feat: Customize serialization of request body

src/meatie/internal/template/request.py

@@ -12,7 +12,7 @@
 
 from meatie import Method, Request
 from meatie.api_reference import ApiReference
-from meatie.internal.adapter import JsonAdapter, TypeAdapter, get_adapter
+from meatie.internal.adapter import JsonAdapter, StringAdapter, TypeAdapter, get_adapter
 from meatie.internal.types import PT, RequestBodyType, T
 from typing_extensions import Callable, Self, Union, get_type_hints
 
@@ -73,7 +73,8 @@ def build_request(self, *args: Any, **kwargs: Any) -> Request:
 
         path_kwargs = {}
         query_kwargs = {}
-        body_value: Any = None
+        body_json: Any = None
+        body_data: Any = None
         for param, value in value_by_param.items():
             if param.kind == Kind.PATH:
                 if param.formatter is not None:
@@ -93,27 +94,27 @@ def build_request(self, *args: Any, **kwargs: Any) -> Request:
 
                 if param.formatter is not None:
                     value = param.formatter(value)
+
                 query_kwargs[param.api_ref] = value
                 continue
 
             if param.kind == Kind.BODY:
                 if param.formatter is not None:
-                    body_value = param.formatter(value)
+                    body_data = param.formatter(value)
                 else:
-                    body_value = value
+                    body_json = self.request_encoder.to_content(value)
                 continue
 
             raise NotImplementedError(f"Kind {param.kind} is not supported")  # pragma: no cover
 
         path = self.template.format(**path_kwargs)
-
-        if body_value is not None:
-            body_json = self.request_encoder.to_content(body_value)
-        else:
-            body_json = None
-
         return Request(
-            method=self.method, path=path, params=query_kwargs, headers={}, json=body_json
+            method=self.method,
+            path=path,
+            params=query_kwargs,
+            headers={},
+            json=body_json,
+            data=body_data,
         )
 
     @classmethod
@@ -146,7 +147,11 @@ def from_signature(
             kind = Kind.QUERY
             if api_ref.name == "body":
                 kind = Kind.BODY
-                request_encoder = get_adapter(param_type)
+                if api_ref.fmt is None:
+                    request_encoder = get_adapter(param_type)
+                else:
+                    request_encoder = StringAdapter
+
             elif api_ref.name in template:
                 kind = Kind.PATH
 

tests/client/aiohttp/adapter/test_pydantic_v2.py

@@ -0,0 +1,52 @@
+#  Copyright 2024 The Meatie Authors. All rights reserved.
+#  Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
+import json
+from http import HTTPStatus
+from http.server import BaseHTTPRequestHandler
+from typing import Annotated, Any, Optional
+
+import pytest
+from aiohttp import ClientSession
+from http_test import HTTPTestServer
+from meatie import AsyncResponse, api_ref, endpoint
+from meatie_aiohttp import Client
+
+pydantic = pytest.importorskip("pydantic", minversion="2.0.0")
+BaseModel: type = pydantic.BaseModel
+
+
+@pytest.mark.asyncio()
+async def test_post_request_body_with_fmt(http_server: HTTPTestServer) -> None:
+    # GIVEN
+    class Request(pydantic.BaseModel):
+        data: Optional[dict[str, Any]]
+
+    def handler(request: BaseHTTPRequestHandler) -> None:
+        content_length = request.headers.get("Content-Length", "0")
+        raw_body = request.rfile.read(int(content_length))
+        body = json.loads(raw_body.decode("utf-8"))
+
+        if body.get("data") is not None:
+            request.send_response(HTTPStatus.BAD_REQUEST)
+        else:
+            request.send_response(HTTPStatus.OK)
+        request.end_headers()
+
+    http_server.handler = handler
+
+    def dump_body(model: pydantic.BaseModel) -> str:
+        return model.model_dump_json(by_alias=True, exclude_none=True)
+
+    class TestClient(Client):
+        @endpoint("/")
+        async def post_request(
+            self, body: Annotated[Request, api_ref(fmt=dump_body)]
+        ) -> AsyncResponse:
+            ...
+
+    # WHEN
+    async with TestClient(ClientSession(http_server.base_url)) as client:
+        response = await client.post_request(Request(data=None))
+
+    # THEN
+    assert response.status == HTTPStatus.OK