[Hotfix] Evite les notifications persistantes à la suppression d'un MP.

update.md

@@ -569,6 +569,14 @@ Il faudra supprimer en SQL:
 
 S'il y a une erreur pour `article_article_subcategory` et `DROP TABLE tutorial_tutorial_subcategory;` c'est que les tables ont déjà été supprimées précédement (ZEP-25).
 
+Actions à faire pour mettre en prod la version 18.2
+===================================================
+
+Notifications
+-------------
+
+Lancez la commande `python manage.py delete_useless_notif` pour supprimer toutes les notifications inutiles.
+
 ---
 
 **Notes auxquelles penser lors de l'édition de ce fichier (à laisser en bas) :**

zds/notification/management/commands/delete_useless_notif.py

@@ -0,0 +1,21 @@
+# coding: utf-8
+from django.contrib.contenttypes.models import ContentType
+from django.core.management import BaseCommand
+
+from zds.member.models import Profile
+from zds.notification.models import Notification
+
+
+class Command(BaseCommand):
+    help = 'Remove useless notifications for private topics.'
+
+    def handle(self, *args, **options):
+        for profile in Profile.objects.all():
+            self.stdout.write(u'Remove all useless notifications of {}...'.format(profile.user.username))
+            content_type = ContentType.objects.get(model='privatepost')
+            for notification in Notification.objects\
+                    .filter(is_read=False, content_type=content_type, subscription__user=profile.user):
+                if notification.content_object is None:
+                    notification.is_read = True
+                    notification.save()
+                    self.stdout.write(u'Notification #{} marked as read.'.format(notification.id))

zds/notification/receivers.py

@@ -232,6 +232,17 @@ def add_participant_topic_event(sender, **kwargs):
                     subscription.deactivate()
 
 
+@receiver(pre_delete, sender=PrivateTopic)
+def delete_private_topic_event(sender, instance, **kwargs):
+    """
+    A private topic is deleted when there is nobody in this private topic.
+    """
+    subscriptions = PrivateTopicAnswerSubscription.objects.get_subscriptions(content_object=instance, is_active=True)
+    for subscription in subscriptions:
+        subscription.mark_notification_read()
+        subscription.deactivate()
+
+
 @receiver(pre_delete, sender=User)
 def delete_notifications(sender, instance, **kwargs):
     """

zds/notification/tests.py

@@ -451,17 +451,20 @@ def test_remove_notifications_when_a_user_leave_private_topic(self):
         self.assertIsNotNone(notifications.first())
         self.assertEqual(topic.last_message, notifications.first().content_object)
 
-        self.assertIsNotNone(
-            PrivateTopicAnswerSubscription.objects.get_existing(self.user2, topic, is_active=True))
+        self.assertIsNotNone(PrivateTopicAnswerSubscription.objects.get_existing(self.user2, topic, is_active=True))
 
+        send_message_mp(self.user2, topic, "Test")
         topic.participants.remove(self.user2)
         topic.save()
 
-        notifications = Notification.objects.get_unread_notifications_of(self.user2)
-        self.assertEqual(0, len(notifications))
+        self.assertEqual(0, len(Notification.objects.get_unread_notifications_of(self.user2)))
+        self.assertIsNotNone(PrivateTopicAnswerSubscription.objects.get_existing(self.user2, topic, is_active=False))
+
+        self.assertEqual(1, len(Notification.objects.get_unread_notifications_of(self.user1)))
 
-        self.assertIsNotNone(
-            PrivateTopicAnswerSubscription.objects.get_existing(self.user2, topic, is_active=False))
+        response = self.client.post(reverse('mp-delete', args=[topic.pk, topic.slug]), follow=True)
+        self.assertEqual(200, response.status_code)
+        self.assertEqual(0, len(Notification.objects.get_unread_notifications_of(self.user1)))
 
     def test_send_an_email_when_we_specify_it(self):
         """