sytemd magics

README.md

@@ -94,6 +94,7 @@ Notes:
 - Status is read via `systemctl --user show <service>`.
 - Logs are read via `journalctl --user -u <service>`.
 - Both commands are executed as the workspace Unix user via `sudo -n -u <unix_user> ...`.
+- The app also auto-runs `loginctl enable-linger <unix_user>` (via sudo) to keep user systemd available without active login.
 
 ## Systemd
 

internal/app/deploy_service.go

@@ -89,5 +89,5 @@ func (a *App) deployProjectFromMain(_ context.Context, p Project) error {
 			return err
 		}
 	}
-	return runCmd("sudo", "-n", "-u", p.UnixUser, "systemctl", "--user", "restart", p.ServiceName)
+	return runSystemctlUser(p.UnixUser, "restart", p.ServiceName)
 }

internal/app/systemd_service.go

@@ -81,8 +81,8 @@ WantedBy=default.target
 	if err := os.WriteFile(servicePath, []byte(unit), 0o644); err != nil {
 		return err
 	}
-	_ = runCmd("sudo", "-n", "-u", p.UnixUser, "systemctl", "--user", "daemon-reload")
+	_ = runSystemctlUser(p.UnixUser, "daemon-reload")
-	_ = runCmd("sudo", "-n", "-u", p.UnixUser, "systemctl", "--user", "enable", "--now", p.ServiceName)
+	_ = runSystemctlUser(p.UnixUser, "enable", "--now", p.ServiceName)
 	return nil
 }
 
@@ -97,6 +97,59 @@ func homeForUnixUser(username string) (string, error) {
 	return u.HomeDir, nil
 }
 
+func userRuntimeEnv(username string) (string, string, error) {
+	u, err := user.Lookup(username)
+	if err != nil {
+		return "", "", fmt.Errorf("lookup unix user %q failed: %w", username, err)
+	}
+	runtimeDir := filepath.Join("/run/user", u.Uid)
+	busAddr := "unix:path=" + filepath.Join(runtimeDir, "bus")
+	return runtimeDir, busAddr, nil
+}
+
+func runSystemctlUser(username string, args ...string) error {
+	if err := ensureLingerEnabled(username); err != nil {
+		return err
+	}
+	runtimeDir, busAddr, err := userRuntimeEnv(username)
+	if err != nil {
+		return err
+	}
+	cmdArgs := []string{
+		"-n", "-u", username,
+		"env",
+		"XDG_RUNTIME_DIR=" + runtimeDir,
+		"DBUS_SESSION_BUS_ADDRESS=" + busAddr,
+		"systemctl", "--user",
+	}
+	cmdArgs = append(cmdArgs, args...)
+	return runCmd("sudo", cmdArgs...)
+}
+
+func runJournalctlUser(username string, args ...string) (string, error) {
+	if err := ensureLingerEnabled(username); err != nil {
+		return "", err
+	}
+	runtimeDir, busAddr, err := userRuntimeEnv(username)
+	if err != nil {
+		return "", err
+	}
+	cmdArgs := []string{
+		"-n", "-u", username,
+		"env",
+		"XDG_RUNTIME_DIR=" + runtimeDir,
+		"DBUS_SESSION_BUS_ADDRESS=" + busAddr,
+		"journalctl", "--user",
+	}
+	cmdArgs = append(cmdArgs, args...)
+	return runCmdOut("sudo", cmdArgs...)
+}
+
+func ensureLingerEnabled(username string) error {
+	// Idempotent; safe to call repeatedly.
+	return runCmd("sudo", "loginctl", "enable-linger", username)
+}
+
 type ServiceStatus struct {
 	Unit         string `json:"unit"`
 	ActiveState  string `json:"active_state"`
@@ -108,11 +161,20 @@ type ServiceStatus struct {
 }
 
 func (a *App) getServiceStatus(p Project) (ServiceStatus, error) {
-	out, err := runCmdOut(
+	out, err := func() (string, error) {
+		runtimeDir, busAddr, err := userRuntimeEnv(p.UnixUser)
+		if err != nil {
+			return "", err
+		}
+		return runCmdOut(
 			"sudo", "-n", "-u", p.UnixUser,
+			"env",
+			"XDG_RUNTIME_DIR="+runtimeDir,
+			"DBUS_SESSION_BUS_ADDRESS="+busAddr,
 			"systemctl", "--user", "show", p.ServiceName, "--no-pager",
 			"--property=ActiveState,SubState,MainPID,ExecMainStatus,Result,FragmentPath",
 		)
+	}()
 	if err != nil {
 		return ServiceStatus{}, err
 	}
@@ -142,8 +204,5 @@ func (a *App) getServiceStatus(p Project) (ServiceStatus, error) {
 }
 
 func (a *App) getServiceLogs(p Project, lines int) (string, error) {
-	return runCmdOut(
+	return runJournalctlUser(p.UnixUser, "-u", p.ServiceName, "--no-pager", "-n", strconv.Itoa(lines), "-o", "short-iso")
-		"sudo", "-n", "-u", p.UnixUser,
-		"journalctl", "--user", "-u", p.ServiceName, "--no-pager", "-n", strconv.Itoa(lines), "-o", "short-iso",
-	)
 }