push_notifications: Clear push notifications on message deletion.

This commit adds support to revoke mobile push notifications
for messages when deleted.

Fixes #26584.

Signed-off-by: Prakhar Pratyush <prakhar@zulip.com>

zerver/actions/message_delete.py

@@ -2,6 +2,7 @@ from collections import defaultdict
 from collections.abc import Iterable
 from typing import TypedDict
 
+from zerver.actions.message_flags import do_clear_mobile_push_notifications_for_ids
 from zerver.lib import retention
 from zerver.lib.message import event_recipient_ids_for_action_on_messages
 from zerver.lib.retention import move_messages_to_archive
@@ -105,12 +106,14 @@ def do_delete_messages(
     When the Recipient.PERSONAL is no longer a case to consider, this
     restriction can be deleted.
     """
+    message_ids = []
     private_messages_by_recipient: defaultdict[int, list[Message]] = defaultdict(list)
     stream_messages_by_recipient_and_topic: defaultdict[tuple[int, str], list[Message]] = (
         defaultdict(list)
     )
     stream_by_recipient_id = {}
     for message in messages:
+        message_ids.append(message.id)
         if message.is_channel_message:
             recipient_id = message.recipient_id
             # topics are case-insensitive.
@@ -120,6 +123,8 @@ def do_delete_messages(
             recipient_id = message.recipient.id
             private_messages_by_recipient[recipient_id].append(message)
 
+    do_clear_mobile_push_notifications_for_ids(user_profile_ids=None, message_ids=message_ids)
+
     for recipient_id, grouped_messages in sorted(private_messages_by_recipient.items()):
         _process_grouped_messages_deletion(
             realm, grouped_messages, stream=None, topic=None, acting_user=acting_user

zerver/actions/message_flags.py

@@ -220,16 +220,22 @@ def do_update_mobile_push_notification(
 
 
 def do_clear_mobile_push_notifications_for_ids(
-    user_profile_ids: list[int], message_ids: list[int]
+    user_profile_ids: list[int] | None, message_ids: list[int]
 ) -> None:
     if len(message_ids) == 0:
         return
 
-    # This function supports clearing notifications for several users
-    # only for the message-edit use case where we'll have a single message_id.
+    if user_profile_ids is not None:
+        # This block gets executed in the following cases:
+        # * Message(s) marked as read by a user
+        # * A message edited to remove mention(s)
+        if len(user_profile_ids) == 0:
+            return
+
+        # This supports clearing notifications for several users only for
+        # the message-edit use case where we'll have a single message_id.
         assert len(user_profile_ids) == 1 or len(message_ids) == 1
 
-    messages_by_user = defaultdict(list)
         notifications_to_update = (
             UserMessage.objects.filter(
                 message_id__in=message_ids,
@@ -240,7 +246,20 @@ def do_clear_mobile_push_notifications_for_ids(
             )
             .values_list("user_profile_id", "message_id")
         )
+    else:
+        # This block handles clearing notifications when message(s) get deleted.
+        notifications_to_update = (
+            # Uses index: zerver_usermessage_message_active_mobile_push_notification_idx
+            UserMessage.objects.filter(
+                message_id__in=message_ids,
+            )
+            .extra(  # noqa: S610
+                where=[UserMessage.where_active_push_notification()],
+            )
+            .values_list("user_profile_id", "message_id")
+        )
 
+    messages_by_user = defaultdict(list)
     for user_id, message_id in notifications_to_update:
         messages_by_user[user_id].append(message_id)
 

zerver/migrations/0755_usermessage_zerver_usermessage_message_active_mobile_push_notification_idx.py

@@ -0,0 +1,23 @@
+# Generated by Django 5.2.7 on 2025-10-29 05:28
+
+from django.contrib.postgres.operations import AddIndexConcurrently
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    atomic = False
+    dependencies = [
+        ("zerver", "0754_merge_20251014_1855"),
+    ]
+
+    operations = [
+        AddIndexConcurrently(
+            model_name="usermessage",
+            index=models.Index(
+                models.F("message"),
+                condition=models.Q(("flags__andnz", 4096)),
+                name="zerver_usermessage_message_active_mobile_push_notification_idx",
+            ),
+        ),
+        migrations.RunSQL("ANALYZE zerver_usermessage"),
+    ]

zerver/models/messages.py

@@ -642,6 +642,13 @@ class UserMessage(AbstractUserMessage):
                 ),
                 name="zerver_usermessage_active_mobile_push_notification_id",
             ),
+            models.Index(
+                "message",
+                condition=Q(
+                    flags__andnz=AbstractUserMessage.flags.active_mobile_push_notification.mask
+                ),
+                name="zerver_usermessage_message_active_mobile_push_notification_idx",
+            ),
         ]
 
     @override

zerver/tests/test_message_delete.py

@@ -10,8 +10,9 @@ from zerver.actions.message_delete import do_delete_messages
 from zerver.actions.realm_settings import do_change_realm_permission_group_setting
 from zerver.actions.streams import do_change_stream_group_based_setting, do_deactivate_stream
 from zerver.actions.user_groups import check_add_user_group
+from zerver.actions.user_settings import do_change_user_setting
 from zerver.lib.test_classes import ZulipTestCase
-from zerver.models import Message, NamedUserGroup, UserProfile
+from zerver.models import Message, NamedUserGroup, UserMessage, UserProfile
 from zerver.models.groups import SystemGroups
 from zerver.models.realms import get_realm
 from zerver.models.streams import get_stream
@@ -914,7 +915,62 @@ class DeleteMessageTest(ZulipTestCase):
         self.assertEqual(stream.first_message_id, message_ids[1])
 
         all_messages = Message.objects.filter(id__in=message_ids)
-        with self.assert_database_query_count(25):
+        with self.assert_database_query_count(26):
             do_delete_messages(realm, all_messages, acting_user=None)
         stream = get_stream(stream_name, realm)
         self.assertEqual(stream.first_message_id, None)
+
+    @mock.patch("zerver.lib.push_notifications.send_push_notifications")
+    @mock.patch("zerver.lib.push_notifications.push_notifications_configured", return_value=True)
+    def test_clear_push_notifications_on_message_deletion(
+        self,
+        mock_push_notifications: mock.MagicMock,
+        mock_send_push_notifications: mock.MagicMock,
+    ) -> None:
+        realm = get_realm("zulip")
+        hamlet = self.example_user("hamlet")
+        cordelia = self.example_user("cordelia")
+        self.register_push_device(cordelia.id)
+        do_change_user_setting(cordelia, "enable_stream_push_notifications", True, acting_user=None)
+
+        def get_message_ids_with_active_push_notification(user_profile: UserProfile) -> list[int]:
+            return list(
+                UserMessage.objects.filter(
+                    user_profile=user_profile,
+                )
+                .extra(  # noqa: S610
+                    where=[UserMessage.where_active_push_notification()],
+                )
+                .order_by("message_id")
+                .values_list("message_id", flat=True)
+            )
+
+        # Initially, no active push notifications.
+        self.assertEqual(get_message_ids_with_active_push_notification(cordelia), [])
+
+        self.subscribe(cordelia, "Verona")
+        message_ids = [self.send_stream_message(hamlet, "Verona")]
+
+        # Verify push notifications sent to `cordelia` for `message_ids`
+        self.assertEqual(
+            get_message_ids_with_active_push_notification(cordelia),
+            message_ids,
+        )
+
+        messages = Message.objects.filter(id__in=message_ids)
+        with (
+            mock.patch(
+                "zerver.worker.missedmessage_mobile_notifications.handle_remove_push_notification"
+            ) as mock_handle_remove_push_notification,
+            self.captureOnCommitCallbacks(execute=True),
+        ):
+            do_delete_messages(realm, messages, acting_user=None)
+
+        # Verify messages deleted, `handle_remove_push_notification` called
+        # to clear/revoke push notifications, usermessages deleted.
+        self.assertFalse(Message.objects.filter(id__in=message_ids).exists())
+        mock_handle_remove_push_notification.assert_called_once()
+        self.assertEqual(
+            get_message_ids_with_active_push_notification(cordelia),
+            [],
+        )

zerver/tests/test_retention.py

@@ -1151,7 +1151,7 @@ class TestDoDeleteMessages(ZulipTestCase):
         message_ids = [self.send_stream_message(cordelia, "Verona", str(i)) for i in range(10)]
         messages = Message.objects.filter(id__in=message_ids)
 
-        with self.assert_database_query_count(23):
+        with self.assert_database_query_count(24):
             do_delete_messages(realm, messages, acting_user=None)
         self.assertFalse(Message.objects.filter(id__in=message_ids).exists())