Support for bytes like object in File class

[infohash]

File class takes path of the file on the disk. This assumes that the file to be returned in the File Response already exists. However, if you are exporting some data from the database in the form of csv, a bytes like object of the dataframe is enough to send it as a file. While, it can be done with using generic Response class, its OpenAPI schema doesn't show that it returns a file object.

Improvement

Just like pandas.Dataframe.to_csv path_or_buf argument also accepts bytes buffer as the parameter, we can have the same functionality here in File. What do you think?

[Goldziher]

i dont see the use case tbh. are there any other interested parties?

[mike0sv]

yes. any use-case when you want to generate file dynamically in-memory

[provinzkraut]

But why would you want to use the file response then? It's specifically designed to serve files from a file system. If you already have the bytes at hand, why not just send those directly?

[mike0sv]

I want response to look like file. For now I am using

def ..... -> Reponse:
  ...
  return Response(
        buf.getvalue(),
        headers={"content-disposition": f"attachment;filename=..."},
    )

Is there a better way?

[provinzkraut]

Is there a better way?

Is there something wrong with your way?

You could even do something like this if you want to reuse it:

class InMemoryFileResponse(Response[bytes]):
    def __init__(self, buf: IO, name: str) -> None:
        super().__init__(
            buf.getvalue(), 
            headers={"content-disposition": f"attachment;filename={name}"
        )


@get("/")
async def handler() -> InMemoryFileResponse:
  buf = get_buffer()
  return InMemoryFileResponse(buf, name="something")