Update Python packaging approach to `pyproject.toml`

[jenstroeger]

Is your feature request related to a problem? Please describe.

After looking through .circleci/packaging/python, it seems to me that the Python package uses the somewhat dated setup.py approach. There’s much discussion to remove it from the documentation and to guide packages in migrating to myproject.toml (PEP 631). (Also note that according to this announcement the support for setup.py will be removed from Python 3.12 internal packages.)

Describe the solution you'd like

It shouldn’t be too difficult to migrate and to follow the updated packaging guidelines, and move the package forward to the new approach.

Describe alternatives you've considered

Nope.

Additional context

Looking at the current setup.py I don’t see a minimum Python version specified although the classifiers indicate that support for Python 2.7 is required (the classifiers are incomplete too). However, there’s a second repository googleapis/python-api-common-protos whose content is generated from this repository? There too, setup.py should be replaced.

I’m not sure which one of the repositories is the base…

[Lawouach]

Hi,

This is indeed a bit of an issue that this lib isn't modernized to match where the Python Packaging ecosystem is going. It does leave warnings when deployed with tools such as PDM.

[chalmerlowe]

I don't know if it is still a concern, but at one point even if you switched to pyproject.toml there was a requirement to provide a shim in setup.py if you wanted to be able to install a package in editable mode (i.e. using pip install -e):

#!/usr/bin/env python

import setuptools

if __name__ == "__main__":
    setuptools.setup()

[jenstroeger]

@chalmerlowe that shouldn’t be an issue anymore, see here.

[parthea]

This feature is still in the backlog. We are preparing to migrate the code in this repository to google-cloud-python. I'm going to close this as a duplicate of googleapis/google-cloud-python#13171 which is to track the upgrade for the entire repository.