Enhance FastAPI's Route Ordering to Prevent Unintended Matching

[linkedlist771]

First Check

• I added a very descriptive title here.
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Example Code

from fastapi import FastAPI

app = FastAPI() 

@app.get("/users/{user_id}")
async def read_user(user_id: str):
    return {"user_id": user_id}

@app.get("/users/me")
async def read_current_user():
    return {"user_id": "the current user"}

Description

When defining routes in FastAPI, the order matters. In the code above, a request to /users/me will actually be handled by the /users/{user_id} route because it's defined first, even though /users/me is a more specific route.

Operating System

Linux

Operating System Details

Operating System Details Ubuntu 20.04

FastAPI Version

0.108.0

Pydantic Version

2.5.2

Python Version

Python 3.10.14

Additional Context

This issue isn't causing a bug in my current project, but it's something I've run into before and I believe addressing it could improve FastAPI's usability and robustness.

I'm happy to provide any additional details or context if needed. And I'm excited to contribute back to the FastAPI community by helping others with their questions and issues moving forward.

Thanks for considering this suggestion and for all your amazing work on FastAPI!

[YuriiMotov]

I also thought that FastAPI could show warning if more specific paths declared after less specific one. It could be an optional feature

[linkedlist771]

I think there should be a PR to warn this router configs.