Store Discussions ID Map on CourseDiscussionSettings model when course publish signal is fired.

common/djangoapps/django_comment_common/migrations/0006_coursediscussionsettings_discussions_id_map.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.12 on 2018-04-23 21:09
+from __future__ import unicode_literals
+
+from django.db import migrations
+import jsonfield.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('django_comment_common', '0005_coursediscussionsettings'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='coursediscussionsettings',
+            name='discussions_id_map',
+            field=jsonfield.fields.JSONField(blank=True, help_text=b'Key/value store mapping discussion IDs to discussion XBlock usage keys.', null=True),
+        ),
+    ]

common/djangoapps/django_comment_common/models.py

@@ -8,6 +8,7 @@ from django.db import models
 from django.db.models.signals import post_save
 from django.dispatch import receiver
 from django.utils.translation import ugettext_noop
+from jsonfield.fields import JSONField
 from opaque_keys.edx.django.models import CourseKeyField
 from six import text_type
 
@@ -180,6 +181,11 @@ class CourseDiscussionSettings(models.Model):
         db_index=True,
         help_text="Which course are these settings associated with?",
     )
+    discussions_id_map = JSONField(
+        null=True,
+        blank=True,
+        help_text="Key/value store mapping discussion IDs to discussion XBlock usage keys.",
+    )
     always_divide_inline_discussions = models.BooleanField(default=False)
     _divided_discussions = models.TextField(db_column='divided_discussions', null=True, blank=True)  # JSON list
 

common/djangoapps/django_comment_common/utils.py

@@ -139,11 +139,18 @@ def set_course_discussion_settings(course_key, **kwargs):
         divided_discussions (list): List of discussion ids.
         division_scheme (str): `CourseDiscussionSettings.NONE`, `CourseDiscussionSettings.COHORT`,
             or `CourseDiscussionSettings.ENROLLMENT_TRACK`
+        discussions_id_map (dict): Dict containing discussion IDs as keys and the associated discussion
+            XBlock usage keys as values.
 
     Returns:
         A CourseDiscussionSettings object.
     """
-    fields = {'division_scheme': basestring, 'always_divide_inline_discussions': bool, 'divided_discussions': list}
+    fields = {
+        'division_scheme': basestring,
+        'always_divide_inline_discussions': bool,
+        'divided_discussions': list,
+        'discussions_id_map': dict,
+    }
     course_discussion_settings = get_course_discussion_settings(course_key)
     for field, field_type in fields.items():
         if field in kwargs:

lms/djangoapps/discussion/settings/common.py

@@ -4,3 +4,7 @@
 def plugin_settings(settings):
     """Settings for the discussions plugin. """
     settings.FEATURES['ALLOW_HIDING_DISCUSSION_TAB'] = False
+    settings.DISCUSSION_SETTINGS = {
+        'MAX_COMMENT_DEPTH': 2,
+        'COURSE_PUBLISH_TASK_DELAY': 30,
+    }

lms/djangoapps/discussion/signals/handlers.py

@@ -3,13 +3,15 @@ Signal handlers related to discussions.
 """
 import logging
 
+from django.conf import settings
 from django.dispatch import receiver
-from opaque_keys.edx.keys import CourseKey
 
 from django_comment_common import signals
 from lms.djangoapps.discussion import tasks
+from opaque_keys.edx.locator import LibraryLocator
 from openedx.core.djangoapps.site_configuration.models import SiteConfiguration
 from openedx.core.djangoapps.theming.helpers import get_current_site
+from xmodule.modulestore.django import SignalHandler
 
 
 log = logging.getLogger(__name__)
@@ -18,6 +20,25 @@ log = logging.getLogger(__name__)
 ENABLE_FORUM_NOTIFICATIONS_FOR_SITE_KEY = 'enable_forum_notifications'
 
 
+@receiver(SignalHandler.course_published)
+def update_discussions_on_course_publish(sender, course_key, **kwargs):  # pylint: disable=unused-argument
+    """
+    Catches the signal that a course has been published in the module
+    store and creates/updates the corresponding cache entry.
+    Ignores publish signals from content libraries.
+    """
+    if isinstance(course_key, LibraryLocator):
+        return
+
+    context = {
+        'course_id': unicode(course_key),
+    }
+    tasks.update_discussions_map.apply_async(
+        args=[context],
+        countdown=settings.DISCUSSION_SETTINGS['COURSE_PUBLISH_TASK_DELAY'],
+    )
+
+
 @receiver(signals.comment_created)
 def send_discussion_email_notification(sender, user, post, **kwargs):
     current_site = get_current_site()

lms/djangoapps/discussion/tasks.py

@@ -12,12 +12,13 @@ from django.contrib.auth.models import User
 from django.contrib.sites.models import Site
 
 from celery_utils.logged_task import LoggedTask
+from django_comment_common.utils import set_course_discussion_settings
 from edx_ace import ace
 from edx_ace.utils import date
 from edx_ace.message import MessageType
 from edx_ace.recipient import Recipient
 from opaque_keys.edx.keys import CourseKey
-from lms.djangoapps.django_comment_client.utils import permalink
+from lms.djangoapps.django_comment_client.utils import permalink, get_accessible_discussion_xblocks_by_course_id
 import lms.lib.comment_client as cc
 
 from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
@@ -32,6 +33,24 @@ DEFAULT_LANGUAGE = 'en'
 ROUTING_KEY = getattr(settings, 'ACE_ROUTING_KEY', None)
 
 
+@task(base=LoggedTask)
+def update_discussions_map(context):
+    """
+    Updates the mapping between discussion_id to discussion block usage key
+    for all discussion blocks in the given course.
+
+    context is a dict that contains:
+        course_id (string): identifier of the course
+    """
+    course_key = CourseKey.from_string(context['course_id'])
+    discussion_blocks = get_accessible_discussion_xblocks_by_course_id(course_key, include_all=True)
+    discussions_id_map = {
+        discussion_block.discussion_id: unicode(discussion_block.location)
+        for discussion_block in discussion_blocks
+    }
+    set_course_discussion_settings(course_key, discussions_id_map=discussions_id_map)
+
+
 class ResponseNotification(MessageType):
     pass
 

lms/djangoapps/discussion/tests/test_signals.py

@@ -1,10 +1,12 @@
 from django.test import TestCase
 import mock
 
-from django_comment_common import signals
+from django_comment_common import signals, models
 from lms.djangoapps.discussion.signals.handlers import ENABLE_FORUM_NOTIFICATIONS_FOR_SITE_KEY
+import openedx.core.djangoapps.request_cache as request_cache
 from openedx.core.djangoapps.site_configuration.tests.factories import SiteFactory, SiteConfigurationFactory
-from openedx.core.djangoapps.waffle_utils.testutils import override_waffle_flag
+from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
+from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory
 
 
 class SendMessageHandlerTestCase(TestCase):
@@ -56,3 +58,39 @@ class SendMessageHandlerTestCase(TestCase):
         signals.comment_created.send(sender=self.sender, user=self.user, post=self.post)
 
         self.assertFalse(mock_send_message.called)
+
+
+class CoursePublishHandlerTestCase(ModuleStoreTestCase):
+    """
+    Tests for discussion updates on course publish.
+    """
+    ENABLED_SIGNALS = ['course_published']
+
+    def test_discussion_id_map_updates_on_publish(self):
+        course_key_args = dict(org='org', course='number', run='run')
+        course_key = self.store.make_course_key(**course_key_args)
+
+        with self.assertRaises(models.CourseDiscussionSettings.DoesNotExist):
+            models.CourseDiscussionSettings.objects.get(course_id=course_key)
+
+        # create course
+        course = CourseFactory(emit_signals=True, **course_key_args)
+        self.assertEqual(course.id, course_key)
+        self._assert_discussion_id_map(course_key, {})
+
+        # create discussion block
+        request_cache.clear_cache(name=None)
+        discussion_id = 'discussion1'
+        discussion_block = ItemFactory.create(
+            parent_location=course.location,
+            category="discussion",
+            discussion_id=discussion_id,
+        )
+        self._assert_discussion_id_map(course_key, {discussion_id: str(discussion_block.location)})
+
+    def _assert_discussion_id_map(self, course_key, expected_map):
+        """
+        Verifies the discussion ID map for the given course matches the expected value.
+        """
+        discussion_settings = models.CourseDiscussionSettings.objects.get(course_id=course_key)
+        self.assertDictEqual(discussion_settings.discussions_id_map, expected_map)

lms/djangoapps/discussion/tests/test_tasks.py

@@ -5,7 +5,6 @@ from datetime import datetime, timedelta
 import json
 import math
 
-from crum import CurrentRequestUserMiddleware
 import ddt
 from django.contrib.sites.models import Site
 import mock
@@ -22,8 +21,6 @@ from lms.djangoapps.discussion.tasks import _should_send_message, _track_notific
 from openedx.core.djangoapps.content.course_overviews.tests.factories import CourseOverviewFactory
 from openedx.core.djangoapps.ace_common.template_context import get_base_template_context
 from openedx.core.djangoapps.site_configuration.tests.factories import SiteConfigurationFactory
-from openedx.core.djangoapps.theming.middleware import CurrentSiteThemeMiddleware
-from openedx.core.djangoapps.waffle_utils.testutils import override_waffle_flag
 from openedx.core.lib.celery.task_utils import emulate_http_request
 from student.tests.factories import CourseEnrollmentFactory, UserFactory
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase

lms/djangoapps/django_comment_client/base/tests.py

@@ -406,8 +406,8 @@ class ViewsQueryCountTestCase(
         return inner
 
     @ddt.data(
-        (ModuleStoreEnum.Type.mongo, 3, 4, 35),
-        (ModuleStoreEnum.Type.split, 3, 13, 35),
+        (ModuleStoreEnum.Type.mongo, 3, 3, 30),
+        (ModuleStoreEnum.Type.split, 3, 11, 30),
     )
     @ddt.unpack
     @count_queries
@@ -415,8 +415,8 @@ class ViewsQueryCountTestCase(
         self.create_thread_helper(mock_request)
 
     @ddt.data(
-        (ModuleStoreEnum.Type.mongo, 3, 3, 31),
-        (ModuleStoreEnum.Type.split, 3, 10, 31),
+        (ModuleStoreEnum.Type.mongo, 3, 2, 26),
+        (ModuleStoreEnum.Type.split, 3, 8, 26),
     )
     @ddt.unpack
     @count_queries

lms/djangoapps/django_comment_client/utils.py

@@ -125,10 +125,10 @@ def get_accessible_discussion_xblocks(course, user, include_all=False):  # pylin
 
 
 @request_cached
-def get_accessible_discussion_xblocks_by_course_id(course_id, user, include_all=False):  # pylint: disable=invalid-name
+def get_accessible_discussion_xblocks_by_course_id(course_id, user=None, include_all=False):  # pylint: disable=invalid-name
     """
-    Return a list of all valid discussion xblocks in this course that
-    are accessible to the given user.
+    Return a list of all valid discussion xblocks in this course.
+    Checks for the given user's access if include_all is False.
     """
     all_xblocks = modulestore().get_items(course_id, qualifiers={'category': 'discussion'}, include_orphans=False)
 

lms/envs/common.py

@@ -59,10 +59,6 @@ PLATFORM_TWITTER_ACCOUNT = "@YourPlatformTwitterAccount"
 
 ENABLE_JASMINE = False
 
-DISCUSSION_SETTINGS = {
-    'MAX_COMMENT_DEPTH': 2,
-}
-
 LMS_ROOT_URL = "http://localhost:8000"
 LMS_INTERNAL_ROOT_URL = LMS_ROOT_URL
 LMS_ENROLLMENT_API_PATH = "/api/enrollment/v1/"