Go: add volcengine (#14409)

### What problem does this PR solve?

1. Refactor server_main
2. Add volcengine

### Type of change

- [x] Refactoring

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

cmd/admin_server.go

@@ -18,6 +18,7 @@ package main
 
 import (
 	"context"
+	"errors"
 	"flag"
 	"fmt"
 	"net/http"
@@ -38,15 +39,6 @@ import (
 	"ragflow/internal/utility"
 )
 
-// AdminServer admin server
-type AdminServer struct {
-	router  *admin.Router
-	handler *admin.Handler
-	service *admin.Service
-	engine  *gin.Engine
-	port    string
-}
-
 func main() {
 	var configPath string
 	flag.StringVar(&configPath, "config", "", "Path to configuration file")
@@ -161,7 +153,7 @@ func main() {
 	go func() {
 		logger.Info(fmt.Sprintf("Admin Go Version: %s", utility.GetRAGFlowVersion()))
 		logger.Info(fmt.Sprintf("Starting RAGFlow admin server on port: %d", cfg.Admin.Port))
-		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+		if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
 			logger.Fatal("Failed to start server", zap.Error(err))
 		}
 	}()

cmd/server_main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"errors"
 	"flag"
 	"fmt"
 	"net/http"
@@ -65,23 +66,22 @@ func main() {
 	}
 
 	// Override port with command line argument if provided
+	config := server.GetConfig()
 	if portFlag > 0 {
-		config := server.GetConfig()
 		config.Server.Port = portFlag
 		logger.Info("Port overridden by command line argument", zap.Int("port", portFlag))
 	}
 
+	if config.Server.Port == 0 {
+		logger.Fatal("Server port is not configured. Please specify via --port flag or config file.")
+	}
+
 	// Load model providers configuration
 	if err := server.LoadModelProviders(""); err != nil {
 		logger.Fatal("Failed to load model providers", zap.Error(err))
 	}
 	logger.Info("Model providers loaded", zap.Int("count", len(server.GetModelProviders())))
 
-	config := server.GetConfig()
-	if config.Server.Port == 0 {
-		logger.Fatal("Server port is not configured. Please specify via --port flag or config file.")
-	}
-
 	// Reinitialize logger with configured level if different
 	if config.Log.Level != "" && config.Log.Level != "info" {
 		if err := logger.Init(config.Log.Level); err != nil {
@@ -232,15 +232,15 @@ func startServer(config *server.Config) {
 		)
 		logger.Info(fmt.Sprintf("RAGFlow Go Version: %s", utility.GetRAGFlowVersion()))
 		logger.Info(fmt.Sprintf("Server starting on port: %d", config.Server.Port))
-		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+		if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
 			logger.Fatal("Failed to start server", zap.Error(err))
 		}
 	}()
 
 	// Get local IP address for heartbeat reporting
-	localIP := utility.GetLocalIP()
-	if localIP == "" {
-		localIP = "127.0.0.1"
+	localIP, err := utility.GetLocalIP()
+	if err != nil {
+		logger.Fatal("fail to get local ip address")
 	}
 
 	// Initialize and start heartbeat reporter to admin server
@@ -251,7 +251,7 @@ func startServer(config *server.Config) {
 		localIP,
 		config.Server.Port,
 	)
-	if err := heartbeatService.InitHTTPClient(); err != nil {
+	if err = heartbeatService.InitHTTPClient(); err != nil {
 		logger.Warn("Failed to initialize heartbeat service", zap.Error(err))
 	} else {
 		// Start heartbeat reporter with 30 seconds interval
@@ -280,7 +280,7 @@ func startServer(config *server.Config) {
 	defer cancel()
 
 	// Shutdown server
-	if err := srv.Shutdown(ctx); err != nil {
+	if err = srv.Shutdown(ctx); err != nil {
 		logger.Fatal("Server forced to shutdown", zap.Error(err))
 	}
 }