Publish an sdist on PyPI

[jayvdb]

Overview of issue:

PyPI only currently has wheels. i.e. https://pypi.org/project/apigentools/#files

These are not suitable for using with packaging tools.

Also it is not easy to use github tarballs as an alternative, as the following error occurs:

[   17s] + /usr/bin/python3.8 setup.py build '--executable=/usr/bin/python3.8 -s'
[   17s] Traceback (most recent call last):
[   17s]   File "setup.py", line 27, in <module>
[   17s]     setup(
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools/__init__.py", line 87, in setup
[   17s]     return distutils.core.setup(**attrs)
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools/_distutils/core.py", line 139, in setup
[   17s]     _setup_distribution = dist = klass(attrs)
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools/dist.py", line 476, in __init__
[   17s]     _Distribution.__init__(
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools/_distutils/dist.py", line 275, in __init__
[   17s]     self.finalize_options()
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools/dist.py", line 900, in finalize_options
[   17s]     ep(self)
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools/dist.py", line 920, in _finalize_setup_keywords
[   17s]     ep.load()(self, ep.name, value)
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools_scm/integration.py", line 75, in version_keyword
[   17s]     _assign_version(dist, config)
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools_scm/integration.py", line 51, in _assign_version
[   17s]     _version_missing(config)
[   17s]   File "/usr/lib/python3.8/site-packages/setuptools_scm/__init__.py", line 106, in _version_missing
[   17s]     raise LookupError(
[   17s] LookupError: setuptools-scm was unable to detect version for /home/abuild/rpmbuild/BUILD/apigentools-1.6.4.
[   17s] 
[   17s] Make sure you're either building from a fully intact git repository or PyPI tarballs. Most other sources (such as GitHub's tarballs, a git checkout without the .git folder) don't contain the necessary metadata and will not work.
[   17s] 
[   17s] For example, if you're using pip, instead of https://github.com/user/proj/archive/master.zip use git+https://github.com/user/proj.git#egg=proj

That suggestion doesnt work when building a package in an offline VM to ensure proper build isolation.

[github-actions]

Thanks for your contribution!

This issue has been automatically marked as stale because it has not had activity in the last 30 days. Note that the issue will not be automatically closed, but this notification will remind us to investigate why there's been inactivity. Thank you for participating in the Datadog open source community.

If you would like this issue to remain open:

1. Verify that you can still reproduce the issue in the latest version of this project.

2. Comment that the issue is still reproducible and include updated details requested in the issue template.

[jayvdb]

Latest release on PyPI hasnt addressed this.