fix(template): Properly strip out UNSET values from form data [#430]. Thanks @p1-ra!

* templates / endpoint_module / form_data: do not use `attr.asdict`, use <Model>.to_dict()` serializer

   - to handle internal UNSET values to not serialize them,
     `attr.asdict` do not know UNSET type and will serialize them

* e2e / update golden-record

Author: p1-ra

end_to_end_tests/golden-record/my_test_api_client/api/tests/post_form_data.py

@@ -0,0 +1,68 @@
+from typing import Any, Dict
+
+import httpx
+
+from ...client import Client
+from ...models.a_form_data import AFormData
+from ...types import Response
+
+
+def _get_kwargs(
+    *,
+    client: Client,
+    form_data: AFormData,
+) -> Dict[str, Any]:
+    url = "{}/tests/post_form_data".format(client.base_url)
+
+    headers: Dict[str, Any] = client.get_headers()
+    cookies: Dict[str, Any] = client.get_cookies()
+
+    return {
+        "url": url,
+        "headers": headers,
+        "cookies": cookies,
+        "timeout": client.get_timeout(),
+        "data": form_data.to_dict(),
+    }
+
+
+def _build_response(*, response: httpx.Response) -> Response[None]:
+    return Response(
+        status_code=response.status_code,
+        content=response.content,
+        headers=response.headers,
+        parsed=None,
+    )
+
+
+def sync_detailed(
+    *,
+    client: Client,
+    form_data: AFormData,
+) -> Response[None]:
+    kwargs = _get_kwargs(
+        client=client,
+        form_data=form_data,
+    )
+
+    response = httpx.post(
+        **kwargs,
+    )
+
+    return _build_response(response=response)
+
+
+async def asyncio_detailed(
+    *,
+    client: Client,
+    form_data: AFormData,
+) -> Response[None]:
+    kwargs = _get_kwargs(
+        client=client,
+        form_data=form_data,
+    )
+
+    async with httpx.AsyncClient() as _client:
+        response = await _client.post(**kwargs)
+
+    return _build_response(response=response)

end_to_end_tests/golden-record/my_test_api_client/models/__init__.py

@@ -1,5 +1,6 @@
 """ Contains all the data models used in inputs/outputs """
 
+from .a_form_data import AFormData
 from .a_model import AModel
 from .a_model_with_properties_reference_that_are_not_object import AModelWithPropertiesReferenceThatAreNotObject
 from .all_of_sub_model import AllOfSubModel

end_to_end_tests/golden-record/my_test_api_client/models/a_form_data.py

@@ -0,0 +1,63 @@
+from typing import Any, Dict, List, Type, TypeVar, Union
+
+import attr
+
+from ..types import UNSET, Unset
+
+T = TypeVar("T", bound="AFormData")
+
+
+@attr.s(auto_attribs=True)
+class AFormData:
+    """ """
+
+    an_required_field: str
+    an_optional_field: Union[Unset, str] = UNSET
+    additional_properties: Dict[str, Any] = attr.ib(init=False, factory=dict)
+
+    def to_dict(self) -> Dict[str, Any]:
+        an_required_field = self.an_required_field
+        an_optional_field = self.an_optional_field
+
+        field_dict: Dict[str, Any] = {}
+        field_dict.update(self.additional_properties)
+        field_dict.update(
+            {
+                "an_required_field": an_required_field,
+            }
+        )
+        if an_optional_field is not UNSET:
+            field_dict["an_optional_field"] = an_optional_field
+
+        return field_dict
+
+    @classmethod
+    def from_dict(cls: Type[T], src_dict: Dict[str, Any]) -> T:
+        d = src_dict.copy()
+        an_required_field = d.pop("an_required_field")
+
+        an_optional_field = d.pop("an_optional_field", UNSET)
+
+        a_form_data = cls(
+            an_required_field=an_required_field,
+            an_optional_field=an_optional_field,
+        )
+
+        a_form_data.additional_properties = d
+        return a_form_data
+
+    @property
+    def additional_keys(self) -> List[str]:
+        return list(self.additional_properties.keys())
+
+    def __getitem__(self, key: str) -> Any:
+        return self.additional_properties[key]
+
+    def __setitem__(self, key: str, value: Any) -> None:
+        self.additional_properties[key] = value
+
+    def __delitem__(self, key: str) -> None:
+        del self.additional_properties[key]
+
+    def __contains__(self, key: str) -> bool:
+        return key in self.additional_properties

end_to_end_tests/openapi.json

@@ -188,6 +188,36 @@
         }
       }
     },
+    "/tests/post_form_data": {
+      "post": {
+        "tags": [
+          "tests"
+        ],
+        "sumnary": "Post from data",
+        "description": "Post form data",
+        "operationId": "post_form_data",
+        "requestBody": {
+          "content": {
+            "application/x-www-form-urlencoded": {
+              "schema": {
+                "$ref": "#/components/schemas/AFormData"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "Successful Response",
+            "content": {
+              "application/json": {
+                "schema": {}
+              }
+            }
+          }
+        }
+      }
+    },
     "/tests/upload": {
       "post": {
         "tags": [
@@ -797,6 +827,20 @@
   },
   "components": {
     "schemas": {
+      "AFormData": {
+        "type": "object",
+        "properties": {
+          "an_optional_field": {
+            "type": "string"
+          },
+          "an_required_field": {
+            "type": "string"
+          }
+        },
+        "required": [
+          "an_required_field"
+        ]
+      },
       "AModel": {
         "title": "AModel",
         "required": [

openapi_python_client/templates/endpoint_module.py.jinja

@@ -1,7 +1,6 @@
 from typing import Any, Dict, List, Optional, Union, cast
 
 import httpx
-from attr import asdict
 
 from ...client import AuthenticatedClient, Client
 from ...types import Response, UNSET{% if endpoint.multipart_body_class %}, File {% endif %}
@@ -52,7 +51,7 @@ def _get_kwargs(
         "cookies": cookies,
         "timeout": client.get_timeout(),
         {% if endpoint.form_body_class %}
-        "data": asdict(form_data),
+        "data": form_data.to_dict(),
         {% elif endpoint.multipart_body_class %}
         "files": files,
         "data": data,