the send_friend_request method uses Q objects to ensure that there is…

… no existing pending friend request between the two users. If a pending request exists and it was sent by the current user, it cancels the request by deleting it. If the request was sent by the other user, it informs the current user that there is already a pending request from the other user. This way, the system handles both sending and canceling friend requests efficiently.I still need to work on cancel_friend_request function

Backend/user_service/user_service/user_app/views.py

@@ -15,6 +15,7 @@
 from .models import User, FriendRequest
 from .rabbitmq_utils import consume_message, publish_message
 from .serializers import UserSerializer, FriendSerializer
+from django.db.models import Q
 
 
 class UserViewSet(viewsets.ViewSet):
@@ -270,21 +271,36 @@ def send_friend_request(self, request, user_pk=None, pk=None):
         try:
             if (user_pk == pk):
                 raise ValidationError(detail={"You can't send a friend request to yourself"}, code=status.HTTP_400_BAD_REQUEST)
-            current_user = get_object_or_404(User, id=user_pk) # current user is sending a request to the target
-            receiver = get_object_or_404(User, id=pk) # target user is the receiver of the request
-            # This FriendRequest.objects.get_or_create() function will get the object or create it
-            friend_request, created = FriendRequest.objects.get_or_create(
-                sender_user = current_user,
-                receiver_user = receiver,
-                status = 'pending'
+            current_user = get_object_or_404(User, id=user_pk)
+            receiver = get_object_or_404(User, id=pk)
+            existing_request = FriendRequest.objects.filter(
+            (Q(sender_user=current_user) & Q(receiver_user=receiver) & Q(status='pending')) |
+            (Q(sender_user=receiver) & Q(receiver_user=current_user) & Q(status='pending'))
+            ).first()
+            if existing_request:
+                if existing_request.sender_user == current_user:
+                    existing_request.delete()
+                    return Response({"detail:" "Friend request canceled"}, status=status.HTTP_200_OK)
+                else:
+                    return Response({"detail": "You have a pending friend from this user."}, status=status.HTTP_400_BAD_REQUEST)
+
+            # friend_request, created = FriendRequest.objects.get_or_create(
+            #     sender_user = current_user,
+            #     receiver_user = receiver,
+            #     status = 'pending'
+            # )
+            friend_request = FriendRequest.objects.create(
+                sender_user=current_user,
+                receiver_user=receiver,
+                status='pending'
             )
-            if created:
-                friend_request.save()
-                return Response({"detail": "Requested"}, status=status.HTTP_202_ACCEPTED)
-            return Response({"detail": f"Your request status is {friend_request.status}"}, status=status.HTTP_202_ACCEPTED)
+            # if created:
+            #     friend_request.save()
+            return Response({"detail": "Friend request sent"}, status=status.HTTP_202_ACCEPTED)
         except User.DoesNotExist:
             return Response({"detail": "Invalid user_id"}, status=status.HTTP_400_BAD_REQUEST)
-
+        except Exception as e:
+            return Response({"error": str(e)}, status=status.HTTP_400_BAD_REQUEST)
     def accept_friend_request(self, request, user_pk=None, pk=None):
         try:
             current_user = get_object_or_404(User, id=user_pk)