Added daemon mode

cmd/mcp.go

@@ -2,6 +2,10 @@ package root
 
 import (
 	"fmt"
+	"os"
+	"os/exec"
+	"os/signal"
+	"syscall"
 
 	"github.com/inercia/MCPShell/pkg/common"
 	"github.com/inercia/MCPShell/pkg/config"
@@ -13,6 +17,7 @@ import (
 var (
 	useHTTP  bool
 	httpPort int
+	daemon   bool
 )
 
 // mcpCommand represents the run command which starts the MCP server
@@ -25,8 +30,11 @@ Run an MCP server that provides tools to LLM applications.
 This command starts a server that communicates using the Model Context Protocol (MCP)
 and expooses the tools defined in a MCP configuration file.
 
-The server loads tool definitions from a YAML configuration file and makes them
+The server loads tool definitions from a MCP configuration file and makes them
 available to AI applications via the MCP protocol.
+
+When using --http mode, you can also use --daemon to run the server in the background
+and ignore SIGHUP signals.
 `,
 	PreRunE: func(cmd *cobra.Command, args []string) error {
 		// Initialize logger
@@ -51,12 +59,27 @@ available to AI applications via the MCP protocol.
 			return fmt.Errorf("failed to ensure tools directory: %w", err)
 		}
 
+		// Daemon mode is only supported with HTTP mode
+		if daemon && !useHTTP {
+			logger.Error("Daemon mode is only supported with HTTP mode")
+			return fmt.Errorf("daemon mode is only supported with HTTP mode (use --http flag)")
+		}
+
 		return nil
 	},
 	RunE: func(cmd *cobra.Command, args []string) error {
 		logger := common.GetLogger()
 		defer common.RecoverPanic()
 
+		// Daemonize if requested
+		if daemon {
+			if err := daemonize(); err != nil {
+				logger.Error("Failed to daemonize: %v", err)
+				return fmt.Errorf("failed to daemonize: %w", err)
+			}
+			logger.Info("Daemonized successfully")
+		}
+
 		// Load the configuration file(s) (local or remote)
 		localConfigPath, cleanup, err := config.ResolveMultipleConfigPaths(toolsFiles, logger)
 		if err != nil {
@@ -78,12 +101,82 @@ available to AI applications via the MCP protocol.
 		})
 
 		if useHTTP {
+			// Set up SIGHUP handling for daemon mode
+			if daemon {
+				setupSIGHUPHandler(logger)
+			}
 			return srv.StartHTTP(httpPort)
 		}
 		return srv.Start()
 	},
 }
 
+// daemonize forks the process to run in the background
+func daemonize() error {
+	// Get the current executable path
+	executable, err := os.Executable()
+	if err != nil {
+		return fmt.Errorf("failed to get executable path: %w", err)
+	}
+
+	// Get current working directory
+	workDir, err := os.Getwd()
+	if err != nil {
+		return fmt.Errorf("failed to get working directory: %w", err)
+	}
+
+	// Build command arguments, excluding the daemon flag
+	args := os.Args[1:]
+	var newArgs []string
+	for i, arg := range args {
+		if arg == "--daemon" {
+			// Skip the daemon flag
+			continue
+		}
+		if i > 0 && args[i-1] == "--daemon" {
+			// Skip the value if it was a separate argument
+			continue
+		}
+		newArgs = append(newArgs, arg)
+	}
+
+	// Create the command
+	cmd := exec.Command(executable, newArgs...)
+	cmd.Dir = workDir
+	cmd.Env = os.Environ()
+
+	// Set up process attributes for daemon behavior
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Setsid: true, // Create new session
+	}
+
+	// Start the process
+	if err := cmd.Start(); err != nil {
+		return fmt.Errorf("failed to start daemon process: %w", err)
+	}
+
+	// Exit the parent process
+	os.Exit(0)
+
+	// This line should never be reached, but Go requires it
+	return nil
+}
+
+// setupSIGHUPHandler sets up signal handling to ignore SIGHUP in daemon mode
+func setupSIGHUPHandler(logger *common.Logger) {
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGHUP)
+
+	go func() {
+		for {
+			sig := <-sigChan
+			if sig == syscall.SIGHUP {
+				logger.Info("Received SIGHUP, ignoring in daemon mode")
+			}
+		}
+	}()
+}
+
 // init adds flags to the run command
 func init() {
 	rootCmd.AddCommand(mcpCommand)
@@ -96,6 +189,7 @@ func init() {
 	// Add HTTP server flags
 	mcpCommand.Flags().BoolVar(&useHTTP, "http", false, "Enable HTTP server mode (serve MCP over HTTP/SSE instead of stdio)")
 	mcpCommand.Flags().IntVar(&httpPort, "port", 8080, "Port for HTTP server (default: 8080, only used with --http)")
+	mcpCommand.Flags().BoolVar(&daemon, "daemon", false, "Run in daemon mode (background process, ignores SIGHUP, only works with --http)")
 
 	// Mark required flags
 	_ = mcpCommand.MarkFlagRequired("tools")

docs/usage.md

@@ -103,11 +103,12 @@ Runs an MCP server that communicates using the Model Context Protocol and expose
 
 - `--http`: Enable HTTP server mode (serve MCP over HTTP/SSE instead of stdio)
 - `--port`: Port for HTTP server (default: 8080, only used with --http)
+- `--daemon`: Run in daemon mode (background process, ignores SIGHUP, only works with --http)
 
 **Example**:
 
 ```console
-mcpshell mcp --tools=examples/config.yaml --log-level=debug
+mcpshell mcp --tools=examples/config.yaml --http --port=9090 --daemon --log-level=debug
 ```
 
 ### EXE Command