github: Replace Gr1N/setup-poetry with a composite action that supports caching

[bkeryan]

• This contribution adheres to CONTRIBUTING.md.

What does this Pull Request accomplish?

Create a composite action wrapper for setup-python:

• Single-source default Python version

Replace https://github.com/Gr1N/setup-poetry with a composite action, setup-poetry:

• Single-source default Poetry version
• Install Poetry manually. I originally implemented this using pipx, but ran into three problems:
  • GitHub-hosted runners have pipx installed in /opt/pipx and C:\Program Files (x86)\pipx, which cannot be overwritten by actions/cache. The workaround for this is to set PIPX_HOME and PIPX_BIN_DIR.
  • pipx on Windows was trying to use the py launcher, but I think this was a side effect of mixing up / and \ in my environment variables.
  • The pipx dir is a shared resource, and caching it in this action will do the wrong thing if the workflow uses pipx to install other Python commands. Installing Poetry manually allows us to keep it completely isolated, for caching purposes. The downside is that we have to deal with venv/bin vs. venv/Scripts and create our own symlinks.
• Specify the Python version for Poetry so we don't have to do poetry env use python
• Cache the Poetyr bin/home directories to speed up workflows

Why should this Pull Request be merged?

This week's Poetry + virtualenv problems have me thinking about Poetry install reproducibility.

• https://github.com/Gr1N/setup-poetry fetches the install script from https://install.python-poetry.org/ every time you run it and doesn't provide a way to override transitive dependencies.
• pipx allows overriding transitive dependencies with pipx inject.
• https://github.com/Gr1N/setup-poetry is the slowest part of this repo's workflows and I have wanted to enable caching for the Poetry install.

What testing has been done?

Many, many, PR builds

[github-actions]

Test Results

   10 files  ±0     10 suites  ±0   28s ⏱️ -2s
  573 tests ±0    573 ✅ ±0  0 💤 ±0  0 ❌ ±0 
5 730 runs  ±0  5 730 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit 3e9a167. ± Comparison against base commit 13cbe86.

♻️ This comment has been updated with latest results.

[bkeryan]

@mshafer-NI Do you have any feedback on this?

I would like to start using this approach in nidaqmx-python, measurement-plugin-python, ni-apis, etc.

Perhaps this composite action should be single-sourced in its own repo, or a repo for shared actions like an ni-github-actions or ni-python-actions.

I'm also considering splitting out the call to setup-python. I think we can figure this out without passing step outputs.

[bkeryan]

What is the impact of caching the Poetry install? Let's compare https://github.com/ni/nitypes-python/actions/runs/14934916371 to https://github.com/ni/nitypes-python/actions/runs/14948460939/job/41994856909?pr=28.

• The overall workflow duration went from 4 minutes to 2 minutes.
• The Run unit tests (Windows) durations went from 1-2 minutes to 25-27 seconds.

[bkeryan]

setup-python sets the pythonLocation environment variable, so we don't really need to combine these actions.

[mshafer-NI]

(approve with the suggestion that we "standardize" these)

[mshafer-NI]

proposal: we move this into a "ni/gh-actions" repo

[mshafer-NI]

proposal: we move this into a "ni/gh-actions" repo

[mshafer-NI]

Would it be possible to have Renovate auto-update this??

[mshafer-NI]

Can Renovate auto-update this?

[bkeryan]

Yes, it can even convert @v4 to this format:
https://docs.renovatebot.com/presets-helpers/#helperspingithubactiondigeststosemver

[bkeryan]

I moved these actions to https://github.com/ni/python-actions/ and updated this repo to use them in #30