MA-779 Update student dashboard to use CourseOverview

common/djangoapps/student/helpers.py

@@ -23,8 +23,9 @@ VERIFY_STATUS_MISSED_DEADLINE = "verify_missed_deadline"
 VERIFY_STATUS_NEED_TO_REVERIFY = "verify_need_to_reverify"
 
 
-def check_verify_status_by_course(user, course_enrollment_pairs, all_course_modes):
-    """Determine the per-course verification statuses for a given user.
+def check_verify_status_by_course(user, course_enrollments, all_course_modes):
+    """
+    Determine the per-course verification statuses for a given user.
 
     The possible statuses are:
         * VERIFY_STATUS_NEED_TO_VERIFY: The student has not yet submitted photos for verification.
@@ -46,8 +47,7 @@ def check_verify_status_by_course(user, course_enrollment_pairs, all_course_mode
 
     Arguments:
         user (User): The currently logged-in user.
-        course_enrollment_pairs (list): The courses the user is enrolled in.
-            The list should contain tuples of `(Course, CourseEnrollment)`.
+        course_enrollments (list[CourseEnrollment]): The courses the user is enrolled in.
         all_course_modes (list): List of all course modes for the student's enrolled courses,
             including modes that have expired.
 
@@ -75,15 +75,15 @@ def check_verify_status_by_course(user, course_enrollment_pairs, all_course_mode
 
     recent_verification_datetime = None
 
-    for course, enrollment in course_enrollment_pairs:
+    for enrollment in course_enrollments:
 
         # Get the verified mode (if any) for this course
         # We pass in the course modes we have already loaded to avoid
         # another database hit, as well as to ensure that expired
         # course modes are included in the search.
         verified_mode = CourseMode.verified_mode_for_course(
-            course.id,
-            modes=all_course_modes[course.id]
+            enrollment.course_id,
+            modes=all_course_modes[enrollment.course_id]
         )
 
         # If no verified mode has ever been offered, or the user hasn't enrolled
@@ -156,7 +156,7 @@ def check_verify_status_by_course(user, course_enrollment_pairs, all_course_mode
                 if deadline is not None and deadline > now:
                     days_until_deadline = (deadline - now).days
 
-                status_by_course[course.id] = {
+                status_by_course[enrollment.course_id] = {
                     'status': status,
                     'days_until_deadline': days_until_deadline
                 }

common/djangoapps/student/models.py

@@ -850,6 +850,13 @@ class CourseEnrollment(models.Model):
         unique_together = (('user', 'course_id'),)
         ordering = ('user', 'course_id')
 
+    def __init__(self, *args, **kwargs):
+        super(CourseEnrollment, self).__init__(*args, **kwargs)
+
+        # Private variable for storing course_overview to minimize calls to the database.
+        # When the property .course_overview is accessed for the first time, this variable will be set.
+        self._course_overview = None
+
     def __unicode__(self):
         return (
             "[CourseEnrollment] {}: {} ({}); active: ({})"
@@ -1318,10 +1325,21 @@ class CourseEnrollment(models.Model):
     @property
     def course_overview(self):
         """
-        Return a CourseOverview of this enrollment's course.
+        Returns a CourseOverview of the course to which this enrollment refers.
+        Returns None if an error occurred while trying to load the course.
+
+        Note:
+            If the course is re-published within the lifetime of this
+            CourseEnrollment object, then the value of this property will
+            become stale.
        """
+        if not self._course_overview:
             from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
-        return CourseOverview.get_from_id(self.course_id)
+            try:
+                self._course_overview = CourseOverview.get_from_id(self.course_id)
+            except (CourseOverview.DoesNotExist, IOError):
+                self._course_overview = None
+        return self._course_overview
 
     def is_verified_enrollment(self):
         """

common/djangoapps/student/tests/test_course_listing.py

@@ -14,7 +14,7 @@ from xmodule.modulestore.django import modulestore
 from xmodule.error_module import ErrorDescriptor
 from django.test.client import Client
 from student.models import CourseEnrollment
-from student.views import get_course_enrollment_pairs
+from student.views import get_course_enrollments
 from util.milestones_helpers import (
     get_pre_requisite_courses_not_completed,
     set_prerequisite_courses,
@@ -73,13 +73,13 @@ class TestCourseListing(ModuleStoreTestCase):
         self._create_course_with_access_groups(course_location)
 
         # get dashboard
-        courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+        courses_list = list(get_course_enrollments(self.student, None, []))
         self.assertEqual(len(courses_list), 1)
-        self.assertEqual(courses_list[0][0].id, course_location)
+        self.assertEqual(courses_list[0].course_id, course_location)
 
         CourseEnrollment.unenroll(self.student, course_location)
         # get dashboard
-        courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+        courses_list = list(get_course_enrollments(self.student, None, []))
         self.assertEqual(len(courses_list), 0)
 
     def test_errored_course_regular_access(self):
@@ -95,7 +95,7 @@ class TestCourseListing(ModuleStoreTestCase):
             self.assertIsInstance(modulestore().get_course(course_key), ErrorDescriptor)
 
             # get courses through iterating all courses
-            courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+            courses_list = list(get_course_enrollments(self.student, None, []))
             self.assertEqual(courses_list, [])
 
     def test_course_listing_errored_deleted_courses(self):
@@ -112,9 +112,9 @@ class TestCourseListing(ModuleStoreTestCase):
         self._create_course_with_access_groups(course_location, default_store=ModuleStoreEnum.Type.mongo)
         mongo_store.delete_course(course_location, ModuleStoreEnum.UserID.test)
 
-        courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+        courses_list = list(get_course_enrollments(self.student, None, []))
         self.assertEqual(len(courses_list), 1, courses_list)
-        self.assertEqual(courses_list[0][0].id, good_location)
+        self.assertEqual(courses_list[0].course_id, good_location)
 
     @mock.patch.dict("django.conf.settings.FEATURES", {'ENABLE_PREREQUISITE_COURSES': True, 'MILESTONES_APP': True})
     def test_course_listing_has_pre_requisite_courses(self):
@@ -142,9 +142,11 @@ class TestCourseListing(ModuleStoreTestCase):
 
         set_prerequisite_courses(course_location, pre_requisite_courses)
         # get dashboard
-        course_enrollment_pairs = list(get_course_enrollment_pairs(self.student, None, []))
-        courses_having_prerequisites = frozenset(course.id for course, _enrollment in course_enrollment_pairs
-                                                 if course.pre_requisite_courses)
+        course_enrollments = list(get_course_enrollments(self.student, None, []))
+        courses_having_prerequisites = frozenset(
+            enrollment.course_id for enrollment in course_enrollments
+            if enrollment.course_overview.pre_requisite_courses
+        )
         courses_requirements_not_met = get_pre_requisite_courses_not_completed(
             self.student,
             courses_having_prerequisites

common/djangoapps/student/tests/test_recent_enrollments.py

@@ -15,7 +15,7 @@ from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
 from xmodule.modulestore.tests.factories import CourseFactory
 from course_modes.tests.factories import CourseModeFactory
 from student.models import CourseEnrollment, DashboardConfiguration
-from student.views import get_course_enrollment_pairs, _get_recently_enrolled_courses
+from student.views import get_course_enrollments, _get_recently_enrolled_courses  # pylint: disable=protected-access
 
 
 @unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
@@ -67,7 +67,7 @@ class TestRecentEnrollments(ModuleStoreTestCase):
         self._configure_message_timeout(60)
 
         # get courses through iterating all courses
-        courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+        courses_list = list(get_course_enrollments(self.student, None, []))
         self.assertEqual(len(courses_list), 2)
 
         recent_course_list = _get_recently_enrolled_courses(courses_list)
@@ -78,7 +78,7 @@ class TestRecentEnrollments(ModuleStoreTestCase):
         Tests that the recent enrollment list is empty if configured to zero seconds.
         """
         self._configure_message_timeout(0)
-        courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+        courses_list = list(get_course_enrollments(self.student, None, []))
         self.assertEqual(len(courses_list), 2)
 
         recent_course_list = _get_recently_enrolled_courses(courses_list)
@@ -106,16 +106,16 @@ class TestRecentEnrollments(ModuleStoreTestCase):
             enrollment.save()
             courses.append(course)
 
-        courses_list = list(get_course_enrollment_pairs(self.student, None, []))
+        courses_list = list(get_course_enrollments(self.student, None, []))
         self.assertEqual(len(courses_list), 6)
 
         recent_course_list = _get_recently_enrolled_courses(courses_list)
         self.assertEqual(len(recent_course_list), 5)
 
-        self.assertEqual(recent_course_list[1][0], courses[0])
-        self.assertEqual(recent_course_list[2][0], courses[1])
-        self.assertEqual(recent_course_list[3][0], courses[2])
-        self.assertEqual(recent_course_list[4][0], courses[3])
+        self.assertEqual(recent_course_list[1].course, courses[0])
+        self.assertEqual(recent_course_list[2].course, courses[1])
+        self.assertEqual(recent_course_list[3].course, courses[2])
+        self.assertEqual(recent_course_list[4].course, courses[3])
 
     def test_dashboard_rendering(self):
         """

common/djangoapps/student/tests/tests.py

 # -*- coding: utf-8 -*-
 """
-This file demonstrates writing tests using the unittest module. These will pass
-when you run "manage.py test".
-
-Replace this with more appropriate tests for your application.
+Miscellaneous tests for the student app.
 """
 from datetime import datetime, timedelta
 import logging
@@ -28,8 +25,8 @@ from student.views import (process_survey_link, _cert_info,
 from student.tests.factories import UserFactory, CourseModeFactory
 from util.testing import EventTestMixin
 from util.model_utils import USER_SETTINGS_CHANGED_EVENT_NAME
-from xmodule.modulestore.tests.factories import CourseFactory
-from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
+from xmodule.modulestore.tests.factories import CourseFactory, check_mongo_calls
+from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase, ModuleStoreEnum
 
 # These imports refer to lms djangoapps.
 # Their testcases are only run under lms.
@@ -193,6 +190,7 @@ class CourseEndingTest(TestCase):
         self.assertIsNone(_cert_info(user, course2, cert_status, course_mode))
 
 
+@ddt.ddt
 class DashboardTest(ModuleStoreTestCase):
     """
     Tests for dashboard utility functions
@@ -487,6 +485,48 @@ class DashboardTest(ModuleStoreTestCase):
         )
         self.assertContains(response, expected_url)
 
+    @unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
+    @ddt.data((ModuleStoreEnum.Type.mongo, 1), (ModuleStoreEnum.Type.split, 3))
+    @ddt.unpack
+    def test_dashboard_metadata_caching(self, modulestore_type, expected_mongo_calls):
+        """
+        Check that the student dashboard makes use of course metadata caching.
+
+        The first time the student dashboard displays a specific course, it will
+        make a call to the module store. After that first request, though, the
+        course's metadata should be cached as a CourseOverview.
+
+        Arguments:
+            modulestore_type (ModuleStoreEnum.Type): Type of modulestore to create
+                test course in.
+            expected_mongo_calls (int >=0): Number of MongoDB queries expected for
+                a single call to the module store.
+
+        Note to future developers:
+            If you break this test so that the "check_mongo_calls(0)" fails,
+            please do NOT change it to "check_mongo_calls(n>1)". Instead, change
+            your code to not load courses from the module store. This may
+            involve adding fields to CourseOverview so that loading a full
+            CourseDescriptor isn't necessary.
+        """
+        # Create a course, log in the user, and enroll them in the course.
+        test_course = CourseFactory.create(default_store=modulestore_type)
+        self.client.login(username="jack", password="test")
+        CourseEnrollment.enroll(self.user, test_course.id)
+
+        # The first request will result in a modulestore query.
+        with check_mongo_calls(expected_mongo_calls):
+            response_1 = self.client.get(reverse('dashboard'))
+            self.assertEquals(response_1.status_code, 200)
+
+        # Subsequent requests will only result in SQL queries to load the
+        # CourseOverview object that has been created.
+        with check_mongo_calls(0):
+            response_2 = self.client.get(reverse('dashboard'))
+            self.assertEquals(response_2.status_code, 200)
+            response_3 = self.client.get(reverse('dashboard'))
+            self.assertEquals(response_3.status_code, 200)
+
 
 class UserSettingsEventTestMixin(EventTestMixin):
     """

lms/djangoapps/certificates/api.py

@@ -12,6 +12,7 @@ from django.core.urlresolvers import reverse
 from eventtracking import tracker
 from opaque_keys.edx.keys import CourseKey
 
+from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
 from xmodule.modulestore.django import modulestore
 
 from certificates.models import (
@@ -216,13 +217,18 @@ def generate_example_certificates(course_key):
 
 def has_html_certificates_enabled(course_key, course=None):
     """
-    It determines if course has html certificates enabled
+    Determine if a course has html certificates enabled.
+
+    Arguments:
+        course_key (CourseKey|str): A course key or a string representation
+            of one.
+        course (CourseDescriptor|CourseOverview): A course.
     """
     html_certificates_enabled = False
     try:
         if not isinstance(course_key, CourseKey):
             course_key = CourseKey.from_string(course_key)
-        course = course if course else modulestore().get_course(course_key, depth=0)
+        course = course if course else CourseOverview.get_from_id(course_key)
         if settings.FEATURES.get('CERTIFICATES_HTML_VIEW', False) and course.cert_html_view_enabled:
             html_certificates_enabled = True
     except:  # pylint: disable=bare-except

lms/djangoapps/courseware/courses.py

@@ -152,6 +152,16 @@ def find_file(filesystem, dirs, filename):
     raise ResourceNotFoundError(u"Could not find {0}".format(filename))
 
 
+def get_course_university_about_section(course):  # pylint: disable=invalid-name
+    """
+    Returns a snippet of HTML displaying the course's university.
+
+    Arguments:
+        course (CourseDescriptor|CourseOverview): A course.
+    """
+    return course.display_org_with_default
+
+
 def get_course_about_section(course, section_key):
     """
     This returns the snippet of html to be rendered on the course about page,
@@ -227,7 +237,7 @@ def get_course_about_section(course, section_key):
     elif section_key == "title":
         return course.display_name_with_default
     elif section_key == "university":
-        return course.display_org_with_default
+        return get_course_university_about_section(course)
     elif section_key == "number":
         return course.display_number_with_default
 

lms/templates/ccx/_dashboard_ccx_listing.html

-<%page args="ccx, membership, course, show_courseware_link, is_course_blocked" />
+<%page args="ccx, membership, course_overview, show_courseware_link, is_course_blocked" />
 
 <%!
 from django.utils.translation import ugettext as _
@@ -7,7 +7,7 @@ from courseware.courses import course_image_url, get_course_about_section
 from ccx_keys.locator import CCXLocator
 %>
 <%
-  ccx_target = reverse('info', args=[CCXLocator.from_course_locator(course.id, ccx.id)])
+  ccx_target = reverse('info', args=[CCXLocator.from_course_locator(course_overview.id, ccx.id)])
 %>
 <li class="course-item">
   <article class="course">
@@ -16,16 +16,16 @@ from ccx_keys.locator import CCXLocator
         % if show_courseware_link:
           % if not is_course_blocked:
               <a href="${ccx_target}" class="cover">
-                <img src="${course_image_url(course)}" class="course-image" alt="${_('{course_number} {ccx_name} Cover Image').format(course_number=course.number, ccx_name=ccx.display_name) |h}" />
+                <img src="${course_overview.course_image_url}" class="course-image" alt="${_('{course_number} {ccx_name} Cover Image').format(course_number=course_overview.number, ccx_name=ccx.display_name) |h}" />
               </a>
           % else:
               <a class="fade-cover">
-                <img src="${course_image_url(course)}" class="course-image" alt="${_('{course_number} {ccx_name} Cover Image').format(course_number=course.number, ccx_name=ccx.display_name) |h}" />
+                <img src="${course_overview.course_image_url}" class="course-image" alt="${_('{course_number} {ccx_name} Cover Image').format(course_number=course_overview.number, ccx_name=ccx.display_name) |h}" />
               </a>
           % endif
         % else:
           <a class="cover">
-            <img src="${course_image_url(course)}" class="course-image" alt="${_('{course_number} {ccx_name} Cover Image').format(course_number=course.number, ccx_name=ccx.display_name) |h}" />
+            <img src="${course_overview.course_image_url}" class="course-image" alt="${_('{course_number} {ccx_name} Cover Image').format(course_number=course_overview.number, ccx_name=ccx.display_name) |h}" />
           </a>
         % endif
       </div>
@@ -43,7 +43,7 @@ from ccx_keys.locator import CCXLocator
         </h3>
         <div class="course-info">
           <span class="info-university">${get_course_about_section(course, 'university')} - </span>
-          <span class="info-course-id">${course.display_number_with_default | h}</span>
+          <span class="info-course-id">${course_overview.display_number_with_default | h}</span>
           <span class="info-date-block" data-tooltip="Hi">
           % if ccx.has_ended():
             ${_("Ended - {end_date}").format(end_date=ccx.end_datetime_text("SHORT_DATE"))}

lms/templates/dashboard.html

@@ -70,28 +70,28 @@ from django.core.urlresolvers import reverse
     </header>
 
 
-    % if len(course_enrollment_pairs) > 0:
+    % if len(course_enrollments) > 0:
       <ul class="listing-courses">
       <% share_settings = settings.FEATURES.get('SOCIAL_SHARING_SETTINGS', {}) %>
-      % for dashboard_index, (course, enrollment) in enumerate(course_enrollment_pairs):
-        <% show_courseware_link = (course.id in show_courseware_links_for) %>
-        <% cert_status = cert_statuses.get(course.id) %>
-        <% credit_status = credit_statuses.get(course.id) %>
-        <% show_email_settings = (course.id in show_email_settings_for) %>
-        <% course_mode_info = all_course_modes.get(course.id) %>
-        <% show_refund_option = (course.id in show_refund_option_for) %>
-        <% is_paid_course = (course.id in enrolled_courses_either_paid) %>
-        <% is_course_blocked = (course.id in block_courses) %>
-        <% course_verification_status = verification_status_by_course.get(course.id, {}) %>
-        <% course_requirements = courses_requirements_not_met.get(course.id) %>
-        <%include file='dashboard/_dashboard_course_listing.html' args="course=course, enrollment=enrollment, show_courseware_link=show_courseware_link, cert_status=cert_status, credit_status=credit_status, show_email_settings=show_email_settings, course_mode_info=course_mode_info, show_refund_option = show_refund_option, is_paid_course = is_paid_course, is_course_blocked = is_course_blocked, verification_status=course_verification_status, course_requirements=course_requirements, dashboard_index=dashboard_index, share_settings=share_settings, user=user" />
+      % for dashboard_index, enrollment in enumerate(course_enrollments):
+        <% show_courseware_link = (enrollment.course_id in show_courseware_links_for) %>
+        <% cert_status = cert_statuses.get(enrollment.course_id) %>
+        <% credit_status = credit_statuses.get(enrollment.course_id) %>
+        <% show_email_settings = (enrollment.course_id in show_email_settings_for) %>
+        <% course_mode_info = all_course_modes.get(enrollment.course_id) %>
+        <% show_refund_option = (enrollment.course_id in show_refund_option_for) %>
+        <% is_paid_course = (enrollment.course_id in enrolled_courses_either_paid) %>
+        <% is_course_blocked = (enrollment.course_id in block_courses) %>
+        <% course_verification_status = verification_status_by_course.get(enrollment.course_id, {}) %>
+        <% course_requirements = courses_requirements_not_met.get(enrollment.course_id) %>
+        <%include file='dashboard/_dashboard_course_listing.html' args="course_overview=enrollment.course_overview, enrollment=enrollment, show_courseware_link=show_courseware_link, cert_status=cert_status, credit_status=credit_status, show_email_settings=show_email_settings, course_mode_info=course_mode_info, show_refund_option=show_refund_option, is_paid_course=is_paid_course, is_course_blocked=is_course_blocked, verification_status=course_verification_status, course_requirements=course_requirements, dashboard_index=dashboard_index, share_settings=share_settings, user=user" />
       % endfor
 
       % if settings.FEATURES.get('CUSTOM_COURSES_EDX', False):
         % for ccx, membership, course in ccx_membership_triplets:
           <% show_courseware_link = ccx.has_started() %>
           <% is_course_blocked = False %>
-          <%include file='ccx/_dashboard_ccx_listing.html' args="ccx=ccx, membership=membership, course=course, show_courseware_link=show_courseware_link, is_course_blocked=is_course_blocked" />
+          <%include file='ccx/_dashboard_ccx_listing.html' args="ccx=ccx, membership=membership, course_overview=enrollment.course_overview, show_courseware_link=show_courseware_link, is_course_blocked=is_course_blocked" />
         % endfor
       % endif
 

lms/templates/dashboard/_dashboard_certificate_information.html

-<%page args="cert_status, course, enrollment" />
+<%page args="cert_status, course_overview, enrollment" />
 
 <%!
 from django.utils.translation import ugettext as _
@@ -7,11 +7,11 @@ from course_modes.models import CourseMode
 <%namespace name='static' file='../static_content.html'/>
 
 <%
-  cert_name_short = course.cert_name_short
+  cert_name_short = course_overview.cert_name_short
   if cert_name_short == "":
     cert_name_short = settings.CERT_NAME_SHORT
 
-  cert_name_long = course.cert_name_long
+  cert_name_long = course_overview.cert_name_long
   if cert_name_long == "":
     cert_name_long = settings.CERT_NAME_LONG
 %>
@@ -35,7 +35,7 @@ else:
   <span class="grade-value">${"{0:.0f}%".format(float(cert_status['grade'])*100)}</span>.
     % if cert_status['status'] == 'notpassing' and enrollment.mode != 'audit':
        ${_("Grade required for a {cert_name_short}:").format(cert_name_short=cert_name_short)} <span class="grade-value">
-         ${"{0:.0f}%".format(float(course.lowest_passing_grade)*100)}</span>.
+         ${"{0:.0f}%".format(float(course_overview.lowest_passing_grade)*100)}</span>.
     % elif cert_status['status'] == 'restricted' and enrollment.mode == 'verified':
     <p class="message-copy">
       ${_("Your verified {cert_name_long} is being held pending confirmation that the issuance of your {cert_name_short} is in compliance with strict U.S. embargoes on Iran, Cuba, Syria and Sudan. If you think our system has mistakenly identified you as being connected with one of those countries, please let us know by contacting {email}. If you would like a refund on your {cert_name_long}, please contact our billing address {billing_email}").format(email='<a class="contact-link" href="mailto:{email}">{email}</a>.'.format(email=settings.CONTACT_EMAIL), billing_email='<a class="contact-link" href="mailto:{email}">{email}</a>'.format(email=settings.PAYMENT_SUPPORT_EMAIL), cert_name_short=cert_name_short, cert_name_long=cert_name_long)}
@@ -88,7 +88,7 @@ else:
       <li class="action action-share">
         <a class="action-linkedin-profile" target="_blank" href="${cert_status['linked_in_url']}"
          title="${_('Add Certificate to LinkedIn Profile')}"
-         data-course-id="${unicode(course.id)}"
+         data-course-id="${unicode(course_overview.id)}"
          data-certificate-mode="${cert_status['mode']}"
         >
           <img class="action-linkedin-profile-img"

openedx/core/djangoapps/content/course_overviews/migrations/0003_add_cert_html_view_enabled.py

+# -*- coding: utf-8 -*-
+from south.utils import datetime_utils as datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding field 'CourseOverview.cert_html_view_enabled'
+
+        # The default value for the cert_html_view_eanbled column is False.
+        # However, for courses in the table for which cert_html_view_enabled
+        # should be True, this would be invalid. So, we must clear the
+        # table before adding the new column.
+
+        db.clear_table('course_overviews_courseoverview')
+        db.add_column('course_overviews_courseoverview', 'cert_html_view_enabled',
+                      self.gf('django.db.models.fields.BooleanField')(default=False),
+                      keep_default=False)
+
+
+    def backwards(self, orm):
+        # Deleting field 'CourseOverview.cert_html_view_enabled'
+        db.delete_column('course_overviews_courseoverview', 'cert_html_view_enabled')
+
+
+    models = {
+        'course_overviews.courseoverview': {
+            'Meta': {'object_name': 'CourseOverview'},
+            '_location': ('xmodule_django.models.UsageKeyField', [], {'max_length': '255'}),
+            '_pre_requisite_courses_json': ('django.db.models.fields.TextField', [], {}),
+            'advertised_start': ('django.db.models.fields.TextField', [], {'null': 'True'}),
+            'cert_html_view_enabled': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'cert_name_long': ('django.db.models.fields.TextField', [], {}),
+            'cert_name_short': ('django.db.models.fields.TextField', [], {}),
+            'certificates_display_behavior': ('django.db.models.fields.TextField', [], {'null': 'True'}),
+            'certificates_show_before_end': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'course_image_url': ('django.db.models.fields.TextField', [], {}),
+            'days_early_for_beta': ('django.db.models.fields.FloatField', [], {'null': 'True'}),
+            'display_name': ('django.db.models.fields.TextField', [], {'null': 'True'}),
+            'display_number_with_default': ('django.db.models.fields.TextField', [], {}),
+            'display_org_with_default': ('django.db.models.fields.TextField', [], {}),
+            'end': ('django.db.models.fields.DateTimeField', [], {'null': 'True'}),
+            'end_of_course_survey_url': ('django.db.models.fields.TextField', [], {'null': 'True'}),
+            'facebook_url': ('django.db.models.fields.TextField', [], {'null': 'True'}),
+            'has_any_active_web_certificate': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'id': ('xmodule_django.models.CourseKeyField', [], {'max_length': '255', 'primary_key': 'True', 'db_index': 'True'}),
+            'lowest_passing_grade': ('django.db.models.fields.DecimalField', [], {'max_digits': '5', 'decimal_places': '2'}),
+            'mobile_available': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'social_sharing_url': ('django.db.models.fields.TextField', [], {'null': 'True'}),
+            'start': ('django.db.models.fields.DateTimeField', [], {'null': 'True'}),
+            'visible_to_staff_only': ('django.db.models.fields.BooleanField', [], {'default': 'False'})
+        }
+    }
+
+    complete_apps = ['course_overviews']
\ No newline at end of file

openedx/core/djangoapps/content/course_overviews/models.py

@@ -10,6 +10,8 @@ from django.utils.translation import ugettext
 
 from util.date_utils import strftime_localized
 from xmodule import course_metadata_utils
+from xmodule.course_module import CourseDescriptor
+from xmodule.error_module import ErrorDescriptor
 from xmodule.modulestore.django import modulestore
 from xmodule_django.models import CourseKeyField, UsageKeyField
 
@@ -44,6 +46,7 @@ class CourseOverview(django.db.models.Model):
     # Certification data
     certificates_display_behavior = TextField(null=True)
     certificates_show_before_end = BooleanField()
+    cert_html_view_enabled = BooleanField()
     has_any_active_web_certificate = BooleanField()
     cert_name_short = TextField()
     cert_name_long = TextField()
@@ -91,6 +94,7 @@ class CourseOverview(django.db.models.Model):
 
             certificates_display_behavior=course.certificates_display_behavior,
             certificates_show_before_end=course.certificates_show_before_end,
+            cert_html_view_enabled=course.cert_html_view_enabled,
             has_any_active_web_certificate=(get_active_web_certificate(course) is not None),
             cert_name_short=course.cert_name_short,
             cert_name_long=course.cert_name_long,
@@ -114,10 +118,17 @@ class CourseOverview(django.db.models.Model):
         future use.
 
         Arguments:
-            course_id (CourseKey): the ID of the course overview to be loaded
+            course_id (CourseKey): the ID of the course overview to be loaded.
 
         Returns:
-            CourseOverview: overview of the requested course
+            CourseOverview: overview of the requested course. If loading course
+            from the module store failed, returns None.
+
+        Raises:
+            - CourseOverview.DoesNotExist if the course specified by course_id
+                was not found.
+            - IOError if some other error occurs while trying to load the
+                course from the module store.
         """
         course_overview = None
         try:
@@ -126,9 +137,17 @@ class CourseOverview(django.db.models.Model):
             store = modulestore()
             with store.bulk_operations(course_id):
                 course = store.get_course(course_id)
-                if course:
+                if isinstance(course, CourseDescriptor):
                     course_overview = CourseOverview._create_from_course(course)
-                    course_overview.save()  # Save new overview to the cache
+                    course_overview.save()
+                elif course is not None:
+                    raise IOError(
+                        "Error while loading course {} from the module store: {}",
+                        unicode(course_id),
+                        course.error_msg if isinstance(course, ErrorDescriptor) else unicode(course)
+                    )
+                else:
+                    raise CourseOverview.DoesNotExist()
         return course_overview
 
     def clean_id(self, padding_char='='):

openedx/core/djangoapps/content/course_overviews/tests.py

@@ -6,13 +6,16 @@ import ddt
 import itertools
 import pytz
 import math
+import mock
 
 from django.utils import timezone
 
 from lms.djangoapps.certificates.api import get_active_web_certificate
 from lms.djangoapps.courseware.courses import course_image_url
 from xmodule.course_metadata_utils import DEFAULT_START_DATE
+from xmodule.error_module import ErrorDescriptor
 from xmodule.modulestore import ModuleStoreEnum
+from xmodule.modulestore.django import modulestore
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
 from xmodule.modulestore.tests.factories import CourseFactory, check_mongo_calls, check_mongo_calls_range
 
@@ -41,12 +44,18 @@ class CourseOverviewTestCase(ModuleStoreTestCase):
          - the CourseDescriptor itself
          - a CourseOverview that was newly constructed from _create_from_course
          - a CourseOverview that was loaded from the MySQL database
+
+        Arguments:
+            course (CourseDescriptor): the course to be checked.
         """
 
         def get_seconds_since_epoch(date_time):
             """
             Returns the number of seconds between the Unix Epoch and the given
                 datetime. If the given datetime is None, return None.
+
+            Arguments:
+                date_time (datetime): the datetime in question.
             """
             if date_time is None:
                 return None
@@ -189,18 +198,14 @@ class CourseOverviewTestCase(ModuleStoreTestCase):
         by comparing pairs of them given a variety of scenarios.
 
         Arguments:
-            course_kwargs (dict): kwargs to be passed to course constructor
-            modulestore_type (ModuleStoreEnum.Type)
-            is_user_enrolled (bool)
+            course_kwargs (dict): kwargs to be passed to course constructor.
+            modulestore_type (ModuleStoreEnum.Type): type of store to create the
+                course in.
         """
-
-        course = CourseFactory.create(
-            course="TEST101",
-            org="edX",
-            run="Run1",
-            default_store=modulestore_type,
-            **course_kwargs
-        )
+        # Note: We specify a value for 'run' here because, for some reason,
+        # .create raises an InvalidKeyError if we don't (even though my
+        # other test functions don't specify a run but work fine).
+        course = CourseFactory.create(default_store=modulestore_type, run="TestRun", **course_kwargs)
         self.check_course_overview_against_course(course)
 
     @ddt.data(ModuleStoreEnum.Type.mongo, ModuleStoreEnum.Type.split)
@@ -208,17 +213,15 @@ class CourseOverviewTestCase(ModuleStoreTestCase):
         """
         Tests that when a course is published, the corresponding
         course_overview is removed from the cache.
+
+        Arguments:
+            modulestore_type (ModuleStoreEnum.Type): type of store to create the
+                course in.
         """
         with self.store.default_store(modulestore_type):
 
             # Create a course where mobile_available is True.
-            course = CourseFactory.create(
-                course="TEST101",
-                org="edX",
-                run="Run1",
-                mobile_available=True,
-                default_store=modulestore_type
-            )
+            course = CourseFactory.create(mobile_available=True, default_store=modulestore_type)
             course_overview_1 = CourseOverview.get_from_id(course.id)
             self.assertTrue(course_overview_1.mobile_available)
 
@@ -238,14 +241,16 @@ class CourseOverviewTestCase(ModuleStoreTestCase):
     def test_course_overview_caching(self, modulestore_type, min_mongo_calls, max_mongo_calls):
         """
         Tests that CourseOverview structures are actually getting cached.
+
+        Arguments:
+            modulestore_type (ModuleStoreEnum.Type): type of store to create the
+                course in.
+            min_mongo_calls (int): minimum number of MongoDB queries we expect
+                to be made.
+            max_mongo_calls (int): maximum number of MongoDB queries we expect
+                to be made.
         """
-        course = CourseFactory.create(
-            course="TEST101",
-            org="edX",
-            run="Run1",
-            mobile_available=True,
-            default_store=modulestore_type
-        )
+        course = CourseFactory.create(default_store=modulestore_type)
 
         # The first time we load a CourseOverview, it will be a cache miss, so
         # we expect the modulestore to be queried.
@@ -256,3 +261,36 @@ class CourseOverviewTestCase(ModuleStoreTestCase):
         # we expect no modulestore queries to be made.
         with check_mongo_calls(0):
             _course_overview_2 = CourseOverview.get_from_id(course.id)
+
+    @ddt.data(ModuleStoreEnum.Type.split, ModuleStoreEnum.Type.mongo)
+    def test_get_non_existent_course(self, modulestore_type):
+        """
+        Tests that requesting a non-existent course from get_from_id raises
+        CourseOverview.DoesNotExist.
+
+        Arguments:
+            modulestore_type (ModuleStoreEnum.Type): type of store to create the
+                course in.
+        """
+        store = modulestore()._get_modulestore_by_type(modulestore_type)  # pylint: disable=protected-access
+        with self.assertRaises(CourseOverview.DoesNotExist):
+            CourseOverview.get_from_id(store.make_course_key('Non', 'Existent', 'Course'))
+
+    @ddt.data(ModuleStoreEnum.Type.split, ModuleStoreEnum.Type.mongo)
+    def test_get_errored_course(self, modulestore_type):
+        """
+        Test that getting an ErrorDescriptor back from the module store causes
+        get_from_id to raise an IOError.
+
+        Arguments:
+            modulestore_type (ModuleStoreEnum.Type): type of store to create the
+                course in.
+        """
+        course = CourseFactory.create(default_store=modulestore_type)
+        mock_get_course = mock.Mock(return_value=ErrorDescriptor)
+        with mock.patch('xmodule.modulestore.mixed.MixedModuleStore.get_course', mock_get_course):
+            # This mock makes it so when the module store tries to load course data,
+            # an exception is thrown, which causes get_course to return an ErrorDescriptor,
+            # which causes get_from_id to raise an IOError.
+            with self.assertRaises(IOError):
+                CourseOverview.get_from_id(course.id)