Can't get snapclient to start

[dotzeno]

Snapserver seems to be working just fine (tested by playing music via snapweb client).

Once I set START_SNAPCLIENT to true, logs show this repeatedly:
s6-applyuidgid: usage: s6-applyuidgid [ -z ] [ -u uid ] [ -g gid ] [ -G gidlist ] [ -U ] prog...

setting SNAPCLIENT_OPTS or adding device doesn't seem to change this.

snapclient is not present in the snap server web ui.

Is there a working example for how to setup snapclient using your docker image?

[sweisgerber-dev]

Please checkout:

• https://github.com/sweisgerber/docker-snapcast?tab=readme-ov-file#configuration-snapclient
• and the official documentation: https://github.com/badaix/snapcast?tab=readme-ov-file#client

Each system has a different audio device enumeration and setup and configurign snapclient is way less hassle with system packages.

In order for it to work:

1. you need to hand in an audio device into the docker, container like /dev/snd or some alsa loopback or a specific dedicated device for snapclient.
2. Start the docker image, but at first don't enable snapclient.
3. exec a shell inside the running snapcast docker: docker compose exec snapcast sh
4. Execute snapclient --list to find out available interfaces to snapclient inside the container and note down those numbers,

   root@snapcast:/# snapclient --list
   0: null
   Discard all samples (playback) or generate zero samples (capture)
   

5. Use this number with - SNAPCLIENT_OPTS=--host snapcast --soundcard <ID>

Keep in mind that the handed in audio devices get blocked (read: used exclusively) by the in-container audio stack.
The other way round: if the handed in audio device is already in use by the host, the in-container audio can't use it as well.

That's the reason, why I personally don't use snapclient from the container, only snapserver.

It's quite a hassle and you can work around it by utilizing more recent features of pulse audio, pipewire or utilize sth. like alsa loopback devices, but I don't have any working templates for you.

OS packages for snaclient have a close to zero setup need, so I strongly advise you to use that if possible. :)

OS System package for comparison:

cat /etc/default/snapclient -p                                                                                                                                                                        
# ---
START_SNAPCLIENT=true
#
# 24 has been found out via snapclient --list
#
SNAPCLIENT_OPTS="-s 24 -h 127.0.0.1 --hostId <NAME>"