# Custom Request and APIRoute class { #custom-request-and-apiroute-class }

In some cases, you may want to override the logic used by the `Request` and `APIRoute` classes.

In particular, this may be a good alternative to logic in a middleware.

For example, if you want to read or manipulate the request body before it is processed by your application.

/// danger

This is an "advanced" feature.

# 自訂 Request 與 APIRoute 類別 { #custom-request-and-apiroute-class }

在某些情況下，你可能想要覆寫 `Request` 與 `APIRoute` 類別所使用的邏輯。

特別是，這可能是替代中介軟體（middleware）中實作邏輯的一個好方法。

例如，如果你想在應用程式處理之前讀取或操作請求本文（request body）。

/// danger

這是進階功能。

如果你剛開始使用 **FastAPI**，可以先跳過本節。

///

## 使用情境 { #use-cases }

可能的使用情境包括：

* 將非 JSON 的請求本文轉換為 JSON（例如 [`msgpack`](https://msgpack.org/index.html)）。
* 解壓縮以 gzip 壓縮的請求本文。
* 自動記錄所有請求本文。

# 커스텀 Request 및 APIRoute 클래스 { #custom-request-and-apiroute-class }

일부 경우에는 `Request`와 `APIRoute` 클래스에서 사용되는 로직을 오버라이드하고 싶을 수 있습니다.

특히, 이는 middleware에 있는 로직의 좋은 대안이 될 수 있습니다.

예를 들어, 애플리케이션에서 처리되기 전에 요청 바디를 읽거나 조작하고 싶을 때가 그렇습니다.

/// danger | 위험

이 기능은 "고급" 기능입니다.

**FastAPI**를 이제 막 시작했다면 이 섹션은 건너뛰는 것이 좋습니다.

///

## 사용 사례 { #use-cases }

사용 사례에는 다음이 포함됩니다:

from collections.abc import Callable

from fastapi import Body, FastAPI, HTTPException, Request, Response
from fastapi.exceptions import RequestValidationError
from fastapi.routing import APIRoute


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

        async def custom_route_handler(request: Request) -> Response:
            try:

import time
from collections.abc import Callable

from fastapi import APIRouter, FastAPI, Request, Response
from fastapi.routing import APIRoute


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

        async def custom_route_handler(request: Request) -> Response:
            before = time.time()

from fastapi import FastAPI
from fastapi.routing import APIRoute

app = FastAPI()


@app.get("/items/")
async def read_items():
    return [{"item_id": "Foo"}]


def use_route_names_as_operation_ids(app: FastAPI) -> None:
    """
    Simplify operation IDs so that generated API clients have simpler function
    names.

    Should be called only after all routes have been added.
    """
    for route in app.routes:

from fastapi.routing import APIRoute


class GzipRequest(Request):
    async def body(self) -> bytes:
        if not hasattr(self, "_body"):
            body = await super().body()
            if "gzip" in self.headers.getlist("Content-Encoding"):
                body = gzip.decompress(body)
            self._body = body
        return self._body


class GzipRoute(APIRoute):
    def get_route_handler(self) -> Callable:

import pytest
from fastapi import APIRouter, FastAPI
from fastapi.routing import APIRoute
from fastapi.testclient import TestClient
from inline_snapshot import snapshot
from starlette.routing import Route

app = FastAPI()


class APIRouteA(APIRoute):
    x_type = "A"


class APIRouteB(APIRoute):
    x_type = "B"


class APIRouteC(APIRoute):
    x_type = "C"


router_a = APIRouter(route_class=APIRouteA)

from fastapi.routing import APIRoute


class GzipRequest(Request):
    async def body(self) -> bytes:
        if not hasattr(self, "_body"):
            body = await super().body()
            if "gzip" in self.headers.getlist("Content-Encoding"):
                body = gzip.decompress(body)
            self._body = body
        return self._body


class GzipRoute(APIRoute):
    def get_route_handler(self) -> Callable:

# カスタム Request と APIRoute クラス { #custom-request-and-apiroute-class }

場合によっては、`Request` や `APIRoute` クラスで使われるロジックを上書きしたいことがあります。

特に、ミドルウェアでのロジックの代替として有効な場合があります。

たとえば、アプリケーションで処理される前にリクエストボディを読み取ったり操作したりしたい場合です。

/// danger | 警告

これは「上級」機能です。

FastAPI を始めたばかりの場合は、このセクションは読み飛ばしてもよいでしょう。

///

## ユースケース { #use-cases }

ユースケースの例:

* JSON ではないリクエストボディを JSON に変換する（例: [`msgpack`](https://msgpack.org/index.html)）。