log.Errorf("Failed to generate PKCE codes: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate PKCE codes"})
 		return
 	}
 
 	// Generate random state parameter
 	state, err := misc.GenerateRandomState()
 	if err != nil {
-		log.Fatalf("Failed to generate state parameter: %v", err)
+		log.Errorf("Failed to generate state parameter: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate state parameter"})
 		return
 	}
 
@@ -730,7 +732,8 @@ func (h *Handler) RequestAnthropicToken(c *gin.Context) {
 	// Generate authorization URL (then override redirect_uri to reuse server port)
 	authURL, state, err := anthropicAuth.GenerateAuthURL(state, pkceCodes)
 	if err != nil {
-		log.Fatalf("Failed to generate authorization URL: %v", err)
+		log.Errorf("Failed to generate authorization URL: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate authorization url"})
 		return
 	}
 
@@ -872,7 +875,7 @@ func (h *Handler) RequestAnthropicToken(c *gin.Context) {
 		}
 		savedPath, errSave := h.saveTokenRecord(ctx, record)
 		if errSave != nil {
-			log.Fatalf("Failed to save authentication tokens: %v", errSave)
+			log.Errorf("Failed to save authentication tokens: %v", errSave)
 			oauthStatus[state] = "Failed to save authentication tokens"
 			return
 		}
@@ -1045,7 +1048,7 @@ func (h *Handler) RequestGeminiCLIToken(c *gin.Context) {
 		gemAuth := geminiAuth.NewGeminiAuth()
 		gemClient, errGetClient := gemAuth.GetAuthenticatedClient(ctx, &ts, h.cfg, true)
 		if errGetClient != nil {
-			log.Fatalf("failed to get authenticated client: %v", errGetClient)
+			log.Errorf("failed to get authenticated client: %v", errGetClient)
 			oauthStatus[state] = "Failed to get authenticated client"
 			return
 		}
@@ -1110,7 +1113,7 @@ func (h *Handler) RequestGeminiCLIToken(c *gin.Context) {
 		}
 		savedPath, errSave := h.saveTokenRecord(ctx, record)
 		if errSave != nil {
-			log.Fatalf("Failed to save token to file: %v", errSave)
+			log.Errorf("Failed to save token to file: %v", errSave)
 			oauthStatus[state] = "Failed to save token to file"
 			return
 		}
@@ -1131,14 +1134,16 @@ func (h *Handler) RequestCodexToken(c *gin.Context) {
 	// Generate PKCE codes
 	pkceCodes, err := codex.GeneratePKCECodes()
 	if err != nil {
-		log.Fatalf("Failed to generate PKCE codes: %v", err)
+		log.Errorf("Failed to generate PKCE codes: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate PKCE codes"})
 		return
 	}
 
 	// Generate random state parameter
 	state, err := misc.GenerateRandomState()
 	if err != nil {
-		log.Fatalf("Failed to generate state parameter: %v", err)
+		log.Errorf("Failed to generate state parameter: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate state parameter"})
 		return
 	}
 
@@ -1148,7 +1153,8 @@ func (h *Handler) RequestCodexToken(c *gin.Context) {
 	// Generate authorization URL
 	authURL, err := openaiAuth.GenerateAuthURL(state, pkceCodes)
 	if err != nil {
-		log.Fatalf("Failed to generate authorization URL: %v", err)
+		log.Errorf("Failed to generate authorization URL: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate authorization url"})
 		return
 	}
 
@@ -1283,7 +1289,7 @@ func (h *Handler) RequestCodexToken(c *gin.Context) {
 		savedPath, errSave := h.saveTokenRecord(ctx, record)
 		if errSave != nil {
 			oauthStatus[state] = "Failed to save authentication tokens"
-			log.Fatalf("Failed to save authentication tokens: %v", errSave)
+			log.Errorf("Failed to save authentication tokens: %v", errSave)
 			return
 		}
 		fmt.Printf("Authentication successful! Token saved to %s\n", savedPath)
@@ -1318,7 +1324,8 @@ func (h *Handler) RequestAntigravityToken(c *gin.Context) {
 
 	state, errState := misc.GenerateRandomState()
 	if errState != nil {
-		log.Fatalf("Failed to generate state parameter: %v", errState)
+		log.Errorf("Failed to generate state parameter: %v", errState)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate state parameter"})
 		return
 	}
 
@@ -1514,7 +1521,7 @@ func (h *Handler) RequestAntigravityToken(c *gin.Context) {
 		}
 		savedPath, errSave := h.saveTokenRecord(ctx, record)
 		if errSave != nil {
-			log.Fatalf("Failed to save token to file: %v", errSave)
+			log.Errorf("Failed to save token to file: %v", errSave)
 			oauthStatus[state] = "Failed to save token to file"
 			return
 		}
@@ -1543,7 +1550,8 @@ func (h *Handler) RequestQwenToken(c *gin.Context) {
 	// Generate authorization URL
 	deviceFlow, err := qwenAuth.InitiateDeviceFlow(ctx)
 	if err != nil {
-		log.Fatalf("Failed to generate authorization URL: %v", err)
+		log.Errorf("Failed to generate authorization URL: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to generate authorization url"})
 		return
 	}
 	authURL := deviceFlow.VerificationURIComplete
@@ -1570,7 +1578,7 @@ func (h *Handler) RequestQwenToken(c *gin.Context) {
 		}
 		savedPath, errSave := h.saveTokenRecord(ctx, record)
 		if errSave != nil {
-			log.Fatalf("Failed to save authentication tokens: %v", errSave)
+			log.Errorf("Failed to save authentication tokens: %v", errSave)
 			oauthStatus[state] = "Failed to save authentication tokens"
 			return
 		}
@@ -1674,7 +1682,7 @@ func (h *Handler) RequestIFlowToken(c *gin.Context) {
 		savedPath, errSave := h.saveTokenRecord(ctx, record)
 		if errSave != nil {
 			oauthStatus[state] = "Failed to save authentication tokens"
-			log.Fatalf("Failed to save authentication tokens: %v", errSave)
+			log.Errorf("Failed to save authentication tokens: %v", errSave)
 			return
 		}
 
@@ -2103,6 +2111,7 @@ func checkCloudAPIIsEnabled(ctx context.Context, httpClient *http.Client, projec
 				continue
 			}
 		}
+		_ = resp.Body.Close()
 		return false, fmt.Errorf("project activation required: %s", errMessage)
 	}
 	return true, nil

internal/auth/gemini/gemini_auth.go

@@ -76,7 +76,8 @@ func (g *GeminiAuth) GetAuthenticatedClient(ctx context.Context, ts *GeminiToken
 			auth := &proxy.Auth{User: username, Password: password}
 			dialer, errSOCKS5 := proxy.SOCKS5("tcp", proxyURL.Host, auth, proxy.Direct)
 			if errSOCKS5 != nil {
-				log.Fatalf("create SOCKS5 dialer failed: %v", errSOCKS5)
+				log.Errorf("create SOCKS5 dialer failed: %v", errSOCKS5)
+				return nil, fmt.Errorf("create SOCKS5 dialer failed: %w", errSOCKS5)
 			}
 			transport = &http.Transport{
 				DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
@@ -238,7 +239,11 @@ func (g *GeminiAuth) getTokenFromWeb(ctx context.Context, config *oauth2.Config,
 	// Start the server in a goroutine.
 	go func() {
 		if err := server.ListenAndServe(); !errors.Is(err, http.ErrServerClosed) {
-			log.Fatalf("ListenAndServe(): %v", err)
+			log.Errorf("ListenAndServe(): %v", err)
+			select {
+			case errChan <- err:
+			default:
+			}
 		}
 	}()
 

internal/cmd/login.go

@@ -65,20 +65,20 @@ func DoLogin(cfg *config.Config, projectID string, options *LoginOptions) {
 	authenticator := sdkAuth.NewGeminiAuthenticator()
 	record, errLogin := authenticator.Login(ctx, cfg, loginOpts)
 	if errLogin != nil {
-		log.Fatalf("Gemini authentication failed: %v", errLogin)
+		log.Errorf("Gemini authentication failed: %v", errLogin)
 		return
 	}
 
 	storage, okStorage := record.Storage.(*gemini.GeminiTokenStorage)
 	if !okStorage || storage == nil {
-		log.Fatal("Gemini authentication failed: unsupported token storage")
+		log.Error("Gemini authentication failed: unsupported token storage")
 		return
 	}
 
 	geminiAuth := gemini.NewGeminiAuth()
 	httpClient, errClient := geminiAuth.GetAuthenticatedClient(ctx, storage, cfg, options.NoBrowser)
 	if errClient != nil {
-		log.Fatalf("Gemini authentication failed: %v", errClient)
+		log.Errorf("Gemini authentication failed: %v", errClient)
 		return
 	}
 
@@ -86,7 +86,7 @@ func DoLogin(cfg *config.Config, projectID string, options *LoginOptions) {
 
 	projects, errProjects := fetchGCPProjects(ctx, httpClient)
 	if errProjects != nil {
-		log.Fatalf("Failed to get project list: %v", errProjects)
+		log.Errorf("Failed to get project list: %v", errProjects)
 		return
 	}
 
@@ -98,11 +98,11 @@ func DoLogin(cfg *config.Config, projectID string, options *LoginOptions) {
 	selectedProjectID := promptForProjectSelection(projects, strings.TrimSpace(projectID), promptFn)
 	projectSelections, errSelection := resolveProjectSelections(selectedProjectID, projects)
 	if errSelection != nil {
-		log.Fatalf("Invalid project selection: %v", errSelection)
+		log.Errorf("Invalid project selection: %v", errSelection)
 		return
 	}
 	if len(projectSelections) == 0 {
-		log.Fatal("No project selected; aborting login.")
+		log.Error("No project selected; aborting login.")
 		return
 	}
 
@@ -116,7 +116,7 @@ func DoLogin(cfg *config.Config, projectID string, options *LoginOptions) {
 				showProjectSelectionHelp(storage.Email, projects)
 				return
 			}
-			log.Fatalf("Failed to complete user setup: %v", errSetup)
+			log.Errorf("Failed to complete user setup: %v", errSetup)
 			return
 		}
 		finalID := strings.TrimSpace(storage.ProjectID)
@@ -133,11 +133,11 @@ func DoLogin(cfg *config.Config, projectID string, options *LoginOptions) {
 		for _, pid := range activatedProjects {
 			isChecked, errCheck := checkCloudAPIIsEnabled(ctx, httpClient, pid)
 			if errCheck != nil {
-				log.Fatalf("Failed to check if Cloud AI API is enabled for %s: %v", pid, errCheck)
+				log.Errorf("Failed to check if Cloud AI API is enabled for %s: %v", pid, errCheck)
 				return
 			}
 			if !isChecked {
-				log.Fatalf("Failed to check if Cloud AI API is enabled for project %s. If you encounter an error message, please create an issue.", pid)
+				log.Errorf("Failed to check if Cloud AI API is enabled for project %s. If you encounter an error message, please create an issue.", pid)
 				return
 			}
 		}
@@ -153,7 +153,7 @@ func DoLogin(cfg *config.Config, projectID string, options *LoginOptions) {
 
 	savedPath, errSave := store.Save(ctx, record)
 	if errSave != nil {
-		log.Fatalf("Failed to save token to file: %v", errSave)
+		log.Errorf("Failed to save token to file: %v", errSave)
 		return
 	}
 
@@ -555,6 +555,7 @@ func checkCloudAPIIsEnabled(ctx context.Context, httpClient *http.Client, projec
 				continue
 			}
 		}
+		_ = resp.Body.Close()
 		return false, fmt.Errorf("project activation required: %s", errMessage)
 	}
 	return true, nil

internal/cmd/run.go

@@ -45,12 +45,13 @@ func StartService(cfg *config.Config, configPath string, localPassword string) {
 
 	service, err := builder.Build()
 	if err != nil {
-		log.Fatalf("failed to build proxy service: %v", err)
+		log.Errorf("failed to build proxy service: %v", err)
+		return
 	}
 
 	err = service.Run(runCtx)
 	if err != nil && !errors.Is(err, context.Canceled) {
-		log.Fatalf("proxy service exited with error: %v", err)
+		log.Errorf("proxy service exited with error: %v", err)
 	}
 }
 

internal/cmd/vertex_import.go

@@ -29,30 +29,30 @@ func DoVertexImport(cfg *config.Config, keyPath string) {
 	}
 	rawPath := strings.TrimSpace(keyPath)
 	if rawPath == "" {
-		log.Fatalf("vertex-import: missing service account key path")
+		log.Errorf("vertex-import: missing service account key path")
 		return
 	}
 	data, errRead := os.ReadFile(rawPath)
 	if errRead != nil {
-		log.Fatalf("vertex-import: read file failed: %v", errRead)
+		log.Errorf("vertex-import: read file failed: %v", errRead)
 		return
 	}
 	var sa map[string]any
 	if errUnmarshal := json.Unmarshal(data, &sa); errUnmarshal != nil {
-		log.Fatalf("vertex-import: invalid service account json: %v", errUnmarshal)
+		log.Errorf("vertex-import: invalid service account json: %v", errUnmarshal)
 		return
 	}
 	// Validate and normalize private_key before saving
 	normalizedSA, errFix := vertex.NormalizeServiceAccountMap(sa)
 	if errFix != nil {
-		log.Fatalf("vertex-import: %v", errFix)
+		log.Errorf("vertex-import: %v", errFix)
 		return
 	}
 	sa = normalizedSA
 	email, _ := sa["client_email"].(string)
 	projectID, _ := sa["project_id"].(string)
 	if strings.TrimSpace(projectID) == "" {
-		log.Fatalf("vertex-import: project_id missing in service account json")
+		log.Errorf("vertex-import: project_id missing in service account json")
 		return
 	}
 	if strings.TrimSpace(email) == "" {
@@ -92,7 +92,7 @@ func DoVertexImport(cfg *config.Config, keyPath string) {
 	}
 	path, errSave := store.Save(context.Background(), record)
 	if errSave != nil {
-		log.Fatalf("vertex-import: save credential failed: %v", errSave)
+		log.Errorf("vertex-import: save credential failed: %v", errSave)
 		return
 	}
 	fmt.Printf("Vertex credentials imported: %s\n", path)