anki/docs/docker

Building and running Anki in Docker

This is an example Dockerfile contributed by an Anki user, which shows how Anki can be both built and run from within a container. It works by streaming the GUI over an X11 socket.

Building and running Anki within a container has the advantage of fully isolating the build products and runtime dependencies from the rest of your system, but it is a somewhat niche approach, with some downsides such as an inability to display natively on Wayland, and a lack of integration with desktop icons/filetypes. But even if you do not use this Dockerfile as-is, you may find it useful as a reference.

Anki's Linux CI runs on GitHub Actions. You can use, as references, the setup-anki to see the lists of packages CI installs, and ci.yml to see the build steps that follow.

Build the Docker image

For best results, enable BuildKit (export DOCKER_BUILDKIT=1).

When in this current directory, one can build the Docker image like this:

docker build --tag anki --file Dockerfile ../../

When this is done, run docker image ls to see that the image has been created.

If one wants to build from the project's root directory, use this command:

docker build --tag anki --file docs/docker/Dockerfile .

Run the Docker image

Anki starts a graphical user interface, and this requires some extra setup on the user's end. These instructions were tested on Linux (Debian 11) and will have to be adapted for other operating systems.

To allow the Docker container to pull up a graphical user interface, we need to run the following:

xhost +local:root

Once done using Anki, undo this with

xhost -local:root

Then, we will construct our docker run command:

docker run --rm -it \
    --name anki \
    --volume $HOME/.local/share:$HOME/.local/share:rw \
    --volume /etc/passwd:/etc/passwd:ro \
    --user $(id -u):$(id -g) \
    --volume /tmp/.X11-unix:/tmp/.X11-unix:rw \
    --env DISPLAY=$DISPLAY \
    anki

Here is a breakdown of some of the arguments:

• Mount the current user's ~/.local/share directory onto the container. Anki saves things into this directory, and if we don't mount it, we will lose any changes once the container exits. We mount this as read-write (rw) because we want to make changes here.

  --volume $HOME/.local/share:$HOME/.local/share:rw
  

• Mount /etc/passwd so we can enter the container as ourselves. We mount this as read-only because we definitely do not want to modify this.

  --volume /etc/passwd:/etc/passwd:ro
  

• Enter the container with our user ID and group ID, so we stay as ourselves.

  --user $(id -u):$(id -g)
  

• Mount the X11 directory that allows us to open displays.

  --volume /tmp/.X11-unix:/tmp/.X11-unix:rw
  

• Pass the DISPLAY variable to the container, so it knows where to display graphics.

  --env DISPLAY=$DISPLAY
  

Running Dockerized Anki easily from the command line

One can create a shell function that executes the docker run command. Then one can simply run anki on the command line, and Anki will open in Docker. Make sure to change the image name to whatever you used when building Anki.

anki() {
    docker run --rm -it \
        --name anki \
        --volume $HOME/.local/share:$HOME/.local/share:rw \
        --volume /etc/passwd:/etc/passwd:ro \
        --user $(id -u):$(id -g) \
        --volume /tmp/.X11-unix:/tmp/.X11-unix:rw \
        --env DISPLAY=$DISPLAY \
        anki "$@"
}