Provide a Docker image and instructions how to use it

[colindean]

I don't do much Ruby these days but I've got a whole lot of projects I built 2010-2019 that use "the Ruby version as of the day I started" for the most part and I've only upgraded when necessary. Bad maintainer or busy maintainer, I don't know.

I'd love to be able to do

docker run --rm -it -e GITHUB_TOKEN="${GITHUB_TOKEN}" matheusrich/end_of_life:latest

and get a report. That could even turn into a cronjob on my containers server or a GitHub Action or something.

[MatheusRich]

Sounds good! My Docker skills are rusty, but I might take a stab at it.

[colindean]

I've got it ~working with as little as

FROM ruby:3-alpine

RUN gem install end_of_life

CMD ["end_of_life"]

but #10 has to go through first because the JSON end of life data path isn't valid when installing from Rubygems, apparently.

Now, that Dockerfile would just install the latest from Rubygems, which would be OK if the steps before it pushed the gem. It's probably better to install the gem GHA just built with something like this:

FROM ruby:3-alpine

COPY ./end_of_life*.gem .

RUN gem install end_of_life*.gem && rm end_of_life*.gem

CMD ["end_of_life"]

https://github.com/marketplace/actions/build-and-push-docker-images is a starting point for that. I'm out of time for now!