Release 1.165.3

RELEASE.rst

@@ -1,6 +1,12 @@
 Release Notes
 =============
 
+Version 1.165.3
+---------------
+
+- Optimize course API pagination query (#3939)
+- ENABLE_MULTIPLE_CART_ITEMS=False should disable multi-product baskets even through APIs   (#3909)
+
 Version 1.165.2
 ---------------
 

courses/serializers/v2/courses.py

@@ -167,8 +167,8 @@ def get_certificate_available(self, instance) -> bool:
 
         return (
             instance.first_unexpired_run is not None
-            and hasattr(instance, "verified_courserun_count")
-            and instance.verified_courserun_count > 0
+            and hasattr(instance, "has_verified_courserun")
+            and instance.has_verified_courserun
             and not instance.certificates_disabled
             and has_live_certificate_page(instance)
         )

courses/serializers/v2/courses_test.py

@@ -84,12 +84,12 @@ def test_serialize_course(
         run=courseRun1, **({} if is_anonymous else {"user": user})
     )
 
-    # Fake out a "verified_courserun_count" attribute - this is an annotation that the
+    # Fake out a "has_verified_courserun" attribute - this is an annotation that the
     # viewset adds, but won't be here because we're just passing it in a straight
     # Course object.
-    course.verified_courserun_count = course.courseruns.filter(
+    course.has_verified_courserun = course.courseruns.filter(
         enrollment_modes__mode_slug=EDX_ENROLLMENT_VERIFIED_MODE
-    ).count()
+    ).exists()
 
     data = CourseWithCourseRunsSerializer(instance=course, context=mock_context).data
 
@@ -138,9 +138,9 @@ def _course_eligible_for_certificate():
         EnrollmentModeFactory.create(mode_slug=EDX_ENROLLMENT_VERIFIED_MODE)
     )
     course = course_run.course
-    course.verified_courserun_count = course.courseruns.filter(
+    course.has_verified_courserun = course.courseruns.filter(
         enrollment_modes__mode_slug=EDX_ENROLLMENT_VERIFIED_MODE
-    ).count()
+    ).exists()
     return course
 
 

courses/utils.py

@@ -24,6 +24,18 @@
 log = logging.getLogger(__name__)
 
 
+def verified_courserun_exists():
+    """Build an Exists() annotation for whether a course has a verified run."""
+    from openedx.constants import EDX_ENROLLMENT_VERIFIED_MODE  # noqa: PLC0415
+
+    return Exists(
+        CourseRun.objects.filter(
+            course_id=OuterRef("pk"),
+            enrollment_modes__mode_slug=EDX_ENROLLMENT_VERIFIED_MODE,
+        )
+    )
+
+
 def live_certificate_page_exists():
     """
     Build an Exists() subquery annotation for whether a live CertificatePage

courses/views/internal/__init__.py

@@ -1,7 +1,7 @@
 """Internal-only views for courses."""
 
 from django.contrib.contenttypes.models import ContentType
-from django.db.models import Count, Prefetch, Q
+from django.db.models import Prefetch
 from prefetch import PrefetchOption
 from rest_framework import viewsets
 from rest_framework_api_key.permissions import HasAPIKey
@@ -13,10 +13,9 @@
 )
 from courses.permissions import IsEtlUser
 from courses.serializers.internal import IngestibleCourseWithCourseRunsSerializer
-from courses.utils import live_certificate_page_exists
+from courses.utils import live_certificate_page_exists, verified_courserun_exists
 from courses.views.utils import Pagination
 from ecommerce.models import Product
-from openedx.constants import EDX_ENROLLMENT_VERIFIED_MODE
 
 
 class IngestibleCourseViewSet(viewsets.ReadOnlyModelViewSet):
@@ -76,19 +75,8 @@ def get_queryset(self):
             dated_runs_prefetch,
         )
         queryset = queryset.annotate(
-            count_b2b_courseruns=Count("courseruns__b2b_contract__id")
-        )
-        queryset = queryset.annotate(count_courseruns=Count("courseruns"))
-        queryset = queryset.annotate(
-            verified_courserun_count=Count(
-                "courseruns__enrollment_modes",
-                filter=Q(
-                    courseruns__enrollment_modes__mode_slug=EDX_ENROLLMENT_VERIFIED_MODE
-                ),
-            )
-        )
-        queryset = queryset.annotate(
-            has_live_certificate_page=live_certificate_page_exists()
+            has_verified_courserun=verified_courserun_exists(),
+            has_live_certificate_page=live_certificate_page_exists(),
         )
         queryset = queryset.prefetch(
             PrefetchOption(

courses/views/v2/__init__.py

@@ -8,7 +8,7 @@
 import django_filters
 from django.conf import settings
 from django.contrib.contenttypes.models import ContentType
-from django.db.models import Count, Prefetch, Q
+from django.db.models import Prefetch, Q
 from django.http import JsonResponse
 from django.shortcuts import get_object_or_404
 from django_filters.rest_framework import DjangoFilterBackend
@@ -77,6 +77,7 @@
     get_program_certificate_by_enrollment,
     get_unenrollable_courses,
     live_certificate_page_exists,
+    verified_courserun_exists,
 )
 from ecommerce.api import create_verified_program_course_run_enrollment
 from ecommerce.models import Product
@@ -464,19 +465,8 @@ def get_queryset(self):
             "departments", "in_programs", course_runs_prefetch
         )
         queryset = queryset.annotate(
-            count_b2b_courseruns=Count("courseruns__b2b_contract__id")
-        )
-        queryset = queryset.annotate(count_courseruns=Count("courseruns"))
-        queryset = queryset.annotate(
-            verified_courserun_count=Count(
-                "courseruns__enrollment_modes",
-                filter=Q(
-                    courseruns__enrollment_modes__mode_slug=EDX_ENROLLMENT_VERIFIED_MODE
-                ),
-            )
-        )
-        queryset = queryset.annotate(
-            has_live_certificate_page=live_certificate_page_exists()
+            has_verified_courserun=verified_courserun_exists(),
+            has_live_certificate_page=live_certificate_page_exists(),
         )
         queryset = queryset.prefetch_related(
             Prefetch(

courses/views/v2/views_test.py

@@ -15,7 +15,7 @@
 from django.contrib.auth.models import AnonymousUser
 from django.contrib.contenttypes.models import ContentType
 from django.db import connection
-from django.db.models import Q
+from django.db.models import Exists, Q
 from django.test import RequestFactory
 from django.urls import reverse
 from faker import Faker
@@ -77,7 +77,7 @@
     num_queries_from_department,
     num_queries_from_programs,
 )
-from courses.views.v2 import Pagination, ProgramFilterSet
+from courses.views.v2 import CourseViewSet, Pagination, ProgramFilterSet
 from ecommerce.factories import OrderFactory, ProductFactory
 from ecommerce.models import OrderStatus, Product
 from main import features
@@ -259,6 +259,14 @@ def test_delete_program(
     assert resp.status_code == status.HTTP_405_METHOD_NOT_ALLOWED
 
 
+def test_course_queryset_avoids_courserun_aggregate_annotations():
+    """Course pagination should not aggregate over every related course run."""
+    annotations = CourseViewSet().get_queryset().query.annotations
+
+    assert isinstance(annotations["has_verified_courserun"], Exists)
+    assert {"count_b2b_courseruns", "count_courseruns"}.isdisjoint(annotations)
+
+
 @pytest.mark.skip_nplusone_check
 @pytest.mark.usefixtures("course_catalog_data")
 @pytest.mark.parametrize("course_catalog_course_count", [100], indirect=True)

drf_lint_baseline.json

@@ -16,7 +16,16 @@
   "courses/serializers/v1/programs.py:303:27:ORM001",
   "courses/serializers/v1/programs.py:318:16:ORM001",
   "courses/serializers/v1/programs.py:335:17:ORM001",
+  "courses/serializers/v2/courses.py:138:18:ORM004",
+  "courses/serializers/v2/courses.py:142:18:ORM003",
+  "courses/serializers/v2/courses.py:150:19:ORM004",
+  "courses/serializers/v2/courses.py:157:11:ORM003",
+  "courses/serializers/v2/courses.py:158:22:ORM003",
+  "courses/serializers/v2/courses.py:169:12:ORM003",
+  "courses/serializers/v2/courses.py:219:12:ORM007",
+  "courses/serializers/v2/courses.py:268:15:ORM004",
   "courses/serializers/v2/courses.py:276:17:ORM002",
+  "courses/serializers/v2/courses.py:297:19:ORM007",
   "courses/serializers/v2/departments.py:35:40:ORM002",
   "courses/serializers/v2/departments.py:49:42:ORM002",
   "courses/serializers/v2/programs.py:387:50:ORM002",

ecommerce/tests/test_multiple_cart_items.py

@@ -115,6 +115,96 @@ def test_basket_items_count_endpoint(self, user_drf_client, user):
         # Should return count of distinct items, not total quantity
         assert response.data == 2
 
+    @override_settings(ENABLE_MULTIPLE_CART_ITEMS=False)
+    def test_create_basket_from_product_single_item_mode_replaces(
+        self, user_drf_client, user
+    ):
+        """With flag disabled, create_basket_from_product replaces existing basket items"""
+        existing_product = ProductFactory.create()
+        new_product = ProductFactory.create()
+
+        basket = BasketFactory.create(user=user)
+        BasketItemFactory.create(basket=basket, product=existing_product)
+
+        assert basket.basket_items.count() == 1
+
+        response = user_drf_client.post(
+            f"/api/v0/baskets/create_from_product/{new_product.id}/",
+        )
+
+        assert response.status_code == status.HTTP_201_CREATED
+        basket.refresh_from_db()
+        assert basket.basket_items.count() == 1
+        assert basket.basket_items.first().product == new_product
+
+    @override_settings(ENABLE_MULTIPLE_CART_ITEMS=True)
+    def test_create_basket_from_product_multiple_items_mode_keeps_existing(
+        self, user_drf_client, user
+    ):
+        """With flag enabled, create_basket_from_product keeps existing basket items"""
+        existing_product = ProductFactory.create()
+        new_product = ProductFactory.create()
+
+        basket = BasketFactory.create(user=user)
+        BasketItemFactory.create(basket=basket, product=existing_product)
+
+        assert basket.basket_items.count() == 1
+
+        response = user_drf_client.post(
+            f"/api/v0/baskets/create_from_product/{new_product.id}/",
+        )
+
+        assert response.status_code == status.HTTP_201_CREATED
+        basket.refresh_from_db()
+        assert basket.basket_items.count() == 2
+
+    @override_settings(ENABLE_MULTIPLE_CART_ITEMS=False)
+    def test_create_basket_with_products_single_item_mode_replaces(
+        self, user_drf_client, user
+    ):
+        """With flag disabled, create_basket_with_products replaces existing basket items"""
+        existing_product = ProductFactory.create()
+        new_product = ProductFactory.create()
+
+        basket = BasketFactory.create(user=user)
+        BasketItemFactory.create(basket=basket, product=existing_product)
+
+        assert basket.basket_items.count() == 1
+
+        response = user_drf_client.post(
+            "/api/v0/baskets/create_with_products/",
+            data={"product_ids": [{"product_id": new_product.id, "quantity": 1}]},
+            format="json",
+        )
+
+        assert response.status_code == status.HTTP_200_OK
+        basket.refresh_from_db()
+        assert basket.basket_items.count() == 1
+        assert basket.basket_items.first().product == new_product
+
+    @override_settings(ENABLE_MULTIPLE_CART_ITEMS=False)
+    def test_create_basket_with_products_single_item_mode_rejects_multiple(
+        self,
+        user_drf_client,
+        user,  # noqa: ARG002
+    ):
+        """With flag disabled, create_basket_with_products rejects multiple products"""
+        product1 = ProductFactory.create()
+        product2 = ProductFactory.create()
+
+        response = user_drf_client.post(
+            "/api/v0/baskets/create_with_products/",
+            data={
+                "product_ids": [
+                    {"product_id": product1.id, "quantity": 1},
+                    {"product_id": product2.id, "quantity": 1},
+                ]
+            },
+            format="json",
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
     @override_settings(ENABLE_MULTIPLE_CART_ITEMS=False)
     def test_existing_basket_item_viewset_still_works(self, user_drf_client, user):
         """Test that the existing BasketItemViewSet still works regardless of feature flag"""

ecommerce/views/v0/__init__.py

@@ -5,6 +5,7 @@
 import logging
 
 import django_filters
+from django.conf import settings
 from django.contrib.auth import get_user_model
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.core.exceptions import ObjectDoesNotExist
@@ -244,6 +245,11 @@ def _create_basket_from_product(
     with transaction.atomic():
         basket = establish_basket_for_request(request, for_update=True)
 
+        if not getattr(settings, "ENABLE_MULTIPLE_CART_ITEMS", False):
+            basket.basket_items.all().delete()
+            # Don't clear discounts here — the read→delete→reapply logic below
+            # already preserves and re-checks them correctly.
+
         # FUTURE: This is where the basket_add hook was called.
 
         (_, created) = BasketItem.objects.update_or_create(
@@ -418,6 +424,16 @@ def create_basket_with_products(request):
             {"error": "Product not found"}, status=status.HTTP_404_NOT_FOUND
         )
 
+    allow_multiple_items = getattr(settings, "ENABLE_MULTIPLE_CART_ITEMS", False)
+    if not allow_multiple_items:
+        if len(products) > 1:
+            return Response(
+                {"error": "Multiple cart items are not enabled."},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+        basket.basket_items.all().delete()
+        BasketDiscount.objects.filter(redeemed_basket=basket).delete()
+
     try:
         for product, quantity in products:
             # FUTURE: this is where the basket_add hook is called

ecommerce/views/v0/views_test.py

@@ -11,7 +11,7 @@
 import pytest
 import reversion
 from django.forms.models import model_to_dict
-from django.test import Client
+from django.test import Client, override_settings
 from django.urls import reverse
 from django.utils.dateparse import parse_datetime
 from mitol.common.utils.datetime import now_in_utc
@@ -342,6 +342,7 @@ def test_add_basket_item(user_drf_client, user):
 @pytest.mark.parametrize("existing_basket", [True, False])
 @pytest.mark.parametrize("add_discount", [True, False])
 @pytest.mark.parametrize("bad_product", [True, False])
+@override_settings(ENABLE_MULTIPLE_CART_ITEMS=True)
 def test_create_basket_with_products(
     user, user_client, existing_basket, add_discount, bad_product
 ):

main/settings.py

@@ -39,7 +39,7 @@
 from main.sentry import init_sentry
 from openapi.settings_spectacular import open_spectacular_settings
 
-VERSION = "1.165.2"
+VERSION = "1.165.3"
 
 log = logging.getLogger()