GODT-2013: CLI flag for frontend is required (v3)

internal/app/app.go

@@ -54,10 +54,14 @@ const (
 	flagLogLevel      = "log-level"
 	flagLogLevelShort = "l"
 
+	flagGRPC      = "grpc"
+	flagGRPCShort = "g"
+
 	flagCLI      = "cli"
 	flagCLIShort = "c"
 
-	flagNonInteractive = "non-interactive"
+	flagNonInteractive      = "noninteractive"
+	flagNonInteractiveShort = "n"
 
 	flagLogIMAP = "log-imap"
 	flagLogSMTP = "log-smtp"
@@ -95,13 +99,19 @@ func New() *cli.App {
 			Usage:   "Set the log level (one of panic, fatal, error, warn, info, debug)",
 		},
 		&cli.BoolFlag{
-			Name:    flagCLI,
+			Name:    flagGRPC,
-			Aliases: []string{flagCLIShort},
+			Aliases: []string{flagGRPCShort},
-			Usage:   "Use command line interface",
+			Usage:   "Start the gRPC service",
 		},
 		&cli.BoolFlag{
-			Name:  flagNonInteractive,
+			Name:    flagCLI,
-			Usage: "Run the app in non-interactive mode",
+			Aliases: []string{flagCLIShort},
+			Usage:   "Start the command line interface",
+		},
+		&cli.BoolFlag{
+			Name:    flagNonInteractive,
+			Aliases: []string{flagNonInteractiveShort},
+			Usage:   "Start the app in non-interactive mode",
 		},
 		&cli.StringFlag{
 			Name:  flagLogIMAP,

internal/app/frontend.go

@@ -27,6 +27,7 @@ import (
 	"github.com/ProtonMail/proton-bridge/v2/internal/frontend/grpc"
 	"github.com/ProtonMail/proton-bridge/v2/internal/locations"
 	"github.com/ProtonMail/proton-bridge/v2/pkg/restarter"
+	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 )
 
@@ -45,12 +46,19 @@ func runFrontend(
 	case c.Bool(flagNonInteractive):
 		select {}
 
-	default:
+	case c.Bool(flagGRPC):
 		service, err := grpc.NewService(crashHandler, restarter, locations, bridge, eventCh, !c.Bool(flagNoWindow))
 		if err != nil {
 			return fmt.Errorf("could not create service: %w", err)
 		}
 
 		return service.Loop()
+
+	default:
+		if err := cli.ShowAppHelp(c); err != nil {
+			logrus.WithError(err).Error("Failed to show app help")
+		}
+
+		return fmt.Errorf("no frontend specified, use --cli, --grpc or --noninteractive")
 	}
 }

internal/frontend/bridge-gui/bridge-gui/main.cpp

@@ -257,7 +257,7 @@ void launchBridge(QStringList const &args)
     else
         app().log().debug(QString("Bridge executable path: %1").arg(QDir::toNativeSeparators(bridgeExePath)));
 
-    overseer = std::make_unique<Overseer>(new ProcessMonitor(bridgeExePath, args, nullptr), nullptr);
+    overseer = std::make_unique<Overseer>(new ProcessMonitor(bridgeExePath, QStringList("--grpc") + args, nullptr), nullptr);
     overseer->startWorker(true);
 }