Add docker support

[cyberbit]

Here is a Dockerfile I got working, supporting compose and run. It launches the binary through supervisor to manage any unhandled crashes. The compose file points to my own published image at the moment (https://hub.docker.com/r/cyberbit/satpaper), but replacing image: cyberbit/satpaper with build: . allows building the image locally.

The final image from Docker Hub is around 30 MB compressed, or ~1.5 Satpaper cycles.

[Colonial-Dev]

I like the idea, but I just want to check something first - what's the maintenance burden on a Docker config? I'm pretty sure it's basically nothing, but Docker isn't really my forte and I want to know what I'm getting myself into :p

Also, would it be possible to put everything into a docker/ subdir? I have a bad feeling that people will skim the file list and think it only supports Docker or something 😅

[cyberbit]

what's the maintenance burden on a Docker config?

As you say, basically nothing. I have built this out as an Alpine Linux image, so as long as satpaper continues to support Linux it should Just Work™️. If it does require a libfoo in the future, it can be added to the Dockerfile trivially via apk at build time.

A Docker build is something that can be done via Actions as well, so I will take some time to put together that too. I also realize now you have tests prepared, so I will update the build to check those before the image is packaged.

would it be possible to put everything into a docker/ subdir?

Yes, I'll update the PR.

[cyberbit]

PR updated:

• Moved tooling to docker/
• Added build-docker to the Cargo Comprehensive action. This runs the minimum necessary for cargo test --release within Docker.

An automatic Docker Hub release can be done (https://docs.docker.com/build/ci/github-actions/push-multi-registries/) but if you don't want to do a Docker Hub account, I can keep my published fork updated to the best of my ability.

[Colonial-Dev]

Thanks for the contribution! And yeah, probably best for you to do the Docker Hub upkeep :p