BLD: PEP518/pyproject.toml todo items

[tylerjereddy]

Irfan is planning a release soon, and if we do plan to upload a source distribution to PyPI for that release we may want to add a few things to pyproject.toml beyond the initial draft in gh-3398. If issues with that file do pop up please ping me directly (@) so I see the notification on my phone (a few too many GitHub emails to scan these days..).

• add a [project] section with some useful metadata (can mimic other popular Python projects for this most likely)
  • name
  • license
  • maintainers
  • requires-python
  • dependencies (this means "runtime" instead of "buildtime" I think, but just for metadata as I understand it, at least for pip)
  • readme (path to readme file I think)
  • classifiers (the PyPI homepage for the release will extract a bunch of metadata from here like supported operating systems, and the versions of Python we consider supported)
• [project.optional-dependencies] section
  • optional testing deps
  • optional doc building deps
  • optional development tools/linters, etc.
• [project.urls] for homepage, source repo, etc.

[IAlibay]

So how much of this is currently getting picked up from what's in our setup.py? I notice that most of the classifiers are already on our pypi page, is it just a case of moving things from setup.py over to the pyproject.toml?

[tylerjereddy]

Yeah, and it looks like some important Python projects are currently opting to keep the copies in both files for now. I actually don't know if there is an order of precedence on the metadata extraction--not exactly an exciting thing to look into, Google might tell us.

I suspect if we're lazy for now the setup.py may continue to provide what it did before, but not 100 % sure.

[IAlibay]

We can add it all to pyproject.toml, keep setup as-is and then see what testpypi does? Worse case scenario we just have to rollback a few things.