refactor: Update vacation retrieval and validation

- Simplify queryset logic for vacation retrieval
- Add default values for request_type and status parameters
- Implement validation for user_id and request_type in GET method
- Improve user existence check before processing requests

Author: Mahmoud-Emad

server/cshr/views/vacations.py

@@ -148,40 +148,17 @@ class VacationUserApiView(ListAPIView):
     permission_classes = [UserIsAuthenticated]
     pagination_class = BaseGeneralUserPagination
 
-    def get_queryset(self) -> Response:
+    def get_queryset(self):
         """method to get all vacations for certain user"""
         user_id = self.request.query_params.get("user_id")
-        if not user_id:
-            return CustomResponse.bad_request(message="user_id is required")
-
         year = self.request.query_params.get("year")
         if not year:
             year = datetime.now().year
 
-        request_type = self.request.query_params.get("type")
-        if not request_type:
-            request_type = "all"
+        request_type = self.request.query_params.get("type", "all")
+        status = self.request.query_params.get("status", "all")
 
-        if request_type != "all":
-            request_type = normalize_request_type(request_type)
-            if request_type is None:
-                return CustomResponse.bad_request(message="Invalid request type")
-
-        current_user: User = get_user_by_id(user_id)
-        if current_user is None:
-            return CustomResponse.not_found(
-                message="user is not found", status_code=404
-            )
-
-        queryset = None
-
-        status = self.request.query_params.get("status")
-        if not status:
-            status = "all"
-
-        queryset = filter_vacations_by_user_id(current_user.id).filter(
-            from_date__year=year
-        )
+        queryset = filter_vacations_by_user_id(user_id).filter(from_date__year=year)
 
         if request_type != "all":
             request_type = normalize_request_type(request_type)
@@ -193,6 +170,22 @@ def get_queryset(self) -> Response:
 
         return queryset.order_by("-created_at")
 
+    def get(self, request: Request, *args, **kwargs) -> Response:
+        user_id = request.query_params.get("user_id")
+        if not user_id:
+            return CustomResponse.bad_request(message="user_id is required")
+
+        request_type = request.query_params.get("type", "all")
+        if request_type != "all":
+            if normalize_request_type(request_type) is None:
+                return CustomResponse.bad_request(message="Invalid request type")
+
+        current_user = get_user_by_id(user_id)
+        if current_user is None:
+            return CustomResponse.not_found(message="user is not found")
+
+        return super().get(request, *args, **kwargs)
+
 
 class VacationsUpdateApiView(ListAPIView, GenericAPIView):
     serializer_class = VacationsUpdateSerializer