Bszabo/tnl 11230 library content emails (#33899)

* feat: suppress emails

* feat: TNL-11230 No Lib reference

Work around dependency failure

* feat: TNL-11230 cleanup

* feat: TNL-11230 pylint

comment line too long

---------

Co-authored-by: Bernard Szabo <bszabo@edx.org>

cms/djangoapps/cms_user_tasks/signals.py

@@ -2,6 +2,7 @@
 Receivers of signals sent from django-user-tasks
 """
 import logging
+import re
 from urllib.parse import urljoin
 
 from django.dispatch import receiver
@@ -15,6 +16,7 @@ from cms.djangoapps.contentstore.utils import course_import_olx_validation_is_en
 from .tasks import send_task_complete_email
 
 LOGGER = logging.getLogger(__name__)
+LIBRARY_CONTENT_TASK_NAME_TEMPLATE = 'updating .*type@library_content.* from library'
 
 
 @receiver(user_task_stopped, dispatch_uid="cms_user_task_stopped")
@@ -33,6 +35,22 @@ def user_task_stopped_handler(sender, **kwargs):  # pylint: disable=unused-argum
     Returns:
         None
     """
+
+    def is_library_content_update(task_name: str) -> bool:
+        """
+        Decides whether to suppress an end-of-task email on the basis that the just-ended task was a library content
+        XBlock update operation, and that emails following such operations amount to spam
+        Arguments:
+            task_name: The name of the just-ended task. By convention, if this was a library content XBlock update
+            task, then the task name follows the pattern prescribed in LibrarySyncChildrenTask
+            (content_libraries under openedx) 'Updating {key} from library'. Moreover, the block type
+            in the task name is always of type 'library_content' for such operations
+        Returns:
+            True if the end-of-task email should be suppressed
+        """
+        p = re.compile(LIBRARY_CONTENT_TASK_NAME_TEMPLATE)
+        return p.match(task_name)
+
     def get_olx_validation_from_artifact():
         """
         Get olx validation error if available for current task.
@@ -47,9 +65,17 @@ def user_task_stopped_handler(sender, **kwargs):  # pylint: disable=unused-argum
             return olx_artifact.text
 
     status = kwargs['status']
+
     # Only send email when the entire task is complete, should only send when
     # a chain / chord / etc completes, not on sub-tasks.
     if status.parent is None:
+        task_name = status.name.lower()
+
+        # Also suppress emails on library content XBlock updates (too much like spam)
+        if is_library_content_update(task_name):
+            LOGGER.info(f"Suppressing end-of-task email on task {task_name}")
+            return
+
         # `name` and `status` are not unique, first is our best guess
         artifact = UserTaskArtifact.objects.filter(status=status, name="BASE_URL").first()
 
@@ -61,7 +87,6 @@ def user_task_stopped_handler(sender, **kwargs):  # pylint: disable=unused-argum
             )
 
         user_email = status.user.email
-        task_name = status.name.lower()
         olx_validation_text = get_olx_validation_from_artifact()
         task_args = [task_name, str(status.state_text), user_email, detail_url, olx_validation_text]
         try:

cms/djangoapps/cms_user_tasks/tests.py

@@ -208,6 +208,19 @@ class TestUserTaskStopped(APITestCase):
         self.assert_msg_subject(msg)
         self.assert_msg_body_fragments(msg, body_fragments)
 
+    def test_email_not_sent_with_libary_content_update(self):
+        """
+        Check the signal receiver and email sending.
+        """
+        UserTaskArtifact.objects.create(
+            status=self.status, name='BASE_URL', url='https://test.edx.org/'
+        )
+        end_of_task_status = self.status
+        end_of_task_status.name = "updating block-v1:course+type@library_content+block@uuid from library"
+        user_task_stopped.send(sender=UserTaskStatus, status=end_of_task_status)
+
+        self.assertEqual(len(mail.outbox), 0)
+
     def test_email_sent_with_olx_validations_with_config_enabled(self):
         """
         Tests that email is sent with olx validation errors.