Improve error handling for settings. Instead of failing with an exception, an alert is displayed on the main page when something isn't set properly.

app/YtManagerApp/scheduler.py

@@ -1,19 +1,19 @@
 import logging
 import sys
 from apscheduler.schedulers.background import BackgroundScheduler
+from django.conf import settings
 
 scheduler: BackgroundScheduler = None
 
 
 def initialize_scheduler():
-    from .appconfig import settings
     global scheduler
 
     logger = logging.getLogger('scheduler')
     executors = {
         'default': {
             'type': 'threadpool',
-            'max_workers': settings.getint('global', 'SchedulerConcurrency')
+            'max_workers': settings.SCHEDULER_CONCURRENCY
         }
     }
     job_defaults = {

app/YtManagerApp/templates/YtManagerApp/index.html

@@ -24,6 +24,8 @@
         </div>
     </div>
 
+    {% include 'YtManagerApp/index_errors_banner.html' %}
+
     <div class="row">
 
         <div class="col-3">

app/YtManagerApp/templates/YtManagerApp/index_errors_banner.html

@@ -0,0 +1,24 @@
+{% if config_errors %}
+    <div class="alert alert-danger alert-card mx-auto">
+        <p>Attention! Some critical configuration errors have been found!</p>
+        <ul>
+            {% for err in config_errors %}
+                <li>{{ err }}</li>
+            {% endfor %}
+        </ul>
+        <p>Until these problems are fixed, the server may have encounter serious problems while running.
+            Please correct these errors, and then restart the server.</p>
+    </div>
+{% endif %}
+
+{% if config_warnings %}
+    <div class="alert alert-warning alert-card mx-auto">
+        <p>Warning: some configuration problems have been found!</p>
+        <ul>
+            {% for err in config_warnings %}
+                <li>{{ err }}</li>
+            {% endfor %}
+        </ul>
+        <p>We recommend that you fix these issues before continuing.</p>
+    </div>
+{% endif %}

app/YtManagerApp/templates/YtManagerApp/index_unauthenticated.html

@@ -3,6 +3,8 @@
 
 {% block body %}
 
+    {% include 'YtManagerApp/index_errors_banner.html' %}
+
     <h1>Hello</h1>
     <h2>Please log in to continue</h2>
 

app/YtManagerApp/views/index.py

@@ -8,7 +8,7 @@ from django.http import HttpRequest, HttpResponseBadRequest, JsonResponse
 from django.shortcuts import render
 from django.views.generic import CreateView, UpdateView, DeleteView, FormView
 from django.views.generic.edit import FormMixin
-
+from django.conf import settings
 from YtManagerApp.management.videos import get_videos
 from YtManagerApp.models import Subscription, SubscriptionFolder, VIDEO_ORDER_CHOICES, VIDEO_ORDER_MAPPING
 from YtManagerApp.utils import youtube, subscription_file_parser
@@ -94,13 +94,17 @@ def __tree_sub_id(sub_id):
 
 
 def index(request: HttpRequest):
+    context = {
+        'config_errors': settings.CONFIG_ERRORS,
+        'config_warnings': settings.CONFIG_WARNINGS,
+    }
     if request.user.is_authenticated:
-        context = {
-            'filter_form': VideoFilterForm()
-        }
+        context.update({
+            'filter_form': VideoFilterForm(),
+        })
         return render(request, 'YtManagerApp/index.html', context)
     else:
-        return render(request, 'YtManagerApp/index_unauthenticated.html')
+        return render(request, 'YtManagerApp/index_unauthenticated.html', context)
 
 
 @login_required