I con‘t get requests.body when I set a new route_class

[yintian710]

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Example Code

from typing import Callable

from fastapi import Request, Response
from fastapi.routing import APIRoute
from starlette.datastructures import Headers


class Text2Json(Request):
    @property
    def headers(self) -> Headers:
        old_headers = self.scope['headers']
        new_headers = []
        for _ in old_headers:
            if _[0] != b'content-type':
                new_headers.append(_)
        new_headers.append((b'content-type', b'application/json'))
        self.scope['headers'] = new_headers
        self._headers = Headers(scope=self.scope)
        return self._headers


class Text2JsonRoute(APIRoute):
    def get_route_handler(self) -> Callable:
        original_route_handler = super().get_route_handler()

        async def custom_route_handler(request: Request) -> Response:
            content_type = request.headers.get('content-type', '')
            body1 = await request.body()
            if 'text' in content_type and 'json' not in content_type or not content_type:
                request = Text2Json(request.scope, request.receive)
            body2 = await request.body()
            return await original_route_handler(request)
        return custom_route_handler



from fastapi import APIRouter

from component.pn_tv_gs.HoGsVerifyData import HoGsVerifyData
from component.pn_tv_gs.TvVerifyData import TvVerifyData
from component.pn_tv_gs.verify_gs_pn import start as pn_tv_start
from component.pn_tv_gs.verify_tv import start as tv_start
from middleware.xx_text_to_json_type import Text2JsonRoute

pn_tv_gs = APIRouter(
    # prefix="/",
    tags=["pn_tv_gs"],
    # dependencies=[Depends(get_token_header)],
    # responses={404: {"description": "Not found"}},
)
pn_tv_gs.route_class = Text2JsonRoute


@pn_tv_gs.post('/verify_pn_gs')
async def _(data: HoGsVerifyData):
    result = pn_tv_start(data)
    return result


@pn_tv_gs.post('/verify_tv')
async def _(data: TvVerifyData):
    result = tv_start(data)
    return result

Description

I added a Text2JsonRoute that converts the content-type of the request from text to JSON,
But when I use POSTMAN to request http://host:port/verify_pn_gs and carry the body:{" body ", "body"}, which is fine when content-type is JSON, but when content-type is text, I can get body1, but I can't get body2, which seems to be stuck at line 205 in the requests module:Message = await self._receive().

Operating System

Linux

Operating System Details

ubutun 20.04

FastAPI Version

0.65.2

Python Version

3.8.10

Additional Context

No response