Merge pull request #18638 from open-craft/jill/reinstate-enrollments-admin

Gate access to the CourseEnrollmentAdmin view with a waffle switch

common/djangoapps/student/__init__.py

+"""
+Student app helpers and settings
+"""
+from openedx.core.djangoapps.waffle_utils import WaffleSwitchNamespace
+
+
+# Namespace for student app waffle switches
+STUDENT_WAFFLE_NAMESPACE = WaffleSwitchNamespace(name='student')

common/djangoapps/student/admin.py

@@ -9,7 +9,9 @@ from django.utils.translation import ugettext_lazy as _
 from opaque_keys import InvalidKeyError
 from opaque_keys.edx.keys import CourseKey
 
+from openedx.core.djangoapps.waffle_utils import WaffleSwitch
 from openedx.core.lib.courses import clean_course_id
+from student import STUDENT_WAFFLE_NAMESPACE
 from student.models import (
     CourseAccessRole,
     CourseEnrollment,
@@ -28,6 +30,11 @@ from xmodule.modulestore.django import modulestore
 
 User = get_user_model()  # pylint:disable=invalid-name
 
+# This switch exists because the CourseEnrollment admin views make DB queries that impact performance.
+# In a large enough deployment of Open edX, this is enough to cause a site outage.
+# See https://openedx.atlassian.net/browse/OPS-2943
+COURSE_ENROLLMENT_ADMIN_SWITCH = WaffleSwitch(STUDENT_WAFFLE_NAMESPACE, 'courseenrollment_admin')
+
 
 class CourseAccessRoleForm(forms.ModelForm):
     """Form for adding new Course Access Roles view the Django Admin Panel."""
@@ -165,13 +172,7 @@ class CourseEnrollmentForm(forms.ModelForm):
         fields = '__all__'
 
 
-# Page disabled because it makes DB quries that impact performance enough to
-# cause a site outage. It may be re-enabled when it is updated to make more
-# efficent DB queries
-# https://openedx.atlassian.net/browse/OPS-2943
-# Learner ticket to add functionality to /support
-# https://openedx.atlassian.net/browse/LEARNER-4744
-#@admin.register(CourseEnrollment)
+@admin.register(CourseEnrollment)
 class CourseEnrollmentAdmin(admin.ModelAdmin):
     """ Admin interface for the CourseEnrollment model. """
     list_display = ('id', 'course_id', 'mode', 'user', 'is_active',)
@@ -183,6 +184,38 @@ class CourseEnrollmentAdmin(admin.ModelAdmin):
     def queryset(self, request):
         return super(CourseEnrollmentAdmin, self).queryset(request).select_related('user')
 
+    def has_permission(self, request, method):
+        """
+        Returns True if the given admin method is allowed.
+        """
+        if COURSE_ENROLLMENT_ADMIN_SWITCH.is_enabled():
+            return getattr(super(CourseEnrollmentAdmin, self), method)(request)
+        return False
+
+    def has_add_permission(self, request):
+        """
+        Returns True if CourseEnrollment objects can be added via the admin view.
+        """
+        return self.has_permission(request, 'has_add_permission')
+
+    def has_change_permission(self, request, obj=None):
+        """
+        Returns True if CourseEnrollment objects can be modified via the admin view.
+        """
+        return self.has_permission(request, 'has_change_permission')
+
+    def has_delete_permission(self, request, obj=None):
+        """
+        Returns True if CourseEnrollment objects can be deleted via the admin view.
+        """
+        return self.has_permission(request, 'has_delete_permission')
+
+    def has_module_permission(self, request):
+        """
+        Returns True if links to the CourseEnrollment admin view can be displayed.
+        """
+        return self.has_permission(request, 'has_module_permission')
+
 
 class UserProfileInline(admin.StackedInline):
     """ Inline admin interface for UserProfile model. """

common/djangoapps/student/tests/test_admin_views.py

 """
 Tests student admin.py
 """
+import ddt
 from django.contrib.admin.sites import AdminSite
 from django.contrib.auth.models import User
 from django.urls import reverse
 from django.test import TestCase
 from mock import Mock
 
-from student.admin import UserAdmin
-from student.tests.factories import UserFactory
+from student.admin import COURSE_ENROLLMENT_ADMIN_SWITCH, UserAdmin
+from student.tests.factories import CourseEnrollmentFactory, UserFactory
 from xmodule.modulestore.tests.django_utils import SharedModuleStoreTestCase
 from xmodule.modulestore.tests.factories import CourseFactory
 
@@ -186,3 +187,48 @@ class AdminUserPageTest(TestCase):
         request = Mock()
         user = Mock()
         self.assertIn('username', self.admin.get_readonly_fields(request, user))
+
+
+@ddt.ddt
+class CourseEnrollmentAdminTest(SharedModuleStoreTestCase):
+    """
+    Unit tests for the CourseEnrollmentAdmin view.
+    """
+    ADMIN_URLS = (
+        ('get', reverse('admin:student_courseenrollment_add')),
+        ('get', reverse('admin:student_courseenrollment_changelist')),
+        ('get', reverse('admin:student_courseenrollment_change', args=(1,))),
+        ('get', reverse('admin:student_courseenrollment_delete', args=(1,))),
+        ('post', reverse('admin:student_courseenrollment_add')),
+        ('post', reverse('admin:student_courseenrollment_changelist')),
+        ('post', reverse('admin:student_courseenrollment_change', args=(1,))),
+        ('post', reverse('admin:student_courseenrollment_delete', args=(1,))),
+    )
+
+    def setUp(self):
+        super(CourseEnrollmentAdminTest, self).setUp()
+        self.user = UserFactory.create(is_staff=True, is_superuser=True)
+        self.client.login(username=self.user.username, password='test')
+        CourseEnrollmentFactory(
+            user=self.user,
+            course_id=CourseFactory().id,  # pylint: disable=no-member
+        )
+
+    @ddt.data(*ADMIN_URLS)
+    @ddt.unpack
+    def test_view_disabled(self, method, url):
+        """
+        All CourseEnrollmentAdmin views are disabled by default.
+        """
+        response = getattr(self.client, method)(url)
+        self.assertEqual(response.status_code, 403)
+
+    @ddt.data(*ADMIN_URLS)
+    @ddt.unpack
+    def test_view_enabled(self, method, url):
+        """
+        Ensure CourseEnrollmentAdmin views can be enabled with the waffle switch.
+        """
+        with COURSE_ENROLLMENT_ADMIN_SWITCH.override(active=True):
+            response = getattr(self.client, method)(url)
+        self.assertEqual(response.status_code, 200)