perf(userReports): remove count from API response DEV-1354 (#6505)

### 📣 Summary
Improve user report performance by removing the expensive count
calculation from the response.

### 📖 Description
This change removes the `count` field from the user report API response
because calculating the total number of documents is a major bottleneck
on large datasets. The count query requires scanning the entire
collection, significantly slowing down the endpoint. Clients still
receive the paginated results as before, just without the heavy count
operation.

Author: noliveleger

jsapp/js/api/models/paginatedUserReportsListResponseList.ts

@@ -12,7 +12,6 @@ The endpoints are grouped by area of intended use. Each category contains relate
 import type { UserReportsListResponse } from './userReportsListResponse'
 
 export interface PaginatedUserReportsListResponseList {
-  count: number
   /** @nullable */
   next?: string | null
   /** @nullable */

kobo/apps/user_reports/tests/test_user_reports.py

@@ -21,14 +21,17 @@
     refresh_user_reports_materialized_view,
 )
 from kpi.tests.base_test_case import BaseTestCase
+from kpi.urls.router_api_v2 import URL_NAMESPACE as ROUTER_URL_NAMESPACE
 
 
 class UserReportsViewSetAPITestCase(BaseTestCase):
+
     fixtures = ['test_data']
+    URL_NAMESPACE = ROUTER_URL_NAMESPACE
 
     def setUp(self):
         self.client.login(username='adminuser', password='pass')
-        self.url = reverse(self._get_endpoint('api_v2:user-reports-list'))
+        self.url = reverse(self._get_endpoint('user-reports-list'))
 
         self.someuser = User.objects.get(username='someuser')
         self.organization = self.someuser.organization
@@ -261,7 +264,7 @@ def test_accepted_tos_field(self):
         self.assertEqual(results[0]['accepted_tos'], False)
 
         # POST to the tos endpoint to accept the terms of service
-        tos_url = reverse(self._get_endpoint('tos'))
+        tos_url = reverse('tos')
         response = self.client.post(tos_url)
         assert response.status_code == status.HTTP_204_NO_CONTENT
 
@@ -311,11 +314,13 @@ def _get_someuser_data(self):
 
 
 class UserReportsFilterAndOrderingTestCase(BaseTestCase):
+
     fixtures = ['test_data']
+    URL_NAMESPACE = ROUTER_URL_NAMESPACE
 
     def setUp(self):
         self.client.login(username='adminuser', password='pass')
-        self.url = reverse(self._get_endpoint('api_v2:user-reports-list'))
+        self.url = reverse(self._get_endpoint('user-reports-list'))
 
         self.someuser = User.objects.get(username='someuser')
         self.organization = self.someuser.organization
@@ -332,21 +337,23 @@ def _get_results(self, params=None):
 
     def test_username_prefix_filter(self):
         res = self._get_results({'q': 'username__icontains:some'})
-        self.assertEqual(res['count'], 1)
+        self.assertEqual(len(res['results']), 1)
         self.assertEqual(res['results'][0]['username'], 'someuser')
 
     def test_email_prefix_filter(self):
         res = self._get_results({'q': 'email__icontains:some@user'})
-        self.assertEqual(res['count'], 1)
+        self.assertEqual(len(res['results']), 1)
         self.assertEqual(res['results'][0]['email'], '[email protected]')
 
     def test_date_joined_gte_and_lte_filters(self):
-        all_res = self._get_results()
-        res_all = self._get_results({'q': 'date_joined__gte:2012-01-01'})
-        self.assertLessEqual(res_all['count'], all_res['count'])
+        all_results = self._get_results()
+        filtered_results = self._get_results({'q': 'date_joined__gte:2012-01-01'})
+        self.assertLessEqual(
+            len(filtered_results['results']), len(all_results['results'])
+        )
 
-        res_none = self._get_results({'q': 'date_joined__gte:3020-01-01'})
-        self.assertEqual(res_none['count'], 0)
+        no_results = self._get_results({'q': 'date_joined__gte:3020-01-01'})
+        self.assertEqual(len(no_results['results']), 0)
 
     def test_storage_bytes_gte_and_lte_filters(self):
         # Update someuser's storage to simulate storage usage

kobo/apps/user_reports/views.py

@@ -9,7 +9,7 @@
 from kobo.apps.user_reports.models import UserReports
 from kobo.apps.user_reports.seralizers import UserReportsSerializer
 from kpi.filters import SearchFilter
-from kpi.paginators import LimitOffsetPagination
+from kpi.paginators import NoCountPagination
 from kpi.permissions import IsAuthenticated
 from kpi.schema_extensions.v2.user_reports.serializers import UserReportsListResponse
 from kpi.utils.schema_extensions.markdown import read_md
@@ -40,7 +40,7 @@ class UserReportsViewSet(mixins.ListModelMixin, viewsets.GenericViewSet):
 
     queryset = UserReports.objects.all()
     serializer_class = UserReportsSerializer
-    pagination_class = LimitOffsetPagination
+    pagination_class = NoCountPagination
     permission_classes = (IsAuthenticated, SuperUserPermission)
     filter_backends = [DjangoFilterBackend, OrderingFilter, SearchFilter]
 
@@ -61,7 +61,6 @@ class UserReportsViewSet(mixins.ListModelMixin, viewsets.GenericViewSet):
     ]
     ordering = ['username']
     search_fields = ['username', 'email', 'first_name', 'last_name']
-    skip_distinct = True
 
     def list(self, request, *args, **kwargs):
         try:

static/openapi/schema_v2.json

@@ -17712,14 +17712,9 @@
             "PaginatedUserReportsListResponseList": {
                 "type": "object",
                 "required": [
-                    "count",
                     "results"
                 ],
                 "properties": {
-                    "count": {
-                        "type": "integer",
-                        "example": 123
-                    },
                     "next": {
                         "type": "string",
                         "nullable": true,

static/openapi/schema_v2.yaml

@@ -12804,12 +12804,8 @@ components:
     PaginatedUserReportsListResponseList:
       type: object
       required:
-      - count
       - results
       properties:
-        count:
-          type: integer
-          example: 123
         next:
           type: string
           nullable: true