FastAPI: How to get raw URL path from request?

user_5165164 0
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I have a GET method with requested parameter in path:

@router.get('/users/{user_id}')
async def get_user_from_string(user_id: str):
    return User(user_id)

Is it possible to get base url raw path (i.e., '/users/{user_id}') from the request?

I have tried to use the following way:

path = [route for route in request.scope['router'].routes if
        route.endpoint == request.scope['endpoint']][0].path

But it doesn't work and I get:

AttributeError: 'Mount' object has no attribute 'endpoint'

fastapi url-routing python
4 Answers

As per FastAPI documentation:

As FastAPI is actually Starlette underneath, with a layer of several tools on top, you can use Starlette's Request object directly when you need to.

Thus, you can use Request object to get the URL path. For instance:

from fastapi import FastAPI, Request

app = FastAPI()

@app.get('/users/{user_id}')
def get_user(user_id: str, request: Request):
    return request.url.path

The above will return, for example, /users/1 (if user_id passed is 1).

Update

If, however, what you need is the original route path, i.e., /users/{user_id}, you could use the below. The way it works is by getting the root_path first—which would normally be an empty string, unless you have mounted sub-application(s) to the top-level app (e.g., app.mount("/subapi", subapi)), and hence, you need the result to be prefixed with that specific path /subapi—and then append to it the route's path , which you can get from the APIRoute object. Example:

from fastapi import FastAPI, Request

app = FastAPI()
    
@app.get('/users/{user_id}')
def get_user(user_id: str, request: Request):
    path = request.scope['root_path'] + request.scope['route'].path
    return path
user_178658040

I'm working on implementing this for OpenTelemetry and the way to get the original route with the data that's available is as follows:

def get_route_from_request(req):
  root_path = req.scope.get("root_path", "")

  route = scope.get("route")
  if not route:
    return None
  path_format = getattr(route, "path_format", None)
  if path_format:
    return f"{route_path}{path_format}"

  return None

Note that the accepted answer is not returning what was asked, as it returns the path as received by the server.

None of the other answers deal with mounted apps.

And finally, answers checking the name of the endpoint are also wrong as the same function could be used in different endpoints.

user_14136870

Having found both the answers to not work I'll share what I use. It's not great as if there's shared values in path params it will not work

path = request.url.path
for key, val in request.path_params.items():
    path = path.replace(val, F'{{{key}}}')
user_105014590

you can use APIRouter object attribute from Request to get real path

example:

raw_path = request.scope['route'].path 
#'/user/{id}'
user_193575690
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