Passing UploadFile objects into a StreamingResponse closes it in v0.106.0 but not v0.105.0

[adrwz]

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Example Code

async def upload_file_event(files: List[UploadFile]):
    print("2", files[0].filename, files[0].file._file.closed)

    # ... more code ...


@router.post("/upload_session_file")
async def upload_file(files: List[UploadFile] = File(...)):
    print("1", files[0].filename, files[0].file._file.closed)

    try:
        return StreamingResponse(
            upload_file_event(files),
            media_type="text/event-stream",
        )
    except Exception as error:
        logging.error(error)
        raise HTTPException(status_code=500, detail="Internal Server Error")

Description

Hitting this endpoint with an uploaded file on v0.105.0 will print:

1 filename false
2 filename false

Hitting this endpoint with an uploaded file on v0.106.0 will print:

1 filename false
2 filename true

Unfortunately this means I'm unable to upload files in a StreamingResponse with fastapi>=0.106.0

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.105.0

Pydantic Version

2.5.3

Python Version

3.11.4

Additional Context

No response

[Kludex]

I've created #10857 from this discussion.