zerver: Add feature for notification at rename of a stream.

Feature of sending notification to the stream using notification bot
is added. user_profile is also passed to do_rename_stream for using
the name of user who renamed the stream in notification.
Notification is sent to the stream using
internal_send_stream_message in do_rename_stream.

Fixes #11034.

zerver/lib/actions.py

@@ -3256,7 +3256,10 @@ def do_change_stream_announcement_only(stream: Stream, is_announcement_only: boo
     stream.is_announcement_only = is_announcement_only
     stream.save(update_fields=['is_announcement_only'])
 
-def do_rename_stream(stream: Stream, new_name: str, log: bool=True) -> Dict[str, str]:
+def do_rename_stream(stream: Stream,
+                     new_name: str,
+                     user_profile: UserProfile,
+                     log: bool=True) -> Dict[str, str]:
     old_name = stream.name
     stream.name = new_name
     stream.save(update_fields=["name"])
@@ -3307,7 +3310,14 @@ def do_rename_stream(stream: Stream, new_name: str, log: bool=True) -> Dict[str,
             name=old_name,
         )
         send_event(stream.realm, event, can_access_stream_user_ids(stream))
-
+    sender = get_system_bot(settings.NOTIFICATION_BOT)
+    internal_send_stream_message(
+        stream.realm,
+        sender,
+        new_name,
+        "welcome",
+        "@**%s** renamed stream **%s** to **%s**" % (user_profile.full_name, old_name, new_name)
+    )
     # Even though the token doesn't change, the web client needs to update the
     # email forwarding address to display the correctly-escaped new name.
     return {"email_address": new_email}

zerver/management/commands/rename_stream.py

@@ -24,4 +24,4 @@ class Command(ZulipBaseCommand):
         new_name = options['new_name']
 
         stream = get_stream(old_name, realm)
-        do_rename_stream(stream, new_name)
+        do_rename_stream(stream, new_name, self.user_profile)

zerver/tests/test_events.py

@@ -2094,10 +2094,9 @@ class EventsRegisterTest(ZulipTestCase):
         stream = self.make_stream('old_name')
         new_name = u'stream with a brand new name'
         self.subscribe(self.user_profile, stream.name)
-
+        notification = '<p><span class="user-mention" data-user-id="4">@King Hamlet</span> renamed stream <strong>old_name</strong> to <strong>stream with a brand new name</strong></p>'
-        action = lambda: do_rename_stream(stream, new_name)
+        action = lambda: do_rename_stream(stream, new_name, self.user_profile)
-        events = self.do_test(action, num_events=2)
+        events = self.do_test(action, num_events=3)
-
         schema_checker = self.check_events_dict([
             ('type', equals('stream')),
             ('op', equals('update')),
@@ -2118,6 +2117,39 @@ class EventsRegisterTest(ZulipTestCase):
         ])
         error = schema_checker('events[1]', events[1])
         self.assert_on_error(error)
+        schema_checker = check_dict([
+            ('stream_email_notify', equals(False)),
+            ('flags', check_list(check_string)),
+            ('email_notified', equals(True)),
+            ('type', equals('message')),
+            ('message', check_dict([
+                ('timestamp', check_int),
+                ('content', equals(notification)),
+                ('content_type', equals('text/html')),
+                ('sender_email', equals('notification-bot@zulip.com')),
+                ('sender_id', check_int),
+                ('sender_short_name', equals('notification-bot')),
+                ('display_recipient', equals(new_name)),
+                ('id', check_int),
+                ('stream_id', check_int),
+                ('sender_realm_str', check_string),
+                ('sender_full_name', equals('Notification Bot')),
+                ('is_me_message', equals(False)),
+                ('type', equals('stream')),
+                ('submessages', check_list(check_string)),
+                (TOPIC_LINKS, check_list(check_url)),
+                ('avatar_url', check_url),
+                ('reactions', check_list(None)),
+                ('client', equals('Internal')),
+                (TOPIC_NAME, equals('welcome')),
+                ('recipient_id', check_int)
+            ])),
+            ('id', check_int),
+            ('push_notified', equals(True)),
+            ('stream_push_notify', equals(False)),
+        ])
+        error = schema_checker('events[2]', events[2])
+        self.assert_on_error(error)
 
     def test_deactivate_stream_neversubscribed(self) -> None:
         stream = self.make_stream('old_name')

zerver/tests/test_subs.py

@@ -64,6 +64,7 @@ from zerver.lib.actions import (
     do_remove_default_stream_group,
     do_change_default_stream_group_description,
     do_change_default_stream_group_name,
+    do_rename_stream,
     lookup_default_stream_groups,
     can_access_stream_user_ids,
     validate_user_access_to_subscribers_helper,
@@ -464,14 +465,22 @@ class StreamAdminTest(ZulipTestCase):
             result = self.client_patch('/json/streams/%d' % (stream_id,),
                                        {'new_name': ujson.dumps('whatever')})
         self.assert_json_success(result)
-        # Should be a name event and an email address event
+        # Should be a name event, an email address event and a notification event
-        self.assert_length(events, 2)
+        self.assert_length(events, 3)
 
-        notified_user_ids = set(events[-1]['users'])
+        notified_user_ids = set(events[0]['users'])
         self.assertIn(user_profile.id, notified_user_ids)
         self.assertIn(cordelia.id, notified_user_ids)
         self.assertNotIn(prospero.id, notified_user_ids)
 
+        notified_with_bot_users = events[-1]['users']
+        notified_with_bot_user_ids = []
+        notified_with_bot_user_ids.append(notified_with_bot_users[0]['id'])
+        notified_with_bot_user_ids.append(notified_with_bot_users[1]['id'])
+        self.assertIn(user_profile.id, notified_with_bot_user_ids)
+        self.assertIn(cordelia.id, notified_with_bot_user_ids)
+        self.assertNotIn(prospero.id, notified_with_bot_user_ids)
+
     def test_rename_stream(self) -> None:
         user_profile = self.example_user('hamlet')
         email = user_profile.email
@@ -501,7 +510,6 @@ class StreamAdminTest(ZulipTestCase):
             result = self.client_patch('/json/streams/%d' % (stream_id,),
                                        {'new_name': ujson.dumps('stream_name2')})
         self.assert_json_success(result)
-
         event = events[1]['event']
         self.assertEqual(event, dict(
             op='update',
@@ -599,6 +607,27 @@ class StreamAdminTest(ZulipTestCase):
                                    {'new_name': ujson.dumps('stream_name2')})
         self.assert_json_error(result, 'Must be an organization administrator')
 
+    def test_notify_on_stream_rename(self) -> None:
+        user_profile = self.example_user('hamlet')
+        self.login(user_profile.email)
+        self.make_stream('stream_name1')
+
+        stream = self.subscribe(user_profile, 'stream_name1')
+        do_change_is_admin(user_profile, True)
+        result = self.client_patch('/json/streams/%d' % (stream.id,),
+                                   {'new_name': ujson.dumps('stream_name2')})
+        self.assert_json_success(result)
+
+        # Inspect the notification message sent
+        message = self.get_last_message()
+        actual_stream = Stream.objects.get(id=message.recipient.type_id)
+        message_content = '@**King Hamlet** renamed stream **stream_name1** to **stream_name2**'
+        self.assertEqual(message.sender.realm, user_profile.realm)
+        self.assertEqual(actual_stream.name, 'stream_name2')
+        self.assertEqual(message.recipient.type, Recipient.STREAM)
+        self.assertEqual(message.content, message_content)
+        self.assertEqual(message.sender.email, 'notification-bot@zulip.com')
+
     def test_realm_admin_can_update_unsub_private_stream(self) -> None:
         iago = self.example_user('iago')
         self.login(iago.email)

zerver/views/streams.py

@@ -167,7 +167,7 @@ def update_stream_backend(
             # Check that the stream name is available (unless we are
             # are only changing the casing of the stream name).
             check_stream_name_available(user_profile.realm, new_name)
-        do_rename_stream(stream, new_name)
+        do_rename_stream(stream, new_name, user_profile)
     if is_announcement_only is not None:
         do_change_stream_announcement_only(stream, is_announcement_only)