Fix Django Debug Toolbar redirect loop in Quizzes

api/urls.py

@@ -12,7 +12,7 @@
     path("task-list/<subject_abbr>", default_view.tasks_list_all),
     path("student-list", default_view.student_list),
     path("submits/<int:task_assignment>", default_view.create_submit),
-    path("info", default_view.info),
+    path("info", default_view.info, name="api_info"),
     path("classes", default_view.class_detail_list),
     path("classes/all", default_view.all_classes),
     path("classes/<int:class_id>/add_students", default_view.add_student_to_class),

quiz/middleware.py

@@ -1,7 +1,9 @@
 from django.http import HttpResponseRedirect
 from django.urls import reverse, resolve, Resolver404
 from enum import Enum
-from quiz.models import EnrolledQuiz
+from kelvin.settings import DEBUG
+from debug_toolbar.toolbar import DebugToolbar
+from quiz.quiz_utils import quiz_running_for_user
 
 
 class SubmitType(Enum):
@@ -19,15 +21,16 @@ def __init__(self, get_response):
         self.get_response = get_response
 
     def __call__(self, request):
-        try:
-            enrolled_quiz = EnrolledQuiz.objects.get(student=request.user.id, submitted=False)
+        enrolled_quiz = quiz_running_for_user(request.user)
 
+        if enrolled_quiz is not None:
             fill_url = reverse("quiz_fill")
 
             allowed_urls = [
                 fill_url,
                 reverse("api_quiz_results", args=[enrolled_quiz.id, SubmitType.PERIODIC.value]),
                 reverse("api_quiz_results", args=[enrolled_quiz.id, SubmitType.MANUAL.value]),
+                reverse("api_info"),
                 reverse("cas_ng_logout"),
             ]
 
@@ -37,10 +40,9 @@ def __call__(self, request):
             except Resolver404:
                 pass
 
-            if request.path_info not in allowed_urls:
+            debug_toolbar = DEBUG and DebugToolbar.is_toolbar_request(request)
+            if not debug_toolbar and request.path_info not in allowed_urls:
                 return HttpResponseRedirect(fill_url)
-        except EnrolledQuiz.DoesNotExist:
-            pass
 
         response = self.get_response(request)
 

quiz/quiz_utils.py

@@ -1,5 +1,6 @@
 from django.contrib.auth.models import User
 
+from typing import Optional
 from common.models import Class
 from quiz.models import Quiz, AssignedQuiz, EnrolledQuiz
 from web.markdown_utils import process_markdown
@@ -13,6 +14,20 @@ class QuizException(Exception):
     pass
 
 
+def quiz_running_for_user(user: User) -> Optional[EnrolledQuiz]:
+    """
+    Returns currently running quiz for given user.
+    If user is not running a quiz at the moment, None is returned.
+    """
+    try:
+        return EnrolledQuiz.objects.get(student=user.id, submitted=False)
+    except EnrolledQuiz.DoesNotExist:
+        return None
+
+
+User.add_to_class("is_running_quiz", lambda self: quiz_running_for_user(self) is not None)
+
+
 def quiz_assigned_classes(quiz: Quiz, requested_by: int):
     """
     Function that returns a list of classes that are/can be assigned to the quiz.

templates/web/layout.html

@@ -68,7 +68,9 @@
                 <span class="ml-auto navbar-text">
                   <span class="d-md-none">Logged as: </span><span class="text-body-emphasis">{{ user.get_full_name }} ({{ user.username }})</span>
                 </span>
+                {% if not user.is_running_quiz %}
                 <kelvin-notifications></kelvin-notifications>
+                {% endif %}
 
                 <kelvin-color-theme></kelvin-color-theme>
                 <li class="nav-item"><a class="nav-link text-primary-emphasis" href="/accounts/logout/?next=/">Logout</a></li>