conda-forge release

[tsrobinson]

We should look to write the files needed to also publish on conda-forge.

A basic guide is here: https://levelup.gitconnected.com/publishing-your-python-package-on-conda-and-conda-forge-309a405740cf

Steps:

• [ ] Check that all our dependencies (and min. versions) are on conda-forge
• [ ] Figure out if we can have both PyPI and Conda yamls in the same repo (I assume we can)
• [ ] Setup GitHub action to automatically release to conda-forge when we release to PyPI

[tsrobinson]

Re. automatic release, my brief search suggests this sound like a bit of a headache. Seems like some tools help with automation (e.g. grayskull) but that to fully automate you would need an action to commit to a new branch of the conda-forge feedstock, then pull request it.

[tsrobinson]

Following on from our offline discussions @ayn2, seems like we can use grayskull but that there are some tricky issues to overcome, which I suspect are related to us using the flit build system.

I had another brief search and found a package that is both a) published on conda-forge, and b) uses flit as their PyPI build

The main repo is here: https://github.com/sparks-baird/mat_discover

Note: this project doesn't keep the meta.yaml file. Instead, as part of the build action, it temporarily creates it using grayskull, amends it, and then pushes it via a GitHub action server (which we should also do).

With that in mind, these files may be worth checking over:

• pyproject.toml -- this looks very similar to ours atm
• run_grayskull.py -- this is how they create and then edit the conda-forge recipe stuff -- we might not need all of this, but some of it may be instructive
• Full test, publish, release action -- we have something similar, but this contains the conda forge stuff too

Any questions, let me know!

[tsrobinson]

I got it to work, and this is now under review with the conda forge team!

The main sticking issues were a) the conda version of flit is flit-core compared to the base flit_core, and b) datetime was an unnecessary requirement (resolved in v0.0.10)