From a0529af10f367c0140cf7f0afcc09d4d6321a9de Mon Sep 17 00:00:00 2001
From: Achraf Labidi <achraf.labidi@tum.de>
Date: Sat, 3 Feb 2024 17:54:23 +0100
Subject: [PATCH] Use cached token instead of fetching

---
 .../networking/api/handler/grpc_handler.dart  |  8 +-------
 .../networking/api/handler/token_handler.dart | 20 ++++++++++++++++++-
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/lib/base/networking/api/handler/grpc_handler.dart b/lib/base/networking/api/handler/grpc_handler.dart
index 89ec8f9..13a2b75 100644
--- a/lib/base/networking/api/handler/grpc_handler.dart
+++ b/lib/base/networking/api/handler/grpc_handler.dart
@@ -9,7 +9,6 @@ import 'package:logger/logger.dart';
 /// Handles gRPC communication for the application.
 class GrpcHandler {
   static final Logger _logger = Logger();
-
   final String host;
   final int port;
   late ClientChannel _channel;
@@ -42,13 +41,8 @@ class GrpcHandler {
     Future<T> Function(APIClient client) grpcMethod,
   ) async {
     _logger.d('callGrpcMethod: Initiating gRPC call');
+    final token = await TokenHandler.getToken();
     try {
-      String token = '';
-      try {
-        token = await TokenHandler.loadToken('jwt');
-      }catch(e) {
-        token = '';
-      }
       CallOptions callOptions;
       if(token.isNotEmpty) {
         final metadata = <String, String>{
diff --git a/lib/base/networking/api/handler/token_handler.dart b/lib/base/networking/api/handler/token_handler.dart
index cf970fe..1499e45 100644
--- a/lib/base/networking/api/handler/token_handler.dart
+++ b/lib/base/networking/api/handler/token_handler.dart
@@ -11,6 +11,8 @@ import 'package:logger/logger.dart';
 class TokenHandler {
   static final Logger _logger = Logger();
   static const _storage = FlutterSecureStorage();
+  static String cachedToken = '';
+
 
   /// Stores a token.
   ///
@@ -84,7 +86,6 @@ class TokenHandler {
         _logger.w('Token not found for key: $key');
         return "";
       }
-
       _logger.i('Token successfully loaded for key: $key');
       return token;
     } catch (e) {
@@ -103,10 +104,27 @@ class TokenHandler {
   static Future<void> deleteToken(String key) async {
     try {
       await _storage.delete(key: key);
+      await _invalidateToken();
       _logger.i('Token successfully deleted for key: $key');
     } catch (e) {
       _logger.e('Error deleting token: $e');
       throw AppError.notFound();
     }
   }
+
+  static Future<String> getToken() async {
+    if(cachedToken.isNotEmpty) {
+      _logger.d('Using cached token');
+      return cachedToken;
+    }
+    _logger.d('Loading token from storage');
+    cachedToken = await loadToken('jwt');
+    return cachedToken;
+  }
+
+  static Future<void> _invalidateToken() async {
+    cachedToken = '';
+  }
+
+
 }