feat: limit the number of resulting learners in Django admin manage l…

…earners view

...so that we can support customers with a very large number of learners
ENT-8850

CHANGELOG.rst

@@ -15,6 +15,12 @@ Change Log
 
 Unreleased
 ----------
+* nothing unreleased
+
+[4.17.0]
+--------
+* feat: limit the number of resulting learners in Django admin manage learners view
+
 [4.16.5]
 --------
 * feat: splitting out group membership serializer learner id into lms user ID and ecu ID

enterprise/__init__.py

@@ -2,4 +2,4 @@
 Your project description goes here.
 """
 
-__version__ = "4.16.5"
+__version__ = "4.17.0"

enterprise/admin/views.py

@@ -37,7 +37,7 @@
 from enterprise.api_client.discovery import get_course_catalog_api_service_client
 from enterprise.api_client.ecommerce import EcommerceApiClient
 from enterprise.api_client.sso_orchestrator import EnterpriseSSOOrchestratorApiClient, SsoOrchestratorClientError
-from enterprise.constants import PAGE_SIZE
+from enterprise.constants import DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT, PAGE_SIZE
 from enterprise.errors import LinkUserToEnterpriseError
 from enterprise.models import (
     EnrollmentNotificationEmailTemplate,
@@ -357,7 +357,11 @@ def get_search_keyword(self, request):
 
     def get_enterprise_customer_user_queryset(self, request, search_keyword, customer_uuid, page_size=PAGE_SIZE):
         """
-        Get the list of EnterpriseCustomerUsers we want to render.
+        Get the list of EnterpriseCustomerUsers we want to render. Note that,
+        if no ``search_keyword`` is provided, the resulting queryset will
+        only include up to some constant limit of results, so that we
+        can support searching for particular user records in customers
+        with very large numbers of learners.
 
         Arguments:
             request (HttpRequest): HTTP Request instance.
@@ -367,16 +371,29 @@ def get_enterprise_customer_user_queryset(self, request, search_keyword, custome
             page_size (int): Number of learners displayed in each paginated set.
         """
         page = request.GET.get('page', 1)
-        learners = EnterpriseCustomerUser.objects.filter(enterprise_customer__uuid=customer_uuid)
-        user_ids = learners.values_list('user_id', flat=True)
-        matching_users = User.objects.filter(pk__in=user_ids)
-        if search_keyword is not None:
-            matching_users = matching_users.filter(
-                Q(email__icontains=search_keyword) | Q(username__icontains=search_keyword)
+        if search_keyword:
+            enterprise_learners = self._get_searched_enterprise_customer_users(
+                search_keyword,
+                customer_uuid,
             )
-        matching_user_ids = matching_users.values_list('pk', flat=True)
-        learners = learners.filter(user_id__in=matching_user_ids)
-        return paginated_list(learners, page, page_size)
+        else:
+            enterprise_learners = EnterpriseCustomerUser.objects.filter(
+                enterprise_customer__uuid=customer_uuid,
+            )[:DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT]
+        return paginated_list(enterprise_learners, page, page_size)
+
+    def _get_searched_enterprise_customer_users(self, search_keyword, customer_uuid):
+        """
+        Helper to return a (possibly truncated) queryset of enterprise customer users
+        who match some search criteria based on corresponding ``core.User`` records.
+        """
+        matching_user_ids = User.objects.filter(
+            Q(email__icontains=search_keyword) | Q(username__icontains=search_keyword)
+        ).values_list('id', flat=True)
+        return EnterpriseCustomerUser.objects.filter(
+            enterprise_customer__uuid=customer_uuid,
+            user_id__in=matching_user_ids,
+        )[:DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT]
 
     def get_pending_users_queryset(self, search_keyword, customer_uuid):
         """
@@ -387,14 +404,15 @@ def get_pending_users_queryset(self, search_keyword, customer_uuid):
             customer_uuid (str): A unique identifier to filter down to only pending users
             linked to a particular EnterpriseCustomer.
         """
-        queryset = PendingEnterpriseCustomerUser.objects.filter(
-            enterprise_customer__uuid=customer_uuid
-        )
-
-        if search_keyword is not None:
-            queryset = queryset.filter(user_email__icontains=search_keyword)
-
-        return queryset
+        if search_keyword:
+            return PendingEnterpriseCustomerUser.objects.filter(
+                enterprise_customer__uuid=customer_uuid,
+                user_email__icontains=search_keyword,
+            )[:DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT]
+        else:
+            return PendingEnterpriseCustomerUser.objects.filter(
+                enterprise_customer__uuid=customer_uuid
+            )[:DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT]
 
     @classmethod
     def _handle_singular(cls, request, enterprise_customer, manage_learners_form):

enterprise/constants.py

@@ -252,3 +252,6 @@ class FulfillmentTypes:
 )
 
 ENTITY_ID_REGEX = r"<(\w+:)?EntityDescriptor.*?entityID=['\"](.*?)['\"].*?>"
+
+# Max learners included in the Admin Manage Learners page
+DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT = 10000

tests/test_admin/test_view.py

@@ -584,6 +584,39 @@ def test_get_existing_links_only(self):
         response = self.client.get(self.view_url)
         self._test_get_response(response, linked_learners, [])
 
+    def test_users_limit_enforced(self):
+        """
+        Tests that we only return/render up to a constant limit
+        of enterprise customer user records, both pending and "concrete".
+        """
+        self._login()
+
+        _ = [
+            EnterpriseCustomerUserFactory(
+                enterprise_customer=self.enterprise_customer,
+                user_id=UserFactory().id,
+            ),
+            EnterpriseCustomerUserFactory(
+                enterprise_customer=self.enterprise_customer,
+                user_id=UserFactory().id,
+            ),
+            EnterpriseCustomerUserFactory(
+                enterprise_customer=self.enterprise_customer,
+                user_id=UserFactory().id,
+            ),
+        ]
+        _ = [
+            PendingEnterpriseCustomerUserFactory(enterprise_customer=self.enterprise_customer),
+            PendingEnterpriseCustomerUserFactory(enterprise_customer=self.enterprise_customer),
+            PendingEnterpriseCustomerUserFactory(enterprise_customer=self.enterprise_customer),
+        ]
+        with mock.patch('enterprise.admin.views.DJANGO_ADMIN_MANAGE_LEARNERS_LIMIT', 2):
+            response = self.client.get(self.view_url)
+
+        assert response.status_code == 200
+        assert len(list(response.context[self.context_parameters.LEARNERS])) == 2
+        assert len(list(response.context[self.context_parameters.PENDING_LEARNERS])) == 2
+
     def test_get_existing_and_pending_links(self):
         self._login()