Fix hc.api.views.notification_status to always return 200

If the notification does not exist, or is more than a hour
old, return HTTP 200 (instead of 400 or 404) so the other
party doesn't retry over and over again.

hc/api/tests/test_notification_status.py

@@ -67,7 +67,7 @@ class NotificationStatusTestCase(BaseTestCase):
         fake_code = "07c2f548-9850-4b27-af5d-6c9dc157ec02"
         url = f"/api/v1/notifications/{fake_code}/status"
         r = self.client.post(url, {"MessageStatus": "failed"})
-        self.assertEqual(r.status_code, 404)
+        self.assertEqual(r.status_code, 200)
 
     def test_it_requires_post(self):
         r = self.client.get(self.url)

hc/api/views.py

@@ -436,12 +436,12 @@ def badge(request, badge_key, signature, tag, fmt):
 def notification_status(request, code):
     """ Handle notification delivery status callbacks. """
 
-    notification = get_object_or_404(Notification, code=code)
-
-    td = timezone.now() - notification.created
-    if td.total_seconds() > 3600:
-        # If the webhook is called more than 1 hour after the notification, ignore it.
-        # Return HTTP 200 so the other party doesn't retry over and over again:
+    try:
+        cutoff = timezone.now() - td(hours=1)
+        notification = Notification.objects.get(code=code, created__gt=cutoff)
+    except Notification.DoesNotExist:
+        # If the notification does not exist, or is more than a hour old,
+        # return HTTP 200 so the other party doesn't retry over and over again:
         return HttpResponse()
 
     error, mark_not_verified = None, False

hc/front/views.py

@@ -477,7 +477,6 @@ def cron_preview(request):
         for i in range(0, 6):
             ctx["dates"].append(it.get_next(datetime))
 
-            pass
     except UnknownTimeZoneError:
         ctx["bad_tz"] = True
     except: