From c5e90464e996eb2c156d501616d380b4ff5ba3cf Mon Sep 17 00:00:00 2001
From: Jillian Vogel <jill@opencraft.com>
Date: Thu, 26 Jul 2018 11:11:17 +0930
Subject: [PATCH] Address PR review:

* uses openedx waffle_utils instead of straight waffle
* adds student.STUDENT_WAFFLE_NAMESPACE
* improves comment

Also changed the waffle switch to use _ instead of . to respect current conventions.
---
 common/djangoapps/student/__init__.py           |  8 ++++++++
 common/djangoapps/student/admin.py              | 17 +++++++++--------
 .../student/tests/test_admin_views.py           | 10 ++++------
 3 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/common/djangoapps/student/__init__.py b/common/djangoapps/student/__init__.py
index e69de29bb2..a77f14c551 100644
--- a/common/djangoapps/student/__init__.py
+++ b/common/djangoapps/student/__init__.py
@@ -0,0 +1,8 @@
+"""
+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')
diff --git a/common/djangoapps/student/admin.py b/common/djangoapps/student/admin.py
index ae2d63c0ae..9446a02249 100644
--- a/common/djangoapps/student/admin.py
+++ b/common/djangoapps/student/admin.py
@@ -1,6 +1,5 @@
 """ Django admin pages for student app """
 from config_models.admin import ConfigurationModelAdmin
-import waffle
 from django import forms
 from django.contrib import admin
 from django.contrib.admin.sites import NotRegistered
@@ -10,7 +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,
@@ -29,6 +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."""
@@ -180,14 +186,9 @@ class CourseEnrollmentAdmin(admin.ModelAdmin):
 
     def has_permission(self, request, method):
         """
-        Returns True if the given method is allowed.
-
-        Access to these admin views is restricted because it makes DB quries that impact performance enough to cause a
-        site outage, cf https://openedx.atlassian.net/browse/OPS-2943
-
-        Enable these views using the waffle switch: `student.coursenrollment.admin`
+        Returns True if the given admin method is allowed.
         """
-        if waffle.switch_is_active('student.coursenrollment.admin'):
+        if COURSE_ENROLLMENT_ADMIN_SWITCH.is_enabled():
             return getattr(super(CourseEnrollmentAdmin, self), method)(request)
         return False
 
diff --git a/common/djangoapps/student/tests/test_admin_views.py b/common/djangoapps/student/tests/test_admin_views.py
index 7189f6f71e..641d934397 100644
--- a/common/djangoapps/student/tests/test_admin_views.py
+++ b/common/djangoapps/student/tests/test_admin_views.py
@@ -2,14 +2,13 @@
 Tests student admin.py
 """
 import ddt
-from waffle.testutils import override_switch
 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.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
@@ -224,13 +223,12 @@ class CourseEnrollmentAdminTest(SharedModuleStoreTestCase):
         response = getattr(self.client, method)(url)
         self.assertEqual(response.status_code, 403)
 
-    @override_switch('student.coursenrollment.admin', active=True)
     @ddt.data(*ADMIN_URLS)
     @ddt.unpack
     def test_view_enabled(self, method, url):
         """
-        Ensure CourseEnrollmentAdmin views can be enabled with the waffle flag.
+        Ensure CourseEnrollmentAdmin views can be enabled with the waffle switch.
         """
-        self.client.login(username=self.user.username, password='test')
-        response = getattr(self.client, method)(url)
+        with COURSE_ENROLLMENT_ADMIN_SWITCH.override(active=True):
+            response = getattr(self.client, method)(url)
         self.assertEqual(response.status_code, 200)