fix(utils): now it can be successfully restarted when deployed as systemd service

- Add `getSystemdServiceName` function to get systemd service name.
- When detected as systemd sevice, use `systemctl restart` to restart the program then exit.

utils/handlers.go

@@ -170,6 +170,8 @@ func IsFileExist(filePath string) bool {
 	return !os.IsNotExist(err)
 }
 
+var pendingSystemdRestart string
+
 func RestartHandler(w http.ResponseWriter, r *http.Request) {
 	userID, err := Auth(w, r, http.MethodGet, "superuser", "admin")
 	if err != nil {
@@ -185,14 +187,34 @@ func RestartHandler(w http.ResponseWriter, r *http.Request) {
 	}
 	SendSuccessResponse(w, "Restarting server...", nil)
 	postLog.Info(fmt.Sprintf("[RestartHandler] [%d] Restarting server", userID))
+
+	if pendingSystemdRestart != "" {
+		serviceName := pendingSystemdRestart
+		go func() {
+			time.Sleep(500 * time.Millisecond)
+			cmd := exec.Command("systemctl", "restart", serviceName)
+			if err := cmd.Run(); err != nil {
+				postLog.Error(fmt.Sprintf("[RestartHandler] [%d] failed to restart systemd service %s: %v", userID, serviceName, err))
+			}
+		}()
+	}
 }
 
 func RestartProcess() error {
+	if getInitSystem() == "systemd" {
+		serviceName, err := getSystemdServiceName()
+		if err != nil {
+			return fmt.Errorf("failed to get systemd service name: %w", err)
+		}
+		pendingSystemdRestart = serviceName
+		return nil
+	}
+
 	executable, err := os.Executable()
 	if err != nil {
 		return fmt.Errorf("failed to get executable path: %w", err)
 	}
-	cmd := exec.Command(executable)
+	cmd := exec.Command(executable, os.Args[1:]...)
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 	if err := cmd.Start(); err != nil {

utils/sys.go

@@ -0,0 +1,41 @@
+package utils
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"runtime"
+)
+
+func getSystemdServiceName() (string, error) {
+	data, err := os.ReadFile("/proc/self/cgroup")
+	if err == nil {
+		for _, line := range strings.Split(string(data), "\n") {
+			if !strings.Contains(line, ".service") {
+				continue
+			}
+			for _, part := range strings.Split(line, "/") {
+				part = strings.TrimSpace(part)
+				if strings.HasSuffix(part, ".service") {
+					return part, nil
+				}
+			}
+		}
+	}
+	return "", fmt.Errorf("could not determine systemd service name from cgroup")
+}
+
+func getInitSystem() string {
+	if runtime.GOOS == "windows" {
+		return "windows"
+	}
+	if runtime.GOOS == "linux" {
+		if _, err := os.Stat("/run/systemd/system"); err == nil {
+			return "systemd"
+		}
+		if _, err := os.Stat("/etc/init.d"); err == nil {
+			return "init.d"
+		}
+	}
+	return "unknown"
+}