from fastapi import FastAPI
from fastapi.middleware.httpsredirect import HTTPSRedirectMiddleware

app = FastAPI()

app.add_middleware(HTTPSRedirectMiddleware)


@app.get("/")
async def main():

In einigen Fällen möchten Sie möglicherweise die von den Klassen `Request` und `APIRoute` verwendete Logik überschreiben.

Das kann insbesondere eine gute Alternative zur Logik in einer Middleware sein.

Wenn Sie beispielsweise den Requestbody lesen oder manipulieren möchten, bevor er von Ihrer Anwendung verarbeitet wird.

/// danger | "Gefahr"

Dies ist eine „fortgeschrittene“ Funktion.

import time

from fastapi import FastAPI, Request

app = FastAPI()


@app.middleware("http")
async def add_process_time_header(request: Request, call_next):
    start_time = time.perf_counter()
    response = await call_next(request)
    process_time = time.perf_counter() - start_time
    response.headers["X-Process-Time"] = str(process_time)

        state["sync_bg"] = (
            f"sync_bg set - b: {state['context_b']} - a: {state['context_a']}"
        )

    tasks.add_task(bg, state)
    return state


@app.middleware("http")
async def middleware(request, call_next):
    response: StreamingResponse = await call_next(request)
    response.headers["x-state"] = json.dumps(state.copy())
    return response


client = TestClient(app)

você precisa adicioná-los às suas configurações de CORS (saiba mais em [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), usando o parâmetro `expose_headers` descrito na <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">documentação de CORS do Starlette</a>....

      - tutorial/security/index.md
      - tutorial/security/first-steps.md
      - tutorial/security/get-current-user.md
      - tutorial/security/simple-oauth2.md
      - tutorial/security/oauth2-jwt.md
    - tutorial/middleware.md
    - tutorial/cors.md
    - tutorial/sql-databases.md
    - tutorial/bigger-applications.md
    - tutorial/background-tasks.md
    - tutorial/metadata.md
    - tutorial/static-files.md

# 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.

If you are just starting with **FastAPI** you might want to skip this section.

///

CORS-Konfigurationen hinzufügen (weitere Informationen finden Sie unter [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), unter Verwendung des Parameters `expose_headers`, dokumentiert in <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlettes CORS-Dokumentation</a>....

see, you need to add them to your CORS configurations (read more in [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), using the parameter `expose_headers` documented in <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette's CORS docs</a>....

class="external-link" target="_blank">⚙️ '✖-' 🔡</a>.

✋️ 🚥 👆 ✔️ 🛃 🎚 👈 👆 💚 👩‍💻 🖥 💪 👀, 👆 💪 🚮 👫 👆 ⚜ 📳 (✍ 🌅 [⚜ (✖️-🇨🇳 ℹ 🤝)](../tutorial/cors.md){.internal-link target=_blank}), ⚙️ 🔢 `expose_headers` 📄 <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">💃 ⚜ 🩺</a>....