feat: Learner Home experimental rollout (#31642)

* feat: add experimental redirect for Learner Home

As a request by Data, this system repeatably groups users into
experiment groups. Based on end of user ID, users that fall beneath a
threshold (LEARNER_HOME_MFE_REDIRECT_PERCENTAGE) will be redirected to
the Learner Home experience, if enabled. Otherwise, learners will see
the legacy dashboard.

* feat: add learner home redirect percentage setting

Adds LEARNER_HOME_MFE_REDIRECT_PERCENTAGE to common settings to avoid a
failed lookup. Can be overridden through config.

* refactor: change test to not leak implementation

common/djangoapps/student/tests/test_views.py

@@ -235,13 +235,14 @@ class StudentDashboardTests(SharedModuleStoreTestCase, MilestonesTestCaseMixin,
         response = self.client.get(self.path)
         self.assertRedirects(response, reverse('account_settings'))
 
-    def test_redirect_to_learner_home(self):
+    @patch('common.djangoapps.student.views.dashboard.should_redirect_to_learner_home_mfe')
+    def test_redirect_to_learner_home(self, mock_should_redirect_to_learner_home_mfe):
         """
         if learner home mfe is enabled, redirect to learner home mfe
         """
-        with patch('lms.djangoapps.learner_home.waffle.ENABLE_LEARNER_HOME_MFE.is_enabled', return_value=True):
-            response = self.client.get(self.path)
-            self.assertRedirects(response, settings.LEARNER_HOME_MICROFRONTEND_URL, fetch_redirect_response=False)
+        mock_should_redirect_to_learner_home_mfe.return_value = True
+        response = self.client.get(self.path)
+        self.assertRedirects(response, settings.LEARNER_HOME_MICROFRONTEND_URL, fetch_redirect_response=False)
 
     def test_course_cert_available_message_after_course_end(self):
         course_key = CourseKey.from_string('course-v1:edX+DemoX+Demo_Course')

common/djangoapps/student/views/dashboard.py

@@ -521,7 +521,7 @@ def student_dashboard(request):  # lint-amnesty, pylint: disable=too-many-statem
     if not UserProfile.objects.filter(user=user).exists():
         return redirect(reverse('account_settings'))
 
-    if should_redirect_to_learner_home_mfe():
+    if should_redirect_to_learner_home_mfe(user):
         return redirect(settings.LEARNER_HOME_MICROFRONTEND_URL)
 
     platform_name = configuration_helpers.get_value("platform_name", settings.PLATFORM_NAME)

lms/djangoapps/learner_home/test_waffle.py

@@ -0,0 +1,54 @@
+"""
+Tests for toggles, where there is logic beyond enable/disable.
+"""
+
+from unittest.mock import patch
+import ddt
+
+from django.test import override_settings
+
+from common.djangoapps.student.tests.factories import UserFactory
+from lms.djangoapps.learner_home.waffle import should_redirect_to_learner_home_mfe
+from xmodule.modulestore.tests.django_utils import SharedModuleStoreTestCase
+
+
+@ddt.ddt
+class TestLearnerHomeRedirect(SharedModuleStoreTestCase):
+    """
+    Tests for should_redirect_to_learner_home, used for experimental rollout.
+    """
+
+    def setUp(self):
+        super().setUp()
+
+        # Set up a user for testing
+        self.user = UserFactory
+
+    @patch("lms.djangoapps.learner_home.waffle.ENABLE_LEARNER_HOME_MFE")
+    def test_should_redirect_to_learner_home_disabled(self, mock_enable_learner_home):
+        # Given Learner Home MFE feature is not enabled
+        mock_enable_learner_home.is_enabled.return_value = False
+
+        # When I check if I should redirect
+        redirect_choice = should_redirect_to_learner_home_mfe(self.user)
+
+        # Then I never redirect
+        self.assertFalse(redirect_choice)
+
+    @ddt.data((0, True), (50, False), (100, True))
+    @ddt.unpack
+    @patch("lms.djangoapps.learner_home.waffle.ENABLE_LEARNER_HOME_MFE")
+    @override_settings(LEARNER_HOME_MFE_REDIRECT_PERCENTAGE=50)
+    def test_should_redirect_to_learner_home_enabled(
+        self, user_id, expect_redirect, mock_enable_learner_home
+    ):
+        # Given Learner Home MFE feature is enabled
+        mock_enable_learner_home.is_enabled.return_value = True
+        self.user.id = user_id
+
+        # When I check if I should redirect
+        redirect_choice = should_redirect_to_learner_home_mfe(self.user)
+
+        # Then I redirect based on configuration
+        # (currently user ID % 100 < redirect percentage)
+        self.assertEqual(expect_redirect, redirect_choice)

lms/djangoapps/learner_home/waffle.py

@@ -1,6 +1,7 @@
 """
 Configuration for features of Learner Home
 """
+from django.conf import settings
 
 from edx_toggles.toggles import WaffleFlag
 
@@ -22,7 +23,25 @@ ENABLE_LEARNER_HOME_MFE = WaffleFlag(
 )
 
 
-def should_redirect_to_learner_home_mfe():
-    return configuration_helpers.get_value(
+def should_redirect_to_learner_home_mfe(user):
+    """
+    Redirect a percentage of learners to Learner Home for experimentation.
+
+    Percentage is based on the LEARNER_HOME_MFE_REDIRECT_PERCENTAGE setting.
+    """
+
+    is_learning_mfe_enabled = configuration_helpers.get_value(
         "ENABLE_LEARNER_HOME_MFE", ENABLE_LEARNER_HOME_MFE.is_enabled()
     )
+
+    learning_mfe_redirect_percent = configuration_helpers.get_value(
+        "LEARNER_HOME_MFE_REDIRECT_PERCENTAGE",
+        settings.LEARNER_HOME_MFE_REDIRECT_PERCENTAGE,
+    )
+
+    # Redirect when 1) Learner Home MFE is enabled and 2) a user falls into the
+    # target range for experimental rollout.
+    if is_learning_mfe_enabled and user.id % 100 < learning_mfe_redirect_percent:
+        return True
+
+    return False

lms/envs/common.py

@@ -4976,6 +4976,8 @@ HIBP_LOGIN_BLOCK_PASSWORD_FREQUENCY_THRESHOLD = 5
 # .. toggle_tickets: https://openedx.atlassian.net/browse/VAN-838
 ENABLE_DYNAMIC_REGISTRATION_FIELDS = False
 
+LEARNER_HOME_MFE_REDIRECT_PERCENTAGE = 0
+
 ############### Settings for the ace_common plugin #################
 # Note that all settings are actually defined by the plugin
 # pylint: disable=wrong-import-position