Directory.export Use in Python

[nova snow]

I am trying to keep my dagger module as easy to use and minimising the input arguments for developers. So I want to use the built in Directory.export function to export build results from my container.
I have a function that builds code and returns a container object.
build_ctx = await self.build_core(source)
I've then tried to use this object to export a folder to the host
e.g. build_ctx.directory('/mnt/build-output-in-ctx').export("./build-out-on-host")
But nothing seems to be returned and I'm not seeing anything obvious in the traces that would indicate what's going wrong.

If I use the export argument then it works fine.

Am I doing something wrong with my code to do the export?

[fickle ivy]

Hey @nova snow! Dagger modules run in a sandboxed environment, which means that you're exporting exporting to the container where your module's code runs, instead of to your host. See https://docs.dagger.io/manuals/developer/execution-environment. You need to return the dagger.Directory in your function instead, and export using the CLI. See https://docs.dagger.io/manuals/user/export.

[nova snow]

Hi, thanks, so there's no way to export using code as I'm intending then?
From reading the documentation I thought this was possible, but then it sounds like I'm misunderstanding it
https://dagger-io.readthedocs.io/en/sdk-python-v0.13.5/client.html#dagger.Directory.export

[fickle ivy]

Yeah, I think "path on the host" is misleading. It's written like that because that API was created before modules, which still works today. But in a Dagger module, there's still a use case for it, but not for exporting to the host where you're running the CLI from. It'll export into the container where the module is running.

https://github.com/dagger/dagger/issues/8706