fix: sync enterprise customer default language changes to braze

CHANGELOG.rst

@@ -17,6 +17,10 @@ Unreleased
 ----------
 * nothing unreleased
 
+[6.6.3] - 2026-01-26
+---------------------
+* fix: sync enterprise customer default language changes to braze
+
 [6.6.2] - 2026-01-15
 ---------------------
 * feat: add a waffle flag for invite admins

enterprise/__init__.py

@@ -2,4 +2,4 @@
 Your project description goes here.
 """
 
-__version__ = "6.6.2"
+__version__ = "6.6.3"

enterprise/signals.py

@@ -13,7 +13,7 @@
 from enterprise.api import activate_admin_permissions
 from enterprise.api_client.enterprise_catalog import EnterpriseCatalogApiClient
 from enterprise.decorators import disable_for_loaddata
-from enterprise.tasks import create_enterprise_enrollment
+from enterprise.tasks import create_enterprise_enrollment, track_enterprise_language_update_for_all_learners
 from enterprise.utils import (
     NotConnectedToOpenEdX,
     get_default_catalog_content_filter,
@@ -117,6 +117,47 @@ def update_lang_pref_of_all_learners(sender, instance, **kwargs):  # pylint: dis
             unset_language_of_all_enterprise_learners(instance)
 
 
+@receiver(pre_save, sender=models.EnterpriseCustomer)
+def track_default_language_change_in_braze(sender, instance, **kwargs):  # pylint: disable=unused-argument
+    """
+    Track default_language changes in Braze when EnterpriseCustomer is saved.
+
+    Triggers a Celery task to sync the default_language to Braze for all active learners when:
+    - A new customer is created with default_language set
+    - An existing customer's default_language is changed (including to/from None)
+
+    Args:
+        sender: The model class (EnterpriseCustomer)
+        instance: The actual instance being saved
+    """
+    # Get the previous state from database
+    prev_state = models.EnterpriseCustomer.objects.filter(uuid=instance.uuid).first()
+    old_language = prev_state.default_language if prev_state else None
+    new_language = instance.default_language
+
+    # Check if default_language actually changed
+    if old_language == new_language:
+        return
+
+    # Skip if this is a new customer being created with no language set
+    if prev_state is None and new_language is None:
+        return
+
+    # Language changed - trigger Braze sync
+    logger.info(
+        "Default language changed for EnterpriseCustomer %s (%s) from '%s' to '%s'. "
+        "Triggering Braze update task.",
+        instance.name,
+        instance.uuid,
+        old_language,
+        new_language
+    )
+    track_enterprise_language_update_for_all_learners.delay(
+        str(instance.uuid),
+        new_language
+    )
+
+
 @receiver(pre_save, sender=models.EnterpriseCustomerBrandingConfiguration)
 def skip_saving_logo_file(sender, instance, **kwargs):     # pylint: disable=unused-argument
     """

enterprise/tasks.py

@@ -16,7 +16,13 @@
 from enterprise.api_client.braze import ENTERPRISE_BRAZE_ALIAS_LABEL, MAX_NUM_IDENTIFY_USERS_ALIASES, BrazeAPIClient
 from enterprise.api_client.enterprise_catalog import EnterpriseCatalogApiClient
 from enterprise.constants import SSO_BRAZE_CAMPAIGN_ID
-from enterprise.utils import batch_dict, get_enterprise_customer, localized_utcnow, send_email_notification_message
+from enterprise.utils import (
+    batch,
+    batch_dict,
+    get_enterprise_customer,
+    localized_utcnow,
+    send_email_notification_message,
+)
 
 LOGGER = getLogger(__name__)
 
@@ -436,3 +442,82 @@ def send_group_membership_removal_notification(enterprise_customer_uuid, members
             errored_at=localized_utcnow())
         LOGGER.exception(message)
         raise exc
+
+
+@shared_task
+@set_code_owner_attribute
+def track_enterprise_language_update_for_all_learners(enterprise_customer_uuid, new_language):
+    """
+    Update language preference in Braze for all active learners of an enterprise customer.
+
+    Uses Braze's batch track_users endpoint which accepts up to 75 attribute objects per request.
+    Rate limit: 3,000 requests per 3 seconds.
+
+    Arguments:
+        enterprise_customer_uuid (str): UUID of the enterprise customer
+        new_language (str|None): The new default language code (e.g., 'en', 'es', 'fr') or None to clear
+    """
+
+    try:
+        enterprise_customer = get_enterprise_customer(enterprise_customer_uuid)
+        braze_client = BrazeAPIClient()
+
+        # Get all active, linked enterprise customer users
+        active_users = enterprise_customer.enterprise_customer_users.filter(
+            active=True,
+            linked=True
+        ).values_list('user_id', flat=True)
+
+        user_count = active_users.count()
+        LOGGER.info(
+            f"Tracking language update to '{new_language}' for {user_count} users "
+            f"in enterprise {enterprise_customer.name} ({enterprise_customer_uuid})"
+        )
+
+        if user_count == 0:
+            LOGGER.info(
+                f"No active users found for enterprise {enterprise_customer.name}. Skipping Braze sync."
+            )
+            return
+
+        # Braze allows 75 attribute objects per request
+        BATCH_SIZE = 75
+        success_count = 0
+        error_count = 0
+
+        # Process users in batches using the batch utility
+        for user_id_batch in batch(active_users, BATCH_SIZE):
+            # Build attributes array for this batch
+            # Each item is an attribute object with external_id and pref-lang
+            attributes = [
+                {
+                    'external_id': str(user_id),
+                    'pref-lang': new_language
+                }
+                for user_id in user_id_batch
+            ]
+
+            try:
+                # Call Braze track_users with batch of attributes
+                braze_client.track_user(attributes=attributes)
+                success_count += len(user_id_batch)
+                LOGGER.info(
+                    f"Successfully tracked language for batch of {len(user_id_batch)} users "
+                    f"(processed {success_count}/{user_count})"
+                )
+            except Exception as exc:
+                error_count += len(user_id_batch)
+                LOGGER.warning(
+                    f"Failed to track language for batch of {len(user_id_batch)} users: {str(exc)}"
+                )
+
+        LOGGER.info(
+            f"Language update tracking complete for enterprise {enterprise_customer.name}. "
+            f"Success: {success_count}, Errors: {error_count}"
+        )
+
+    except Exception as exc:
+        LOGGER.exception(
+            f"Failed to track language update for enterprise {enterprise_customer_uuid}: {str(exc)}"
+        )
+        raise

tests/test_enterprise/test_signals.py

@@ -1174,3 +1174,113 @@ def test_update_enterprise_catalog_query(self, api_client_mock):
             include_exec_ed_2u_courses=test_query.include_exec_ed_2u_courses,
         )
         api_client_mock.return_value.refresh_catalogs.assert_called_with([enterprise_catalog_2])
+
+
+@mark.django_db
+@ddt.ddt
+class TestTrackDefaultLanguageChangeInBraze(unittest.TestCase):
+    """
+    Tests for track_default_language_change_in_braze signal handler.
+    """
+
+    def setUp(self):
+        """
+        Setup for test.
+        """
+        self.enterprise_customer = EnterpriseCustomerFactory(
+            name='Test Enterprise',
+            default_language=None,
+        )
+        super().setUp()
+
+    @ddt.data(
+        (None, 'en'),  # Setting language from None
+        ('en', 'es'),  # Changing from one language to another
+        ('en', None),  # Clearing language back to None
+    )
+    @ddt.unpack
+    @mock.patch('enterprise.signals.track_enterprise_language_update_for_all_learners')
+    def test_signal_triggers_on_language_change(self, initial_language, new_language, mock_task):
+        """
+        Verify signal triggers Celery task when default_language changes.
+        Tests: None→language, language→language, language→None transitions.
+        """
+        # Set initial language if needed
+        if initial_language is not None:
+            self.enterprise_customer.default_language = initial_language
+            self.enterprise_customer.save()
+            mock_task.delay.reset_mock()
+
+        # Change to new language
+        self.enterprise_customer.default_language = new_language
+        self.enterprise_customer.save()
+
+        # Verify task was called with new language
+        mock_task.delay.assert_called_once_with(
+            str(self.enterprise_customer.uuid),
+            new_language
+        )
+
+    @mock.patch('enterprise.signals.track_enterprise_language_update_for_all_learners')
+    def test_signal_does_not_trigger_when_language_unchanged(self, mock_task):
+        """
+        Verify signal does not trigger when default_language is unchanged.
+        """
+        # Set initial language
+        self.enterprise_customer.default_language = 'en'
+        self.enterprise_customer.save()
+        mock_task.delay.reset_mock()
+
+        # Save without changing language
+        self.enterprise_customer.name = 'Updated Name'
+        self.enterprise_customer.save()
+
+        # Verify task was not called
+        mock_task.delay.assert_not_called()
+
+    @mock.patch('enterprise.signals.track_enterprise_language_update_for_all_learners')
+    def test_signal_does_not_trigger_on_new_customer_with_no_language(self, mock_task):
+        """
+        Verify signal does not trigger when creating new customer with no language.
+        """
+        # Create new customer with no default_language
+        new_customer = EnterpriseCustomerFactory(
+            name='New Customer',
+            default_language=None,
+        )
+
+        # Verify task was not called
+        mock_task.delay.assert_not_called()
+
+    @mock.patch('enterprise.signals.track_enterprise_language_update_for_all_learners')
+    def test_signal_triggers_on_new_customer_with_language(self, mock_task):
+        """
+        Verify signal triggers when creating new customer with default_language set.
+        """
+        # Create new customer with default_language
+        new_customer = EnterpriseCustomerFactory(
+            name='New Customer',
+            default_language='fr',
+        )
+
+        # Verify task was called
+        mock_task.delay.assert_called_once_with(
+            str(new_customer.uuid),
+            'fr'
+        )
+
+    @mock.patch('enterprise.signals.track_enterprise_language_update_for_all_learners')
+    def test_signal_logs_language_change(self, mock_task):
+        """
+        Verify signal logs the language change appropriately.
+        """
+        with self.assertLogs('enterprise.signals', level='INFO') as logs:
+            self.enterprise_customer.default_language = 'de'
+            self.enterprise_customer.save()
+
+        # Verify log message contains expected information
+        log_output = ' '.join(logs.output)
+        assert 'Default language changed' in log_output
+        assert str(self.enterprise_customer.uuid) in log_output
+        assert 'None' in log_output  # old value
+        assert 'de' in log_output  # new value