Re: How to make audio devices available with guix shell --container

[kiasoc5]

On 12/5/22 12:41, Elias Kueny wrote:
> Hello,
>
> I'm trying to run an online videoconferencing tool in chromium in a guix 
> shell with a container, so I expose my system as little as possible. All 
> is well without the --container option, but I'm not sure what to expose 
> to make it work in the container too.
>
> I'm on guix system. I'm starting the software with: `guix shell 
> --container -N -P --no-cwd --preserve='^DISPLAY$' 
> --preserve='^XAUTHORITY$' --share=$XAUTHORITY --share=/dev/video0 
> ungoogled-chromium -- chromium --app="https://meet.jit.si"`.
>
> `--preserve='^DISPLAY$' --preserve='^XAUTHORITY$' --share=$XAUTHORITY` 
> lets chromium open an X window and share the scren.
> `--share=/dev/video0` gives access to the webcam.
> What is the step to allow the microphone and speakers?

About the sound, I believe you will need to expose the pulseaudio and/or 
pipewire sockets. You can reference bubblewrap configuration since it 
also works by sharing/exposing files.

https://wiki.archlinux.org/title/Bubblewrap/Examples#Chromium

> I'm not particularly familiar with how audio devices are working. I read 
> they are in /dev/snd, but sharing this or even the whole of /dev/ 
> doesn't make the microphone and speakers available (although the browser 
> is now asking me for the permission to access them, so it seems aware I 
> have them). I also tried adding tinyalsa and pulseaudio to the container 
> in case that's what's missing, but to no avail. I didn't explicitely 
> install anything related to audio (but I have %desktop-services in my 
> operating-system definition), so if it's a software that is missing, I 
> don't know which one.

I believe in the case of ungoogled-chromium that pulseaudio is part of 
the inputs already.

> Thank you in advance!

It would be nice to have a tool for defining guix containers by 
permissions (with camera, with audio, etc) like bubblejail/firejail. 
That is a topic for a later mail.