[RHCLOUD-36102] - Slow loading of data from roles endpoint performanc…

…e fixes (#1354)

Using prefetch_related for "access", "ext_relation" and "access__permission" reduced the number of queries from 33 to 6 for a request to the roles endpoint for the get_role_queryset method.

rbac/management/querysets.py

@@ -155,9 +155,9 @@ def get_role_queryset(request) -> QuerySet:
     """Obtain the queryset for roles."""
     scope = validate_and_get_key(request.query_params, SCOPE_KEY, VALID_SCOPES, ORG_ID_SCOPE)
     public_tenant = Tenant.objects.get(tenant_name="public")
-    base_query = annotate_roles_with_counts(Role.objects.prefetch_related("access")).filter(
-        tenant__in=[request.tenant, public_tenant]
-    )
+    base_query = annotate_roles_with_counts(
+        Role.objects.prefetch_related("access", "ext_relation", "access__permission")
+    ).filter(tenant__in=[request.tenant, public_tenant])
 
     if scope == PRINCIPAL_SCOPE:
         queryset = get_object_principal_queryset(

rbac/rbac/settings.py

@@ -84,7 +84,6 @@
 
 ALLOWED_HOSTS = ["*"]
 
-
 # Application definition
 
 INSTALLED_APPS = [

tests/internal/integration/test_integration_views.py

@@ -442,6 +442,7 @@ def test_roles_for_org(self, mock_request):
             **self.request.META,
             follow=True,
         )
+
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.data.get("meta").get("count"), 1)