MIDI file playing in a devcontainer

[jeandeaual]

I usually work inside a development container, and this extension works perfectly fine there, except for the MIDI file player: I get no error but no music is played.
I tried installing timidity, fluid-soundfont-gm and fluid-soundfont-gs, but this didn't help (the container is based on Debian).

Here is the configuration I use (files inside .devcontainer):

• Dockerfile:

  # [Choice] LilyPond version: 2.22.0, 2.23.0, etc.
  ARG VARIANT="2.23.0"
  FROM jeandeaual/lilypond:${VARIANT}
  
  ARG USERNAME=vscode
  ARG USER_UID=1000
  ARG USER_GID=$USER_UID
  
  RUN apt-get -o Acquire::Check-Valid-Until=false -o Acquire::Check-Date=false update && export DEBIAN_FRONTEND=noninteractive \
          && apt-get -y upgrade \
          && apt-get -y --no-install-recommends install sudo git vim timidity fluid-soundfont-gm fluid-soundfont-gs \
          && rm -rf /var/lib/apt/lists/*
  
  RUN groupadd --gid "${USER_GID}" "${USERNAME}"
  RUN useradd -s /bin/bash --uid "${USER_UID}" --gid "${USER_GID}" --groups sudo --create-home "${USERNAME}"
  RUN echo '%sudo ALL=(ALL) NOPASSWD:ALL' >> /etc/sudoers
  
  RUN printf '\nexport LANG="C"\nexport LANGUAGE="C"\nexport LC_ALL="C"\n' >> "/home/${USERNAME}/.bashrc"

• devcontainer.json

  {
      "name": "LilyPond",
      "build": {
          "dockerfile": "Dockerfile",
          // Update 'VARIANT' to pick an LilyPond version: 2.22.0, 2.23.0, etc.
          "args": { "VARIANT": "devel-fonts" }
      },
      // Add the IDs of extensions you want installed when the container is created.
      "extensions": [
          "lhl2617.vslilypond",
          "tomoki1207.pdf"
      ],
      // Connect as a non-root user. See https://aka.ms/vscode-remote/containers/non-root.
      "remoteUser": "vscode"
  }

Do you have any idea how to make it work?

[lhl2617]

There is something fishy about Linux and timidity that I haven't had the time to look into -- please refer to #173 and see if that works? Happy to try running this dev container when I have time as per your other issue.

Thanks for reporting this!

[jeandeaual]

Thanks for the info. Unfortunately I didn't manage to make the MIDI player nor the MIDI input feature on Linux.
I'll take a look again when I have some more free time.

Meanwhile, here is the dev container I use when working on LilyPond projects.

[lhl2617]

Sorry for putting this off for so long--I'm looking into this now

[lhl2617]

Hmm -- the whole devcontainer crashed for me when I tried any MIDI action from the extension

Is this what you see as well? @jeandeaual

[lhl2617]

Opened https://github.com/microsoft/vscode/issues/123836 -- it is rather annoying to debug without any logs/trace

[lhl2617]

This problem seems to stem from the JZZ() call failing on Docker/WSL2 envs. Will set up a repro repo and open an issue in jzz

[lhl2617]

@jeandeaual -- what is your host machine's OS?

[lhl2617]

Opened jazz-soft/JZZ#43 for jzz failing on WSL2

[lhl2617]

Opened jazz-soft/JZZ#43 for jzz failing on WSL2

Fixed via jazz-midi 1.7.5; waiting for JZZ and jzz-midi-smf deps to be updated.

[lhl2617]

Can confirm that release 1.6.4 (#255) does not crash VSCode. However, it implies it is playing/recording even without any device present. 1.6.5 (#257) will add a fix to crash when no (in|out)puts are found

[lhl2617]

The crashing behavior is fixed in #257

I doubt MIDI playback/input can actually be done reliably in a devcontainer, but at least now it does not crash when the MIDI buttons are pressed.

Relevant:
https://stackoverflow.com/questions/65912601/docker-container-as-midi-io-device

[lhl2617]

Reopening until we can have MIDI IO via docker (if that's at all possible)

[lhl2617]

https://stackoverflow.com/a/41084959/9723640 -- it might be possible to forward audio out of a container--I've done this with PulseAudio with WSL2.

The container would need to mount /dev/snd--I'll come back when I have time.

[jeandeaual]

@lhl2617 Sorry I didn't get back to you earlier, and thanks for investigating this issue!

@jeandeaual -- what is your host machine's OS?

I tested on Windows 10 (x64), Arch Linux (x64) and macOS Big Sur (Apple M1).

https://stackoverflow.com/a/41084959/9723640 -- it might be possible to forward audio out of a container--I've done this with PulseAudio with WSL2.

The container would need to mount /dev/snd--I'll come back when I have time.

I tried again after uncommenting this line:

• Windows 10 doesn't seem to work yet (maybe due to Block devices, (i.e. /dev/sda) ? microsoft/WSL#689)
• On Linux I got No sound devices found even though it works fine on the host
• On macOS I got [2021-06-14T15:36:27.974Z] docker: Error response from daemon: error gathering device information while adding custom device "/dev/snd": no such file or directory.

This is a minor inconvenience, but it'd be nice if all VSLilyPond features worked inside containers.

[lhl2617]

but it'd be nice if all VSLilyPond features worked inside containers.

I agree--I think overall piping audio out from a container into the host system is a challenge; however, I'll look into it deeper.

I currently only have a Ubuntu 20.04 (x64) and Win10 (x64) machine. I am able to replicate the Windows 10 behaviour--I assume on Ubuntu it would be as you observed on Arch. I will soon obtain whatever 16 inch device comes with Apple silicon to test.

Thanks so much for testing this!