Merge pull request #203 from openedx/hu/ent-7114

feat: idempotent policies

enterprise_access/apps/api/serializers/subsidy_access_policy.py

@@ -99,9 +99,27 @@ class Meta:
             },
         }
 
+    @property
+    def calling_view(self):
+        """
+        Return the view that called this serializer.
+        """
+        return self.context['view']
+
     def create(self, validated_data):
         policy_type = validated_data.get('policy_type')
         policy_model = apps.get_model(app_label='subsidy_access_policy', model_name=policy_type)
+        filtered_policy = policy_model.objects.filter(
+            enterprise_customer_uuid=validated_data['enterprise_customer_uuid'],
+            subsidy_uuid=validated_data['subsidy_uuid'],
+            catalog_uuid=validated_data['catalog_uuid'],
+            access_method=validated_data['access_method'],
+            active=True,
+        ).first()
+        if filtered_policy:
+            self.calling_view.set_policy_created(False)
+            return filtered_policy
+        self.calling_view.set_policy_created(True)
         policy = policy_model.objects.create(**validated_data)
         return policy
 

enterprise_access/apps/api/v1/tests/test_subsidy_access_policy_views.py

@@ -351,6 +351,64 @@ def test_create_view(self, policy_type, extra_fields, expected_response_code, ex
             for expected_error_keyword in expected_error_keywords:
                 assert expected_error_keyword in response.content.decode("utf-8")
 
+    @ddt.data(
+        {
+            'policy_type': PolicyTypes.PER_LEARNER_SPEND_CREDIT,
+            'extra_fields': {
+                'per_learner_spend_limit': 30000,
+            },
+            'expected_response_code': status.HTTP_201_CREATED,
+        }
+    )
+    @ddt.unpack
+    def test_idempotent_create_view(self, policy_type, extra_fields, expected_response_code):
+        """
+        Test the (deprecated) policy create view's idempotency.
+        """
+        # Set the JWT-based auth that we'll use for every request
+        self.set_jwt_cookie([{'system_wide_role': SYSTEM_ENTERPRISE_ADMIN_ROLE, 'context': str(TEST_ENTERPRISE_UUID)}])
+
+        # Test the retrieve endpoint
+        create_url = SUBSIDY_ACCESS_POLICY_ADMIN_LIST_ENDPOINT
+        enterprise_customer_uuid = str(TEST_ENTERPRISE_UUID)
+        catalog_uuid = str(uuid4())
+        subsidy_uuid = str(uuid4())
+        payload = {
+            'policy_type': policy_type,
+            'description': 'test description',
+            'active': True,
+            'enterprise_customer_uuid': enterprise_customer_uuid,
+            'catalog_uuid': catalog_uuid,
+            'subsidy_uuid': subsidy_uuid,
+            'access_method': AccessMethods.DIRECT,
+            'spend_limit': None,
+        }
+        payload.update(extra_fields)
+        response = self.client.post(create_url, payload)
+        assert response.status_code == expected_response_code
+
+        if expected_response_code == status.HTTP_201_CREATED:
+            response_json = response.json()
+            del response_json['uuid']
+            expected_response = payload.copy()
+            expected_response.setdefault("per_learner_enrollment_limit")
+            expected_response.setdefault("per_learner_spend_limit")
+            assert response_json == expected_response
+
+        # Test idempotency
+        response = self.client.post(create_url, payload)
+        duplicate_status_code = status.HTTP_200_OK
+
+        assert response.status_code == duplicate_status_code
+
+        if response.status_code == status.HTTP_200_OK:
+            response_json = response.json()
+            del response_json['uuid']
+            expected_response = payload.copy()
+            expected_response.setdefault("per_learner_enrollment_limit")
+            expected_response.setdefault("per_learner_spend_limit")
+            assert response_json == expected_response
+
 
 @ddt.ddt
 class TestPolicyRedemptionAuthNAndPermissionChecks(APITestWithMocks):

enterprise_access/apps/api/v1/views/subsidy_access_policy.py

@@ -145,6 +145,13 @@ class SubsidyAccessPolicyCRUDViewset(PermissionRequiredMixin, viewsets.ModelView
     # impossible for learners to create policies.
     permission_required = REQUESTS_ADMIN_LEARNER_ACCESS_PERMISSION
 
+    def __init__(self, *args, **kwargs):
+        self.extra_context = {}
+        super().__init__(*args, **kwargs)
+
+    def set_policy_created(self, created):
+        self.extra_context['created'] = created
+
     @property
     def requested_enterprise_customer_uuid(self):
         """
@@ -183,11 +190,14 @@ def create(self, request, *args, **kwargs):
         serializer = self.get_serializer(data=policy_data)
         serializer.is_valid(raise_exception=True)
         serializer.save()
+        policy_created = self.extra_context.get('created')
         send_access_policy_event_to_event_bus(
             ACCESS_POLICY_CREATED.event_type,
             serializer.data
         )
-        return Response(serializer.data, status=status.HTTP_201_CREATED)
+        if policy_created:
+            return Response(serializer.data, status=status.HTTP_201_CREATED)
+        return Response(serializer.data, status=status.HTTP_200_OK)
 
     @extend_schema(
         tags=[SUBSIDY_ACCESS_POLICY_CRUD_API_TAG],