Implement global debug support for client

cmd/syringe/update_linux.go

@@ -30,6 +30,17 @@ func updateEntrypoint(clictx *cli.Context) (err error) {
 	runtime.GOMAXPROCS(1)
 	ctx := clictx.Context
 
+	// Reconfigure logger according to debug value via dbus service
+	// We need dbus service to be available in update mode anyway
+	if debug, derr := dbus.GetGlobalDebug(ctx); derr != nil {
+		zap.L().Debug("unable to get global debug flag", zap.Error(err))
+	} if debug && !(clictx.Bool("debug") || clictx.Bool("global-debug")) {
+		if err = setupLogging(true); err != nil {
+			return
+		}
+		zap.L().Debug("global debugging enabled")
+	}
+
 	if os.Getuid() != 0 && os.Geteuid() != 0 {
 		zap.L().Error("effective uid is not 0, very likely unable to update credentials", zap.Int("uid", os.Getuid()), zap.Int("euid", os.Geteuid()))
 	}

internal/dbus/syringe.go

@@ -33,3 +33,24 @@ func GetServiceSocketPaths(ctx context.Context) (socketPaths map[string]bool, er
 
 	return
 }
+
+func GetGlobalDebug(ctx context.Context) (debug bool, err error) {
+	var conn *dbus.Conn
+
+	if conn, err = dbus.ConnectSystemBus(); err != nil {
+		err = fmt.Errorf("failed to establish dbus connection: %w", err)
+		return
+	}
+	defer conn.Close()
+
+	var globalDebugValue dbus.Variant
+	obj := conn.Object(intf, objPath)
+	err = obj.CallWithContext(ctx, "ee.zentria.syringe1.Syringe.GetGlobalDebug", 0).Store(&globalDebugValue)
+	if err != nil {
+		err = fmt.Errorf("failed to call GetGlobalDebug: %w", err)
+		return
+	}
+
+	debug = globalDebugValue.Value().(bool)
+	return
+}