feat: adding unenrollments to event bus (#33085)

* feat: adding unenrollments to event bus

* fix: quality fixes

* fix: tweaks to pass tests

* fix: more tweaks for testing

---------

Co-authored-by: John Nagro <jnagro@edx.org>

cms/envs/devstack.py

@@ -303,11 +303,13 @@ def should_show_debug_toolbar(request):  # lint-amnesty, pylint: disable=missing
 #   in the LMS and CMS.
 # .. toggle_tickets: 'https://github.com/openedx/edx-platform/pull/31813'
 FEATURES['ENABLE_SEND_XBLOCK_EVENTS_OVER_BUS'] = True
+FEATURES['ENABLE_SEND_ENROLLMENT_EVENTS_OVER_BUS'] = True
 EVENT_BUS_PRODUCER = 'edx_event_bus_redis.create_producer'
 EVENT_BUS_REDIS_CONNECTION_URL = 'redis://:password@edx.devstack.redis:6379/'
 EVENT_BUS_TOPIC_PREFIX = 'dev'
 EVENT_BUS_CONSUMER = 'edx_event_bus_redis.RedisEventConsumer'
 EVENT_BUS_XBLOCK_LIFECYCLE_TOPIC = 'course-authoring-xblock-lifecycle'
+EVENT_BUS_ENROLLMENT_LIFECYCLE_TOPIC = 'course-authoring-enrollment-lifecycle'
 
 ################# New settings must go ABOVE this line #################
 ########################################################################

common/djangoapps/student/handlers.py

@@ -0,0 +1,25 @@
+"""
+Handlers for student
+"""
+from django.conf import settings
+from django.dispatch import receiver
+
+from openedx_events.event_bus import get_producer
+from openedx_events.learning.signals import (
+    COURSE_UNENROLLMENT_COMPLETED,
+)
+
+
+@receiver(COURSE_UNENROLLMENT_COMPLETED)
+def course_unenrollment_receiver(sender, signal, **kwargs):
+    """
+    Removes user notification preference when user un-enrolls from the course
+    """
+    if settings.FEATURES.get("ENABLE_SEND_ENROLLMENT_EVENTS_OVER_BUS"):
+        get_producer().send(
+            signal=COURSE_UNENROLLMENT_COMPLETED,
+            topic=getattr(settings, "EVENT_BUS_ENROLLMENT_LIFECYCLE_TOPIC", "course-unenrollment-lifecycle"),
+            event_key_field='enrollment.course.course_key',
+            event_data={'enrollment': kwargs.get('enrollment')},
+            event_metadata=kwargs.get('metadata')
+        )

common/djangoapps/student/tests/test_handlers.py

@@ -0,0 +1,67 @@
+"""
+Unit tests for event bus tests for course unenrollments
+"""
+
+import unittest
+from datetime import datetime, timezone
+from unittest import mock
+from uuid import uuid4
+
+from django.test.utils import override_settings
+from common.djangoapps.student.handlers import course_unenrollment_receiver
+from common.djangoapps.student.tests.factories import (
+    UserFactory,
+    CourseEnrollmentFactory,
+)
+
+from openedx_events.data import EventsMetadata
+from openedx_events.learning.signals import COURSE_UNENROLLMENT_COMPLETED
+from pytest import mark
+
+
+@mark.django_db
+class UnenrollmentEventBusTests(unittest.TestCase):
+    """
+    Tests for unenrollment events that interact with the event bus.
+    """
+    @override_settings(ENABLE_SEND_ENROLLMENT_EVENTS_OVER_BUS=False)
+    @mock.patch('common.djangoapps.student.handlers.get_producer', autospec=True)
+    def test_event_disabled(self, mock_producer):
+        """
+        Test to verify that we do not push `CERTIFICATE_CREATED` events to the event bus if the
+        `SEND_CERTIFICATE_CREATED_SIGNAL` setting is disabled.
+        """
+        course_unenrollment_receiver(None, None)
+        mock_producer.assert_not_called()
+
+    @override_settings(FEATURES={'ENABLE_SEND_ENROLLMENT_EVENTS_OVER_BUS': True})
+    @mock.patch('common.djangoapps.student.handlers.get_producer', autospec=True)
+    def test_event_enabled(self, mock_producer):
+        """
+        Test to verify that we push `COURSE_UNENROLLMENT_COMPLETED` events to the event bus.
+        """
+        user = UserFactory()
+        enrollment = CourseEnrollmentFactory(user=user)
+
+        event_metadata = EventsMetadata(
+            event_type=COURSE_UNENROLLMENT_COMPLETED.event_type,
+            id=uuid4(),
+            minorversion=0,
+            source='openedx/lms/web',
+            sourcehost='lms.test',
+            time=datetime.now(timezone.utc)
+        )
+
+        event_kwargs = {
+            'enrollment': enrollment,
+            'metadata': event_metadata
+        }
+        course_unenrollment_receiver(None, COURSE_UNENROLLMENT_COMPLETED, **event_kwargs)
+
+        # verify that the data sent to the event bus matches what we expect
+        print(mock_producer.return_value)
+        print(mock_producer.return_value.send.call_args)
+        data = mock_producer.return_value.send.call_args.kwargs
+        assert data['event_data']['enrollment'] == enrollment
+        assert data['topic'] == 'course-unenrollment-lifecycle'
+        assert data['event_key_field'] == 'enrollment.course.course_key'

openedx/core/djangoapps/notifications/handlers.py

@@ -46,7 +46,7 @@ def on_user_course_unenrollment(enrollment, **kwargs):
         preference = CourseNotificationPreference.objects.get(user__id=user_id, course_id=course_key)
         preference.delete()
     except ObjectDoesNotExist:
-        log.info(f'Notification Preference doesnot exist for {enrollment.user.pii.username} in {course_key}')
+        log.info(f'Notification Preference does not exist for {enrollment.user.pii.username} in {course_key}')
 
 
 @receiver(USER_NOTIFICATION_REQUESTED)