Python: Correctly serialize enum with its value (#18327) (#18328)

modules/openapi-generator/src/main/resources/python/api_client.mustache

@@ -358,6 +358,8 @@ class ApiClient:
         """
         if obj is None:
             return None
+        elif isinstance(obj, Enum):
+            return obj.value
         elif isinstance(obj, SecretStr):
             return obj.get_secret_value()
         elif isinstance(obj, self.PRIMITIVE_TYPES):

modules/openapi-generator/src/test/resources/3_0/python/petstore-with-fake-endpoints-models-for-testing.yaml

@@ -894,6 +894,13 @@ paths:
             '*/*':
               schema:
                 $ref: '#/components/schemas/OuterObjectWithEnumProperty'
+      parameters:
+        - in: query
+          name: param
+          schema:
+            type: array
+            items:
+                $ref: '#/components/schemas/OuterEnumInteger'
       requestBody:
         required: true
         content:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/api_client.py

@@ -351,6 +351,8 @@ class ApiClient:
         """
         if obj is None:
             return None
+        elif isinstance(obj, Enum):
+            return obj.value
         elif isinstance(obj, SecretStr):
             return obj.get_secret_value()
         elif isinstance(obj, self.PRIMITIVE_TYPES):

samples/client/echo_api/python/openapi_client/api_client.py

@@ -351,6 +351,8 @@ class ApiClient:
         """
         if obj is None:
             return None
+        elif isinstance(obj, Enum):
+            return obj.value
         elif isinstance(obj, SecretStr):
             return obj.get_secret_value()
         elif isinstance(obj, self.PRIMITIVE_TYPES):

samples/openapi3/client/petstore/python-aiohttp/docs/FakeApi.md

@@ -632,7 +632,7 @@ No authorization required
 [[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
 
 # **fake_property_enum_integer_serialize**
-> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property)
+> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
 
 
 
@@ -643,6 +643,7 @@ Test serialization of enum (int) properties with examples
 
 ```python
 import petstore_api
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.rest import ApiException
 from pprint import pprint
@@ -659,9 +660,10 @@ async with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
     api_instance = petstore_api.FakeApi(api_client)
     outer_object_with_enum_property = petstore_api.OuterObjectWithEnumProperty() # OuterObjectWithEnumProperty | Input enum (int) as post body
+    param = [petstore_api.OuterEnumInteger()] # List[OuterEnumInteger] |  (optional)
 
     try:
-        api_response = await api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property)
+        api_response = await api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
         print("The response of FakeApi->fake_property_enum_integer_serialize:\n")
         pprint(api_response)
     except Exception as e:
@@ -676,6 +678,7 @@ async with petstore_api.ApiClient(configuration) as api_client:
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
  **outer_object_with_enum_property** | [**OuterObjectWithEnumProperty**](OuterObjectWithEnumProperty.md)| Input enum (int) as post body | 
+ **param** | [**List[OuterEnumInteger]**](OuterEnumInteger.md)|  | [optional] 
 
 ### Return type
 

samples/openapi3/client/petstore/python-aiohttp/petstore_api/api/fake_api.py

@@ -25,6 +25,7 @@ from petstore_api.models.enum_class import EnumClass
 from petstore_api.models.file_schema_test_class import FileSchemaTestClass
 from petstore_api.models.health_check_result import HealthCheckResult
 from petstore_api.models.outer_composite import OuterComposite
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.models.pet import Pet
 from petstore_api.models.tag import Tag
@@ -2179,6 +2180,7 @@ class FakeApi:
     async def fake_property_enum_integer_serialize(
         self,
         outer_object_with_enum_property: Annotated[OuterObjectWithEnumProperty, Field(description="Input enum (int) as post body")],
+        param: Optional[List[OuterEnumInteger]] = None,
         _request_timeout: Union[
             None,
             Annotated[StrictFloat, Field(gt=0)],
@@ -2198,6 +2200,8 @@ class FakeApi:
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request. If one
                                  number provided, it will be total request
                                  timeout. It can also be a pair (tuple) of
@@ -2222,6 +2226,7 @@ class FakeApi:
 
         _param = self._fake_property_enum_integer_serialize_serialize(
             outer_object_with_enum_property=outer_object_with_enum_property,
+            param=param,
             _request_auth=_request_auth,
             _content_type=_content_type,
             _headers=_headers,
@@ -2246,6 +2251,7 @@ class FakeApi:
     async def fake_property_enum_integer_serialize_with_http_info(
         self,
         outer_object_with_enum_property: Annotated[OuterObjectWithEnumProperty, Field(description="Input enum (int) as post body")],
+        param: Optional[List[OuterEnumInteger]] = None,
         _request_timeout: Union[
             None,
             Annotated[StrictFloat, Field(gt=0)],
@@ -2265,6 +2271,8 @@ class FakeApi:
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request. If one
                                  number provided, it will be total request
                                  timeout. It can also be a pair (tuple) of
@@ -2289,6 +2297,7 @@ class FakeApi:
 
         _param = self._fake_property_enum_integer_serialize_serialize(
             outer_object_with_enum_property=outer_object_with_enum_property,
+            param=param,
             _request_auth=_request_auth,
             _content_type=_content_type,
             _headers=_headers,
@@ -2313,6 +2322,7 @@ class FakeApi:
     async def fake_property_enum_integer_serialize_without_preload_content(
         self,
         outer_object_with_enum_property: Annotated[OuterObjectWithEnumProperty, Field(description="Input enum (int) as post body")],
+        param: Optional[List[OuterEnumInteger]] = None,
         _request_timeout: Union[
             None,
             Annotated[StrictFloat, Field(gt=0)],
@@ -2332,6 +2342,8 @@ class FakeApi:
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request. If one
                                  number provided, it will be total request
                                  timeout. It can also be a pair (tuple) of
@@ -2356,6 +2368,7 @@ class FakeApi:
 
         _param = self._fake_property_enum_integer_serialize_serialize(
             outer_object_with_enum_property=outer_object_with_enum_property,
+            param=param,
             _request_auth=_request_auth,
             _content_type=_content_type,
             _headers=_headers,
@@ -2375,6 +2388,7 @@ class FakeApi:
     def _fake_property_enum_integer_serialize_serialize(
         self,
         outer_object_with_enum_property,
+        param,
         _request_auth,
         _content_type,
         _headers,
@@ -2384,6 +2398,7 @@ class FakeApi:
         _host = None
 
         _collection_formats: Dict[str, str] = {
+            'param': 'multi',
         }
 
         _path_params: Dict[str, str] = {}
@@ -2395,6 +2410,10 @@ class FakeApi:
 
         # process the path parameters
         # process the query parameters
+        if param is not None:
+            
+            _query_params.append(('param', param))
+            
         # process the header parameters
         # process the form parameters
         # process the body parameter

samples/openapi3/client/petstore/python-aiohttp/petstore_api/api_client.py

@@ -353,6 +353,8 @@ class ApiClient:
         """
         if obj is None:
             return None
+        elif isinstance(obj, Enum):
+            return obj.value
         elif isinstance(obj, SecretStr):
             return obj.get_secret_value()
         elif isinstance(obj, self.PRIMITIVE_TYPES):

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/docs/FakeApi.md

@@ -624,7 +624,7 @@ No authorization required
 [[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
 
 # **fake_property_enum_integer_serialize**
-> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property)
+> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
 
 
 
@@ -636,6 +636,7 @@ Test serialization of enum (int) properties with examples
 import time
 import os
 import petstore_api
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.rest import ApiException
 from pprint import pprint
@@ -652,9 +653,10 @@ async with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
     api_instance = petstore_api.FakeApi(api_client)
     outer_object_with_enum_property = petstore_api.OuterObjectWithEnumProperty() # OuterObjectWithEnumProperty | Input enum (int) as post body
+    param = [petstore_api.OuterEnumInteger()] # List[OuterEnumInteger] |  (optional)
 
     try:
-        api_response = await api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property)
+        api_response = await api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
         print("The response of FakeApi->fake_property_enum_integer_serialize:\n")
         pprint(api_response)
     except Exception as e:
@@ -668,6 +670,7 @@ async with petstore_api.ApiClient(configuration) as api_client:
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
  **outer_object_with_enum_property** | [**OuterObjectWithEnumProperty**](OuterObjectWithEnumProperty.md)| Input enum (int) as post body | 
+ **param** | [**List[OuterEnumInteger]**](OuterEnumInteger.md)|  | [optional] 
 
 ### Return type
 

samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/api/fake_api.py

@@ -31,6 +31,7 @@ from petstore_api.models.enum_class import EnumClass
 from petstore_api.models.file_schema_test_class import FileSchemaTestClass
 from petstore_api.models.health_check_result import HealthCheckResult
 from petstore_api.models.outer_composite import OuterComposite
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.models.pet import Pet
 from petstore_api.models.tag import Tag
@@ -1075,13 +1076,15 @@ class FakeApi:
             _request_auth=_params.get('_request_auth'))
 
     @validate_arguments
-    async def fake_property_enum_integer_serialize(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], **kwargs) -> OuterObjectWithEnumProperty:  # noqa: E501
+    async def fake_property_enum_integer_serialize(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], param : Optional[conlist(OuterEnumInteger)] = None, **kwargs) -> OuterObjectWithEnumProperty:  # noqa: E501
         """fake_property_enum_integer_serialize  # noqa: E501
 
         Test serialization of enum (int) properties with examples  # noqa: E501
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request.
                If one number provided, it will be total request
                timeout. It can also be a pair (tuple) of
@@ -1095,16 +1098,18 @@ class FakeApi:
         if '_preload_content' in kwargs:
             message = "Error! Please call the fake_property_enum_integer_serialize_with_http_info method with `_preload_content` instead and obtain raw data from ApiResponse.raw_data"  # noqa: E501
             raise ValueError(message)
-        return await self.fake_property_enum_integer_serialize_with_http_info(outer_object_with_enum_property, **kwargs)  # noqa: E501
+        return await self.fake_property_enum_integer_serialize_with_http_info(outer_object_with_enum_property, param, **kwargs)  # noqa: E501
 
     @validate_arguments
-    async def fake_property_enum_integer_serialize_with_http_info(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], **kwargs) -> ApiResponse:  # noqa: E501
+    async def fake_property_enum_integer_serialize_with_http_info(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], param : Optional[conlist(OuterEnumInteger)] = None, **kwargs) -> ApiResponse:  # noqa: E501
         """fake_property_enum_integer_serialize  # noqa: E501
 
         Test serialization of enum (int) properties with examples  # noqa: E501
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _preload_content: if False, the ApiResponse.data will
                                  be set to none and raw_data will store the
                                  HTTP response body without reading/decoding.
@@ -1131,7 +1136,8 @@ class FakeApi:
         _params = locals()
 
         _all_params = [
-            'outer_object_with_enum_property'
+            'outer_object_with_enum_property',
+            'param'
         ]
         _all_params.extend(
             [
@@ -1161,6 +1167,10 @@ class FakeApi:
 
         # process the query parameters
         _query_params = []
+        if _params.get('param') is not None:  # noqa: E501
+            _query_params.append(('param', _params['param']))
+            _collection_formats['param'] = 'multi'
+
         # process the header parameters
         _header_params = dict(_params.get('_headers', {}))
         # process the form parameters

samples/openapi3/client/petstore/python-pydantic-v1/docs/FakeApi.md

@@ -624,7 +624,7 @@ No authorization required
 [[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
 
 # **fake_property_enum_integer_serialize**
-> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property)
+> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
 
 
 
@@ -636,6 +636,7 @@ Test serialization of enum (int) properties with examples
 import time
 import os
 import petstore_api
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.rest import ApiException
 from pprint import pprint
@@ -652,9 +653,10 @@ with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
     api_instance = petstore_api.FakeApi(api_client)
     outer_object_with_enum_property = petstore_api.OuterObjectWithEnumProperty() # OuterObjectWithEnumProperty | Input enum (int) as post body
+    param = [petstore_api.OuterEnumInteger()] # List[OuterEnumInteger] |  (optional)
 
     try:
-        api_response = api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property)
+        api_response = api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
         print("The response of FakeApi->fake_property_enum_integer_serialize:\n")
         pprint(api_response)
     except Exception as e:
@@ -668,6 +670,7 @@ with petstore_api.ApiClient(configuration) as api_client:
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
  **outer_object_with_enum_property** | [**OuterObjectWithEnumProperty**](OuterObjectWithEnumProperty.md)| Input enum (int) as post body | 
+ **param** | [**List[OuterEnumInteger]**](OuterEnumInteger.md)|  | [optional] 
 
 ### Return type
 

samples/openapi3/client/petstore/python-pydantic-v1/petstore_api/api/fake_api.py

@@ -30,6 +30,7 @@ from petstore_api.models.enum_class import EnumClass
 from petstore_api.models.file_schema_test_class import FileSchemaTestClass
 from petstore_api.models.health_check_result import HealthCheckResult
 from petstore_api.models.outer_composite import OuterComposite
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.models.pet import Pet
 from petstore_api.models.tag import Tag
@@ -1202,18 +1203,20 @@ class FakeApi:
             _request_auth=_params.get('_request_auth'))
 
     @validate_arguments
-    def fake_property_enum_integer_serialize(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], **kwargs) -> OuterObjectWithEnumProperty:  # noqa: E501
+    def fake_property_enum_integer_serialize(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], param : Optional[conlist(OuterEnumInteger)] = None, **kwargs) -> OuterObjectWithEnumProperty:  # noqa: E501
         """fake_property_enum_integer_serialize  # noqa: E501
 
         Test serialization of enum (int) properties with examples  # noqa: E501
         This method makes a synchronous HTTP request by default. To make an
         asynchronous HTTP request, please pass async_req=True
 
-        >>> thread = api.fake_property_enum_integer_serialize(outer_object_with_enum_property, async_req=True)
+        >>> thread = api.fake_property_enum_integer_serialize(outer_object_with_enum_property, param, async_req=True)
         >>> result = thread.get()
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param async_req: Whether to execute the request asynchronously.
         :type async_req: bool, optional
         :param _request_timeout: timeout setting for this request.
@@ -1229,21 +1232,23 @@ class FakeApi:
         if '_preload_content' in kwargs:
             message = "Error! Please call the fake_property_enum_integer_serialize_with_http_info method with `_preload_content` instead and obtain raw data from ApiResponse.raw_data"  # noqa: E501
             raise ValueError(message)
-        return self.fake_property_enum_integer_serialize_with_http_info(outer_object_with_enum_property, **kwargs)  # noqa: E501
+        return self.fake_property_enum_integer_serialize_with_http_info(outer_object_with_enum_property, param, **kwargs)  # noqa: E501
 
     @validate_arguments
-    def fake_property_enum_integer_serialize_with_http_info(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], **kwargs) -> ApiResponse:  # noqa: E501
+    def fake_property_enum_integer_serialize_with_http_info(self, outer_object_with_enum_property : Annotated[OuterObjectWithEnumProperty, Field(..., description="Input enum (int) as post body")], param : Optional[conlist(OuterEnumInteger)] = None, **kwargs) -> ApiResponse:  # noqa: E501
         """fake_property_enum_integer_serialize  # noqa: E501
 
         Test serialization of enum (int) properties with examples  # noqa: E501
         This method makes a synchronous HTTP request by default. To make an
         asynchronous HTTP request, please pass async_req=True
 
-        >>> thread = api.fake_property_enum_integer_serialize_with_http_info(outer_object_with_enum_property, async_req=True)
+        >>> thread = api.fake_property_enum_integer_serialize_with_http_info(outer_object_with_enum_property, param, async_req=True)
         >>> result = thread.get()
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param async_req: Whether to execute the request asynchronously.
         :type async_req: bool, optional
         :param _preload_content: if False, the ApiResponse.data will
@@ -1272,7 +1277,8 @@ class FakeApi:
         _params = locals()
 
         _all_params = [
-            'outer_object_with_enum_property'
+            'outer_object_with_enum_property',
+            'param'
         ]
         _all_params.extend(
             [
@@ -1303,6 +1309,10 @@ class FakeApi:
 
         # process the query parameters
         _query_params = []
+        if _params.get('param') is not None:  # noqa: E501
+            _query_params.append(('param', _params['param']))
+            _collection_formats['param'] = 'multi'
+
         # process the header parameters
         _header_params = dict(_params.get('_headers', {}))
         # process the form parameters

samples/openapi3/client/petstore/python/docs/EnumSerialization.md

@@ -0,0 +1,11 @@
+# EnumSerialization
+
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/petstore/python/docs/FakeApi.md

@@ -632,7 +632,7 @@ No authorization required
 [[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
 
 # **fake_property_enum_integer_serialize**
-> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property)
+> OuterObjectWithEnumProperty fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
 
 
 
@@ -643,6 +643,7 @@ Test serialization of enum (int) properties with examples
 
 ```python
 import petstore_api
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.rest import ApiException
 from pprint import pprint
@@ -659,9 +660,10 @@ with petstore_api.ApiClient(configuration) as api_client:
     # Create an instance of the API class
     api_instance = petstore_api.FakeApi(api_client)
     outer_object_with_enum_property = petstore_api.OuterObjectWithEnumProperty() # OuterObjectWithEnumProperty | Input enum (int) as post body
+    param = [petstore_api.OuterEnumInteger()] # List[OuterEnumInteger] |  (optional)
 
     try:
-        api_response = api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property)
+        api_response = api_instance.fake_property_enum_integer_serialize(outer_object_with_enum_property, param=param)
         print("The response of FakeApi->fake_property_enum_integer_serialize:\n")
         pprint(api_response)
     except Exception as e:
@@ -676,6 +678,7 @@ with petstore_api.ApiClient(configuration) as api_client:
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
  **outer_object_with_enum_property** | [**OuterObjectWithEnumProperty**](OuterObjectWithEnumProperty.md)| Input enum (int) as post body | 
+ **param** | [**List[OuterEnumInteger]**](OuterEnumInteger.md)|  | [optional] 
 
 ### Return type
 

samples/openapi3/client/petstore/python/petstore_api/api/fake_api.py

@@ -25,6 +25,7 @@ from petstore_api.models.enum_class import EnumClass
 from petstore_api.models.file_schema_test_class import FileSchemaTestClass
 from petstore_api.models.health_check_result import HealthCheckResult
 from petstore_api.models.outer_composite import OuterComposite
+from petstore_api.models.outer_enum_integer import OuterEnumInteger
 from petstore_api.models.outer_object_with_enum_property import OuterObjectWithEnumProperty
 from petstore_api.models.pet import Pet
 from petstore_api.models.tag import Tag
@@ -2179,6 +2180,7 @@ class FakeApi:
     def fake_property_enum_integer_serialize(
         self,
         outer_object_with_enum_property: Annotated[OuterObjectWithEnumProperty, Field(description="Input enum (int) as post body")],
+        param: Optional[List[OuterEnumInteger]] = None,
         _request_timeout: Union[
             None,
             Annotated[StrictFloat, Field(gt=0)],
@@ -2198,6 +2200,8 @@ class FakeApi:
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request. If one
                                  number provided, it will be total request
                                  timeout. It can also be a pair (tuple) of
@@ -2222,6 +2226,7 @@ class FakeApi:
 
         _param = self._fake_property_enum_integer_serialize_serialize(
             outer_object_with_enum_property=outer_object_with_enum_property,
+            param=param,
             _request_auth=_request_auth,
             _content_type=_content_type,
             _headers=_headers,
@@ -2246,6 +2251,7 @@ class FakeApi:
     def fake_property_enum_integer_serialize_with_http_info(
         self,
         outer_object_with_enum_property: Annotated[OuterObjectWithEnumProperty, Field(description="Input enum (int) as post body")],
+        param: Optional[List[OuterEnumInteger]] = None,
         _request_timeout: Union[
             None,
             Annotated[StrictFloat, Field(gt=0)],
@@ -2265,6 +2271,8 @@ class FakeApi:
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request. If one
                                  number provided, it will be total request
                                  timeout. It can also be a pair (tuple) of
@@ -2289,6 +2297,7 @@ class FakeApi:
 
         _param = self._fake_property_enum_integer_serialize_serialize(
             outer_object_with_enum_property=outer_object_with_enum_property,
+            param=param,
             _request_auth=_request_auth,
             _content_type=_content_type,
             _headers=_headers,
@@ -2313,6 +2322,7 @@ class FakeApi:
     def fake_property_enum_integer_serialize_without_preload_content(
         self,
         outer_object_with_enum_property: Annotated[OuterObjectWithEnumProperty, Field(description="Input enum (int) as post body")],
+        param: Optional[List[OuterEnumInteger]] = None,
         _request_timeout: Union[
             None,
             Annotated[StrictFloat, Field(gt=0)],
@@ -2332,6 +2342,8 @@ class FakeApi:
 
         :param outer_object_with_enum_property: Input enum (int) as post body (required)
         :type outer_object_with_enum_property: OuterObjectWithEnumProperty
+        :param param:
+        :type param: List[OuterEnumInteger]
         :param _request_timeout: timeout setting for this request. If one
                                  number provided, it will be total request
                                  timeout. It can also be a pair (tuple) of
@@ -2356,6 +2368,7 @@ class FakeApi:
 
         _param = self._fake_property_enum_integer_serialize_serialize(
             outer_object_with_enum_property=outer_object_with_enum_property,
+            param=param,
             _request_auth=_request_auth,
             _content_type=_content_type,
             _headers=_headers,
@@ -2375,6 +2388,7 @@ class FakeApi:
     def _fake_property_enum_integer_serialize_serialize(
         self,
         outer_object_with_enum_property,
+        param,
         _request_auth,
         _content_type,
         _headers,
@@ -2384,6 +2398,7 @@ class FakeApi:
         _host = None
 
         _collection_formats: Dict[str, str] = {
+            'param': 'multi',
         }
 
         _path_params: Dict[str, str] = {}
@@ -2395,6 +2410,10 @@ class FakeApi:
 
         # process the path parameters
         # process the query parameters
+        if param is not None:
+            
+            _query_params.append(('param', param))
+            
         # process the header parameters
         # process the form parameters
         # process the body parameter

samples/openapi3/client/petstore/python/petstore_api/api_client.py

@@ -350,6 +350,8 @@ class ApiClient:
         """
         if obj is None:
             return None
+        elif isinstance(obj, Enum):
+            return obj.value
         elif isinstance(obj, SecretStr):
             return obj.get_secret_value()
         elif isinstance(obj, self.PRIMITIVE_TYPES):

samples/openapi3/client/petstore/python/petstore_api/models/enum_serialization.py

@@ -0,0 +1,37 @@
+# coding: utf-8
+
+"""
+    OpenAPI Petstore
+
+    This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+
+    The version of the OpenAPI document: 1.0.0
+    Generated by OpenAPI Generator (https://openapi-generator.tech)
+
+    Do not edit the class manually.
+"""  # noqa: E501
+
+
+from __future__ import annotations
+import json
+from enum import Enum
+from typing_extensions import Self
+
+
+class EnumSerialization(int, Enum):
+    """
+    EnumSerialization
+    """
+
+    """
+    allowed enum values
+    """
+    NUMBER_0 = 0
+    NUMBER_1 = 1
+
+    @classmethod
+    def from_json(cls, json_str: str) -> Self:
+        """Create an instance of EnumSerialization from a JSON string"""
+        return cls(json.loads(json_str))
+
+

samples/openapi3/client/petstore/python/test/test_enum_serialization.py

@@ -0,0 +1,33 @@
+# coding: utf-8
+
+"""
+    OpenAPI Petstore
+
+    This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+
+    The version of the OpenAPI document: 1.0.0
+    Generated by OpenAPI Generator (https://openapi-generator.tech)
+
+    Do not edit the class manually.
+"""  # noqa: E501
+
+
+import unittest
+
+from petstore_api.models.enum_serialization import EnumSerialization
+
+class TestEnumSerialization(unittest.TestCase):
+    """EnumSerialization unit test stubs"""
+
+    def setUp(self):
+        pass
+
+    def tearDown(self):
+        pass
+
+    def testEnumSerialization(self):
+        """Test EnumSerialization"""
+        # inst = EnumSerialization()
+
+if __name__ == '__main__':
+    unittest.main()

samples/openapi3/client/petstore/python/tests/test_api_client.py

@@ -9,11 +9,9 @@ $ cd OpenAPIetstore-python
 $ pytest
 """
 
-import os
-import time
-import atexit
-import weakref
 import unittest
+from enum import Enum
+
 from dateutil.parser import parse
 
 import petstore_api
@@ -155,6 +153,16 @@ class ApiClientTests(unittest.TestCase):
         result = self.api_client.sanitize_for_serialization(data)
         self.assertEqual(result, "1997-07-16T19:20:30.450000+01:00")
 
+    def test_sanitize_for_serialization_list_enum(self):
+        class EnumSerialization(int, Enum):
+            NUMBER_0 = 0
+            NUMBER_1 = 1
+
+        data = [EnumSerialization.NUMBER_1]
+        result = self.api_client.sanitize_for_serialization(data)
+        self.assertEqual(result, [1])
+        self.assertNotIsInstance(result[0], EnumSerialization)
+
     def test_sanitize_for_serialization_list(self):
         data = [1]
         result = self.api_client.sanitize_for_serialization(data)
@@ -203,10 +211,11 @@ class ApiClientTests(unittest.TestCase):
             "category2": "example2"
         }
         result = self.api_client.parameters_to_url_query([('value', dictionary)], {})
-        self.assertEqual(result, "value=%7B%22category%22%3A%20%22example%22%2C%20%22category2%22%3A%20%22example2%22%7D")
+        self.assertEqual(result,
-        
+                         "value=%7B%22category%22%3A%20%22example%22%2C%20%22category2%22%3A%20%22example2%22%7D")
+
     def test_parameters_to_url_query_complex_values(self):
-        data='value={"number": 1, "string": "str", "bool": true, "dict": {"number": 1, "string": "str", "bool": true}}'
+        data = 'value={"number": 1, "string": "str", "bool": true, "dict": {"number": 1, "string": "str", "bool": true}}'
         dictionary = {
             "number": 1,
             "string": "str",
@@ -218,10 +227,11 @@ class ApiClientTests(unittest.TestCase):
             }
         }
         result = self.api_client.parameters_to_url_query([('value', dictionary)], {})
-        self.assertEqual(result, 'value=%7B%22number%22%3A%201%2C%20%22string%22%3A%20%22str%22%2C%20%22bool%22%3A%20true%2C%20%22dict%22%3A%20%7B%22number%22%3A%201%2C%20%22string%22%3A%20%22str%22%2C%20%22bool%22%3A%20true%7D%7D')
+        self.assertEqual(result,
+                         'value=%7B%22number%22%3A%201%2C%20%22string%22%3A%20%22str%22%2C%20%22bool%22%3A%20true%2C%20%22dict%22%3A%20%7B%22number%22%3A%201%2C%20%22string%22%3A%20%22str%22%2C%20%22bool%22%3A%20true%7D%7D')
 
     def test_parameters_to_url_query_dict_values(self):
-        data='value={"strValues": ["one", "two", "three"], "dictValues": [{"name": "value1", "age": 14}, {"name": "value2", "age": 12}]}'
+        data = 'value={"strValues": ["one", "two", "three"], "dictValues": [{"name": "value1", "age": 14}, {"name": "value2", "age": 12}]}'
         dictionary = {
             "strValues": [
                 "one",
@@ -240,12 +250,14 @@ class ApiClientTests(unittest.TestCase):
             ]
         }
         result = self.api_client.parameters_to_url_query([('value', dictionary)], {})
-        self.assertEqual(result, 'value=%7B%22strValues%22%3A%20%5B%22one%22%2C%20%22two%22%2C%20%22three%22%5D%2C%20%22dictValues%22%3A%20%5B%7B%22name%22%3A%20%22value1%22%2C%20%22age%22%3A%2014%7D%2C%20%7B%22name%22%3A%20%22value2%22%2C%20%22age%22%3A%2012%7D%5D%7D')
+        self.assertEqual(result,
+                         'value=%7B%22strValues%22%3A%20%5B%22one%22%2C%20%22two%22%2C%20%22three%22%5D%2C%20%22dictValues%22%3A%20%5B%7B%22name%22%3A%20%22value1%22%2C%20%22age%22%3A%2014%7D%2C%20%7B%22name%22%3A%20%22value2%22%2C%20%22age%22%3A%2012%7D%5D%7D')
 
     def test_parameters_to_url_query_boolean_value(self):
         result = self.api_client.parameters_to_url_query([('boolean', True)], {})
         self.assertEqual(result, "boolean=true")
 
     def test_parameters_to_url_query_list_value(self):
-        params = self.api_client.parameters_to_url_query(params=[('list', [1, 2, 3])], collection_formats={'list': 'multi'})
+        params = self.api_client.parameters_to_url_query(params=[('list', [1, 2, 3])],
+                                                         collection_formats={'list': 'multi'})
         self.assertEqual(params, "list=1&list=2&list=3")

samples/openapi3/client/petstore/python/tests/test_fake_api.py

@@ -15,6 +15,8 @@ import unittest
 import unittest
 from unittest.mock import patch, Mock
 import petstore_api
+from petstore_api import OuterObjectWithEnumProperty, OuterEnumInteger
+
 
 class TestFakeApi(unittest.TestCase):
     """StrLikeJson unit test stubs"""
@@ -141,4 +143,25 @@ class TestFakeApi(unittest.TestCase):
             "petstore_api.api_client.ApiClient.call_api", return_value=mock_resp
         ):
             returned = self.fake_api.fake_return_byte_like_json()
-            self.assertEqual(b'{"a": "a"}', returned)
+            self.assertEqual(b'{"a": "a"}', returned)
+
+    def testIntEnumReturnsValue(self):
+        """
+        Fixes #18327 (https://github.com/OpenAPITools/openapi-generator/issues/18327)
+        The enum value should be used in the param and not the enum name
+        """
+        mock_resp = Mock()
+        mock_resp.status = 200
+        mock_resp.data = b'{"value": "0"}'
+        mock_resp.getheaders.return_value = {}
+        mock_resp.getheader = (
+            lambda name: "text/plain" if name == "content-type" else Mock()
+        )
+        with patch(
+                "petstore_api.api_client.ApiClient.call_api", return_value=mock_resp
+        ) as call_api_mock:
+            self.fake_api.fake_property_enum_integer_serialize(
+                outer_object_with_enum_property=OuterObjectWithEnumProperty(value=OuterEnumInteger.NUMBER_0),
+                param=[OuterEnumInteger.NUMBER_0])
+            self.assertEqual(call_api_mock.call_args[0][1],
+                             'http://petstore.swagger.io:80/v2/fake/property/enum-int?param=0')