feat: implement basic IPC mechanism

cmd/root/root.go

@@ -1,8 +1,16 @@
 package root
 
 import (
-	"context"
+	"bufio"
+	"errors"
+	"fmt"
+	"github.com/rs/zerolog"
+	"io"
+	"net"
 	"os"
+	"os/signal"
+	"strings"
+	"syscall"
 
 	"github.com/bilalcaliskan/split-the-tunnel/cmd/root/options"
 
@@ -27,21 +35,24 @@ var rootCmd = &cobra.Command{
 	Short:   "",
 	Long:    ``,
 	Version: ver.GitVersion,
-	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+	RunE: func(cmd *cobra.Command, args []string) error {
 		logger := logging.GetLogger()
 		logger.Info().Str("appVersion", ver.GitVersion).Str("goVersion", ver.GoVersion).Str("goOS", ver.GoOs).
 			Str("goArch", ver.GoArch).Str("gitCommit", ver.GitCommit).Str("buildDate", ver.BuildDate).
 			Msg("split-the-tunnel is started!")
 
-		logger.Info().Msg(opts.Domain)
-		logger.Info().Msg(opts.DnsServers)
+		// Setup signal handling for a graceful shutdown
+		sigs := make(chan os.Signal, 1)
+		signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
 
-		cmd.SetContext(context.WithValue(cmd.Context(), options.LoggerKey{}, logger))
-		cmd.SetContext(context.WithValue(cmd.Context(), options.OptsKey{}, opts))
+		// Initialize IPC mechanism
+		if err := initIPC(logger); err != nil {
+			logger.Fatal().Err(err).Msg("failed to initialize IPC")
+		}
+
+		<-sigs
+		logger.Info().Msg("received termination signal, shutting down...")
 
-		return nil
-	},
-	RunE: func(cmd *cobra.Command, args []string) error {
 		return nil
 	},
 }
@@ -53,3 +64,118 @@ func Execute() {
 		os.Exit(1)
 	}
 }
+
+const socketPath = "/tmp/mydaemon.sock"
+
+func initIPC(logger zerolog.Logger) error {
+	// Check and remove the socket file if it already exists
+	if _, err := os.Stat(socketPath); err == nil {
+		if err := os.Remove(socketPath); err != nil {
+			return err
+		}
+	}
+
+	// Listen on the UNIX domain socket
+	listener, err := net.Listen("unix", socketPath)
+	if err != nil {
+		return err
+	}
+
+	go func() {
+		defer listener.Close()
+		for {
+			// Accept new connections
+			conn, err := listener.Accept()
+			if err != nil {
+				logger.Error().Err(err).Msg("failed to accept connection")
+				continue
+			}
+
+			// Handle the connection in a new goroutine
+			go handleConnection(conn, logger)
+		}
+	}()
+
+	return nil
+}
+
+func handleConnection(conn net.Conn, logger zerolog.Logger) {
+	reader := bufio.NewReader(conn)
+	for {
+		message, err := reader.ReadString('\n')
+		if err != nil {
+			if err != io.EOF {
+				logger.Error().Err(err).Msg("failed to read from IPC connection")
+				continue
+			}
+		}
+
+		// Process the received command
+		if err := processCommand(strings.TrimSpace(message), conn); err != nil {
+			logger.Error().Err(err).Msg("failed to process command")
+			break
+		}
+	}
+}
+
+func processCommand(command string, conn net.Conn) error {
+	parts := strings.Fields(command)
+	if len(parts) == 0 {
+		return errors.New("not enough arguments")
+	}
+
+	switch parts[0] {
+	case "add":
+		if len(parts) < 2 {
+			err := errors.New("add command requires a domain name")
+			_, err = conn.Write([]byte("Error: 'add' command requires a domain name\n"))
+			return err
+		}
+		return handleAddCommand(parts[1], conn)
+	case "remove":
+		if len(parts) < 2 {
+			err := errors.New("remove command requires a domain name")
+			_, err = conn.Write([]byte("Error: 'remove' command requires a domain name\n"))
+			return err
+		}
+		return handleRemoveCommand(parts[1], conn)
+	case "list":
+		return handleListCommand(conn)
+	default:
+		_, err := conn.Write([]byte("Error: Unknown command\n"))
+		return err
+	}
+}
+
+func handleAddCommand(domain string, conn net.Conn) error {
+	// Add logic to handle adding route for domain
+	// Placeholder for adding functionality
+
+	//_, err := conn.Write([]byte("Added route for " + domain + "\n"))
+	//return err
+
+	fmt.Println("handling add command for domain: " + domain)
+	return nil
+}
+
+func handleRemoveCommand(domain string, conn net.Conn) error {
+	// Add logic to handle removing route for domain
+	// Placeholder for removing functionality
+
+	//_, err := conn.Write([]byte("Removed route for " + domain + "\n"))
+	//return err
+
+	fmt.Println("handling remove command for domain: " + domain)
+	return nil
+}
+
+func handleListCommand(conn net.Conn) error {
+	// Add logic to list all routes
+	// Placeholder for listing functionality
+
+	//_, err := conn.Write([]byte("List of all routes\n"))
+	//return err
+
+	fmt.Println("handling list command")
+	return nil
+}