How to log operation id and status for each route?

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Example Code

@app.middleware("http")
async def log(request, call_next):
    response = call_next(request)
    if response.status_code >= 300:
        return response
    operation_id = get_operation_id_somehow() # is this possible?
    print("LOG", operation_id, get_access_token(request))
    return response

Description

I want to log the Operation ID, as well as the access token (from the request) for all requests that did not error, is this at all possible right now?

Given that I want to do this for all endpoints, using a middleware seems reasonable, but they have no way of accessing the route information (including the operation id). I can get the other bits of information from the requests/response no problem.

I also considered using a dependency, but even dependencies seem unable to have access to the operation id.

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.65.2

Python Version

Python 3.9.1

Additional Context

No response

[ifigueroap]

I’m currently working on the same situation… this seems to work so far:

"""Instrumentation for registering requests and responses."""

import logging
from typing import Callable

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

logger = logging.getLogger(__name__)


class LoggingRoute(APIRoute):  # noqa
    def get_route_handler(self) -> Callable:  # noqa
        original_route_handler = super().get_route_handler()

        async def custom_route_handler(request: Request) -> Response:  # noqa
            logger.warning("====REQUEST SCOPE====")
            logger.warning(request.scope)
            logger.warning("=====================")

            logger.warning("====REQUEST BODY JSON====")
            body_json = await request.json()
            logger.warning(body_json)
            logger.warning("=====================")

            response = await original_route_handler(request)

            logger.warning("====RESPONSE JSON====")
            logger.warning(response.body)
            logger.warning("=====================")
            return response

        return custom_route_handler

However, you need to inject this class into the router before adding routes to it because the (internal?) add_route method uses the route_class constructor to create the routes, hence it cannot be overriden afterwards…

An example on how to do this:

router = APIRouter(prefix="/foo", route_class=LoggingRoute)

@router.post(...)
def post_method(...)
    # etc

[ojii]

I’ve ended up using the solution suggested in https://github.com/tiangolo/fastapi/issues/3877#issuecomment-916162837