frontend: add a timestamp file for time checking on backend

frontend/main.go

@@ -11,6 +11,7 @@ import (
 	"path"
 	"strings"
 	"syscall"
+	"time"
 
 	"srs.epita.fr/fic-server/settings"
 )
@@ -95,8 +96,21 @@ func main() {
 	}()
 	log.Println(fmt.Sprintf("Ready, listening on %s", *bind))
 
-	// Wait shutdown signal
+	// Wait shutdown signal and touch timestamp
-	<-interrupt
+	ticker := time.NewTicker(time.Second)
+	defer ticker.Stop()
+
+loop:
+	for {
+		select {
+		case <-interrupt:
+			break loop
+		case <-ticker.C:
+			now := time.Now()
+			os.Chtimes(SubmissionDir, now, now)
+		}
+	}
+
 
 	log.Print("The service is shutting down...")
 	srv.Shutdown(context.Background())