GitHub Action for Update Checking

[natescherer]

Hi All,
Now that the check-update subcommand has been merged to main, I wanted to start a discussion thread around making a GitHub Action for easily checking if there are updates to the template your project uses.

I am perfectly happy with writing and maintaining this action on my own, but I wanted to throw a discussion out there in case there was interest in having this action adopted by copier-org.

For those unfamiliar with GitHub actions, there are four main ways you can do it:

1. Javascript-based
   • Powerful, but unnecessarily complex for this use case, and requires updates every so often to track Node versions
2. Composite, using bash
   • Good for many use cases, but less so here since the action needs to parse JSON and there's no native JSON support in Bash, adding an additional requirement for a tool like jq or yq
3. Composite, using PowerShell
   • PowerShell has built in JSON support and is part of every Microsoft-official runner image
4. Docker-based
   • Only supports Linux runners, which I consider a non-starter

For the reasons I laid out above, I plan on going with option 3 if I am developing this on my own, but am open to refactoring if the maintainers want this to be part of copier-org. On that note: per GitHub's recommendations this should be its own repo, so we'd be looking at something like copier-org/github-action-copier.

I'll be starting work on this as soon as a release is cut that includes #2463, but will wait to publish to GitHub Marketplace until the maintainers chime in.

Thanks, all!

[sisp]

Thanks for starting this discussion, @natescherer! 👍 I'm generally open to having a GitHub Action repo in the copier-org organization. I haven't built any GHAs yet, so I might be missing something: How about creating a composite action using a Python "shell"? Copier requires Python anyway, and Python supports JSON parsing – among lots of other things – via the standard library. Is this an option to keep it simple yet avoid Microsoft-only tooling?

[natescherer]

That's a great call actually. I usually avoid using a non-shell language to do logic in a composite action (to avoid additional deps) but, naturally, we have to install/use Python to run copier. I will experiment along these lines and comment back when I have something working in my test repo!

[natescherer]

Okay @sisp, I've got this ready at https://github.com/natescherer/copier-action. I raised several issues with design choices I wanted to bring up, discussion about what adopting it into copier-org would look like, etc. Feel free to open additional issues if there are other things to discuss, seems easier to discuss there than here.