fortify/config: flag to print template config serialised as JSON

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>

config.go

@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/json"
 	"flag"
+	"fmt"
 	"os"
 
 	"git.ophivana.moe/cat/fortify/dbus"
@@ -12,6 +13,8 @@ import (
 )
 
 var (
+	printTemplate bool
+
 	confPath string
 
 	dbusConfigSession string
@@ -27,6 +30,8 @@ var (
 )
 
 func init() {
+	flag.BoolVar(&printTemplate, "template", false, "Print a full config template and exit")
+
 	// config file, disables every other flag here
 	flag.StringVar(&confPath, "c", "nil", "Path to full app configuration, or \"nil\" to configure from flags")
 
@@ -52,6 +57,18 @@ func init() {
 	flag.StringVar(&launchMethodText, "method", "sudo", methodHelpString)
 }
 
+func tryTemplate() {
+	if printTemplate {
+		if s, err := json.MarshalIndent(app.Template(), "", "  "); err != nil {
+			fatalf("cannot generate template: %v", err)
+			panic("unreachable")
+		} else {
+			fmt.Println(string(s))
+		}
+		os.Exit(0)
+	}
+}
+
 func loadConfig() *app.Config {
 	if confPath == "nil" {
 		// config from flags

main.go

@@ -32,9 +32,10 @@ func main() {
 		shim.Try()
 	}
 
-	// version/license command early exit
+	// version/license/template command early exit
 	tryVersion()
 	tryLicense()
+	tryTemplate()
 
 	// state query command early exit
 	tryState()