shrub/pkg/docker-image
Edward Amsden a64e0e141e
build: Build docker image and publish to Docker Hub
d3c5aa74c1 introduced a Docker image intended for deploying Urbit ships

This commit modifies the build.yml GitHub Actions workflow to build the
docker image as part of the push/PR workflow, and adds a
`release-docker.yml` workflow, which runs on any tag push `urbit-v*` and
pushes the image to Docker Hub, also synchronizing the README.

Co-authored-by: Josh Lehman <josh@urbit.org>
2021-01-13 12:36:45 -05:00
..
README.md build: Build docker image and publish to Docker Hub 2021-01-13 12:36:45 -05:00

Official Urbit Docker Image

This is the official Docker image for Urbit.

Urbit is a clean-slate OS and network for the 21st century.

Using

To use this image, you should mount a volume with a keyfile, comet file, or existing pier at /urbit, and map ports as described below.

Volume Mount

This image expects a volume mounted at /urbit. This volume should initially contain one of

  • A keyfile <shipname>.key for a galaxy, star, planet, or moon. See the setup instructions for Urbit for information on obtaining a keyfile.
    • e.g. sampel-palnet.key for the planet sampel-palnet.
  • An empty file with the extension .comet. This will cause Urbit to boot a comet in a pier named for the .comet file (less the extension).
    • e.g. starting with an empty file my-urbit-bot.comet will result in Urbit booting a comet into the pier my-urbit-bot under your volume.
  • An existing pier as a directory <shipname>. You can migrate an existing ship to a new docker container in this way by placing its pier under the volume.
    • e.g. if your ship is sampel-palnet then you likely have a directory sampel-palnet whose path you pass to ./urbit when starting. Move your pier directory to the volume and then start the container.

The first two options result in Urbit attempting to boot either the ship named by the name of the keyfile, or a comet. In both cases, after that boot is successful, the .key or .comet file will be removed from the volume and the pier will take its place.

In consequence, it is safe to remove the container and start a new container which mounts the same volume, e.g. to upgrade the version of the urbit binary by running a later container version. It is also possible to stop the container and then move the pier away e.g. to a location where you will run it directly with the Urbit binary.

Ports

The image includes EXPOSE directives for TCP port 80 and UDP port 34343. Port 80 is used for Urbit's HTTP interface for both Landscape and for API calls to the ship. Port 34343 is used by Ames for ship-to-ship communication.

You can either pass the -P flag to docker to map ports directly to the corresponding ports on the host, or map them individually with -p flags. For local testing the latter is often convenient, for instance to remap port 80 to an unprivileged port.

Extending

You likely do not want to extend this image. External applications which interact with Urbit do so primarily via an HTTP API, which should be exposed as described above. For containerized applications using Urbit, it is more appropriate to use a container orchestration service such as Docker Compose or Kubernetes to run Urbit alongside other containers which will interface with its API.

Development

The docker image is built by a Nix derivation in the nix/pkgs/docker-image/default.nix file under the Urbit git repository.