Catching routes based on path parameter types

First Check

• I added a very descriptive title to this issue.
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Commit to Help

• I commit to help with one of those options 👆

Example Code

class SubType(Enum):
    thriller = "thriller"
    horror = "horror"

@router.get("/{id}-{subType}")
async def article_func_a(id: int, subType: SubType):
    return "show article with subtype"

@router.get("/{id}-{subId}")
async def article_func_b(id: int, subId: int):
    return "show article with subId"

Description

TL;DR

Is there a way to perform routing based on the data types of the path parameters? Instead of just the pattern of the path?

Explanation

Hi,

I am designing an application which will have two different types of routes:

1. {id}-{subType}

• Such as /1129-horror

1. {id}-{subId}

• Such as /1129-32

When I use the code above, the first given route catches both types of URLs, and throws validation error. Because routing is based on the parameter, and doesn’t care about the type of those parameters.

I am currently porting a Flask application, and it is doable in Flask by specifying types in routes such as: /<int:id>-<string:subType>. But apparently this isn’t possible in FastAPI.

I can convert enums into saperate routes, but I have dozens of subTypes, and that won’t be the most optimal solution. Especially when I am generating OpenAPI schema.

Operating System

Linux, Windows, macOS

Operating System Details

No response

FastAPI Version

0.79.0

Python Version

3.10.0

Additional Context

No response

[JarroVGIT]

My solution is not a workaround, it is the proper implementation of your requirements. But to answer your question; yes it results in the correct schema (otherwise it would be a workaround). You can try and see for your self in the generated /docs:

[AliFlux]

Thanks for the solution. It really works 🚀