READTHEDOCS_VERSION_TYPE env variable support removed

[jsquyres]

Details

• Read the Docs project URL: https://readthedocs.org/projects/ompi/
• Build URL (if applicable): https://readthedocs.org/projects/ompi/builds/16504880/
• Read the Docs username (if applicable): https://readthedocs.org/profiles/jsquyres/

Expected Result

As documented at https://docs.readthedocs.io/en/stable/builds.html#build-environment, the environment variable READTHEDOCS_VERSION_TYPE is supposed to exist in the RTD Github CI build environment.

Since it is documented, we use this environment variable in our project's conf.py file. It has been working fine until today.

Actual Result

This environment variable was present on an RTD Github CI build around 1pm US Eastern today (29 Mar 2022): https://readthedocs.org/projects/ompi/builds/16504767/

But about 15 minutes later, this environment variable was no longer in the RTD Github CI build environment (at about 1:11pm US Eastern 29 Mar 2022), resulting in a KeyError Python error from our conf.py file when we try to access os.environ['READTHEDOCS_VERSION_TYPE']: https://readthedocs.org/projects/ompi/builds/16504880/

Looking at the git history in this repo, it looks like the READTHEDOCS_VERSION_TYPE functionality was introduced in PR #8237. But later, when PR #9002 was merged, it looks like at least part of #8237 was (unintentionally?) reverted.

Specifically, it looks like get_rtd_env_vars() was moved from here to here, but the new env variables from #8237 were not carried over.

Can READTHEDOCS_VERSION_TYPE functionality be restored?

Thanks for ReadTheDocs.io!

[jsquyres]

Fixed via #9052. Hopefully to be deployed to production later today.