Question
We are writing a web service using Python FastAPI that is going to be hosted
in Kubernetes. For auditing purposes, we need to save the raw JSON body of the
request/response for specific routes. The body size of both request
and response JSON is about 1MB , and preferably, this should not impact
the response time. How can we do that?
Answer
You may try to customize [APIRouter](https://fastapi.tiangolo.com/advanced/custom-request-and- route/#custom-apiroute-class-in-a-router) like in FastAPI official documentation:
import time
from typing 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()
response: Response = await original_route_handler(request)
duration = time.time() - before
response.headers["X-Response-Time"] = str(duration)
print(f"route duration: {duration}")
print(f"route response: {response}")
print(f"route response headers: {response.headers}")
return response
return custom_route_handler
app = FastAPI()
router = APIRouter(route_class=TimedRoute)
@app.get("/")
async def not_timed():
return {"message": "Not timed"}
@router.get("/timed")
async def timed():
return {"message": "It's the time of my life"}
app.include_router(router)
