Duplicated OperationID when adding route with multiple methods

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Example Code

router.add_api_route(
    "/clear",
    clear,
    methods=["POST", "DELETE"]
)

Description

Seems to be caused by #4650.

The new generate_unique_id() function uses list(route.methods)[0].lower() as suffix for the operation_id. Therefore, in my example, both post and delete endpoints get _post suffix for operation_id, causing it to no longer be unique.

It then issues a “UserWarning: Duplicate Operation ID”

Operating System

Windows

Operating System Details

No response

FastAPI Version

0.75.0

Python Version

3.10.2

Additional Context

No response

[stapetro]

Hello @bneijt, I confirm I hit the same issue with fastapi@0.79.1. I’ve decorated a method like this:

@router.api_route(
    "/example",
    methods=["POST", "PUT"],
    status_code=status.HTTP_201_CREATED,
)
async def save_example(...)
  pass

[bruchar1]

No. @mbrav problem is unrelated to this.