Arm64 support

[darylrobbins]

#51

Summary

Build arm64 images for all stacks. Unfortunately, Github Actions does not currently support arm64 workers, but I have tested locally.

Use Cases

Running on arm64.

Checklist

• I have viewed, signed, and submitted the Contributor License Agreement.
• I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• I have added an integration test, if necessary. (not supported by Github Actions today)
• I have reviewed the styleguide for guidance on my code quality.
• I'm happy with the commit history on this PR (I have rebased/squashed as needed).

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Daryl Robbins (13e6997)

[sophiewigmore]

@darylrobbins thank you for your contribution! I'll check it out and see what next steps are. I would imagine we will need an RFC to formally propose supporting the ARM64 stack, and codify what will be needed. Also tagging @dmikusa-pivotal and @ryanmoran here as well.

[dmikusa]

This is awesome, thanks!

+1 for an RFC. I think that would give us a chance to pull together a list of all the pieces that would need to be modified and create a plan on how we move forward together so that we can claim ARM64 support. The individual language teams can then use that to make sure they're following the right path.

[sophiewigmore]

@darylrobbins looking through your changes I don't see many test updates. Is it possible to add some to our acceptance tests if possible / any of the create-stack tests?

[darylrobbins]

I can create them but not sure how we'll be able to run them as part of the pipeline without an arm64 build agent.

[sophiewigmore]

Ah true. I worry about eventually publishing and supporting stacks that we can't test first in a public-facing manner

[darylrobbins]

@sophiewigmore Is there any possibility of setting up a self-hosted runner for the project that runs on arm64? GitHub Actions does support arm64 for self-hosted runners.

[sophiewigmore]

According to https://github.blog/changelog/2019-12-03-github-actions-self-hosted-runners-on-arm-architectures/ we should be able to set something up.. Although this is the first time I've ever looked into it. The Cloud Native Buildpacks project has some stuff set up here through Equinix Metal we might be able to leverage

[robdimsdale]

We are going to archive this repo so we will close this issue.

Supporting arm architectures is on our roadmap. We have also extracted the create-stack code from this repo into a new jam create-stack command (see here), so that's where any future changes will go.