fastapi_middleware.py

@app.middleware("http")
async def check_token(request: Request, _next) -> Response:
    if request.headers["apiKey"] != "this_is_my_key":
        return JSONResponse({"message": "Your key is mismatched"})

    start_time = time.time()
    response: Response = await _next(request)
    response.headers["X-Process-Time"] = str(time.time() - start_time)

    return response