Spack Build Cache (with GitHub) Demo

This is a small demo to show how you can derive an entire spack build cache on GitHub pages / workflows / packages and then integrate with spack. While conceptually simply to integrate, the actual integration will require refactoring how mirrors work (note that it's currently hard coded with S3) so I opted for a demo.

GitHub Packages Build Cache

Read all about that at autamus/spack-build-cache.

TLDR: a bunch of workflows use actions from vsoch/spack-package-action to create a matrix of packages, install them, add them to a build cache, deploy to GitHub packages, and deploy a web interface alongside to explore. Here is the example interface for the autamus build cache.

Usage

The demo is fairly easy to run! Make sure you have spack on your path, and then:

$ spack python run-demo.py 
==> Warning: Mirror with name autamus-github already exists.
==> Preparing to download ghcr.io/autamus/spack-build-cache/21.11/build_cache/linux-ubuntu20.04-broadwell-gcc-10.3.0-ncurses-6.2-76gsydzye33lca3iqhfijgaxiq46ga53.spack
==> Fetching oras ghcr.io/autamus/spack-build-cache/21.11/build_cache/linux-ubuntu20.04-broadwell-gcc-10.3.0-ncurses-6.2-76gsydzye33lca3iqhfijgaxiq46ga53.spack
==> pull ghcr.io/autamus/spack-build-cache/21.11/build_cache/linux-ubuntu20.04-broadwell-gcc-10.3.0-ncurses-6.2-76gsydzye33lca3iqhfijgaxiq46ga53.spack:latest --output /home/vanessa/Desktop/Code/spack-build-cache-poc
Downloaded 257c65fda48e linux-ubuntu20.04-broadwell-gcc-10.3.0-ncurses-6.2-76gsydzye33lca3iqhfijgaxiq46ga53.spack
Pulled ghcr.io/autamus/spack-build-cache/21.11/build_cache/linux-ubuntu20.04-broadwell-gcc-10.3.0-ncurses-6.2-76gsydzye33lca3iqhfijgaxiq46ga53.spack:latest
Digest: sha256:f57f32693ae091ad69c8b65b8a79b67c50d430ecb9f1b403a5ca6e36760296d9

And then the matching binary is in your present working directory. In actual spack this would be called by a fetched in the Stage class, which sploots it where it needs to be.

$ ls
linux-ubuntu20.04-broadwell-gcc-10.3.0-ncurses-6.2-76gsydzye33lca3iqhfijgaxiq46ga53.spack  mirror.py  mirrors  __pycache__  README.md  run-demo.py

So, if this looks interesting to you, please use the run-demo.py and example mirrors module and mirror.py class to integrate into spack!