python: too many libraries are being released

[jskeet]

Migration has modified the README.md files and .repo-metadata.md files of almost all libraries. We have put configuration in place to try to avoid those (unimportant) changes prompting a release, but it looks like this has been ineffective. A bulk release run created googleapis/google-cloud-python#16901 for example.

We should investigate why libraries with no code changes are being re-released.

[jskeet]

Running legacylibrarian release stage locally:

• With no changes, 259 packages are released
• Adding packages/{pkg}/README.md to the release exclusion list reduces this to 175 - but that's still a lot

Investigating further...

[jskeet]

Changing the exclusion of packages/{pkg}/docs/README.md to packages/{pkg}/docs/ reduces this to 64, which sounds a lot more plausible.

Adding noxfile.py and tests/ reduces this to 51. At that point I think we've reached the point of diminishing returns.

So an entry in .librarian/state.yaml would look something like this:

    release_exclude_paths:
      - packages/google-cloud-kms/.repo-metadata.json
      - packages/google-cloud-kms/noxfile.py
      - packages/google-cloud-kms/tests/
      - packages/google-cloud-kms/README.rst
      - packages/google-cloud-kms/docs/

Will check this with the Python team.

[suztomo]

I recently touched the logic to ignore certain files for releases (#5404).

[jskeet]

@suztomo: I'm confused by the description of that PR, as I didn't know legacylibrarian used librarian.yaml at all. The above change definitely does work (or did 7 hours ago) because I tested it with that. Of course, we should figure out what we'll do when we move off legacylibrarian for Python, but I'd expect us to just use .librarian/state.yaml until then, so config.Release.IgnoredChanges is irrelevant. (That PR doesn't touch any files under legacylibrarian, for one thing.) Could you clarify things or correct me?

[suztomo]

Ok. As it was working 7 hours ago, then my change is irrelevant to legacylibrarian. Good.

[jskeet]

Closing now that the two relevant PRs have been merged.