Plan for antsibull-core v3

[gotmax23]

I created a milestone and have started creating issues to track antsibull-core v3. My impetus for starting up this effort is wanting to add support for pydantic v2, but there's also a good amount deprecated code to remove. @felixfontein, what do you think about the following plan?

For antsibull-core v3, I'd like to completely drop support for pydantic v1 and stick to pydantic v2. antsibull-core v2 can stick to pydantic v3. Maintaining compatibility for both is a bit tricky, and parts of the pydantic API that are exposed/used by antsibull-core as part of the LibContext and AppContext objects are changing in a backwards compatible way, so we would probably want to add support in a new major release anyways.

We might consider dropping support for Python 3.9, as well, to allow us to adopt newer typing features and other improvements. ansible-core has already dropped support for Python 3.9 on the controller.

antsibull and antsibull-docs can keep concurrent support for both antsibull-core v2 and v3 for a little while, like we did for antsibull-core v1. I'm not sure about when we'd want to cut a antsibull-docs v3 release to drop support for antsibull-core v2. antsibull-docs is more your area than mine.

I think I'll be able to write some compat code for antsibull-docs to remain compatible with both pydantic versions (and thus both antsibull-core versions). I already submitted ansible-community/antsibull-build#564 for antsibull. It uses LibContext and AppContext but doesn't have its own pydantic models, so that was easier.

[felixfontein]

For antsibull-core v3, I'd like to completely drop support for pydantic v1 and stick to pydantic v2. antsibull-core v2 can stick to pydantic v3. Maintaining compatibility for both is a bit tricky, and parts of the pydantic API that are exposed/used by antsibull-core as part of the LibContext and AppContext objects are changing in a backwards compatible way, so we would probably want to add support in a new major release anyways.

Sounds good to me!

We might consider dropping support for Python 3.9, as well, to allow us to adopt newer typing features and other improvements. ansible-core has already dropped support for Python 3.9 on the controller.

I'm not so sure about that one. antsibull-docs should likely support Python 3.9 for some longer time. Dropping Python 3.9 support for antsibull-core v3 forces antsibull-docs to support both antsibull-core v2 and v3 for a longer time.

(The last ansible-core version to support Python 3.9 is EOL in November 2024.)

antsibull and antsibull-docs can keep concurrent support for both antsibull-core v2 and v3 for a little while, like we did for antsibull-core v1. I'm not sure about when we'd want to cut a antsibull-docs v3 release to drop support for antsibull-core v2. antsibull-docs is more your area than mine.

That depends on what happens to Python 3.9 support. I don't mind getting rid of antsibull-core v2 support sooner than later, but if that requires to drop Python 3.9 support it's not an option.

[gotmax23]

Yeah, I'm fine with keeping Python 3.9 support for antsibull-core v3. I just put that option out there.

I think I'll be able to write some compat code for antsibull-docs to remain compatible with both pydantic versions (and thus both antsibull-core versions). I already submitted ansible-community/antsibull#564 for antsibull. It uses LibContext and AppContext but doesn't have its own pydantic models, so that was easier.

I submitted ansible-community/antsibull-docs#224. I changed everything to use the pydantic.v1 compat module (which is just a copy of the last pydantic v1 release included within pydantic v2's tree) for all models except AppContext which is inherited from antsibull-core. It's a bit messy and touches several files. I'd really prefer not to do this and just keep antsibull-docs v2 tied to antsibull-core v2 and properly port antsibull-docs v3 to pydantic v2, but I just wanted to put this out there.

What do you think?

[felixfontein]

Sounds good to me!

[gotmax23]

@felixfontein, you mean

keep antsibull-docs v2 tied to antsibull-core v2 and properly port antsibull-docs v3 to pydantic v2

or that we should attempt to maintain compatibility between antsibull-docs v2 and antsibull-core v3 as in ansible-community/antsibull-docs#224?

[felixfontein]

Ah sorry, yes, I meant making it compatible to both core v2 and v3. I'd lke to avoid doing a new major release for some time...

[gotmax23]

I created a stable-2 branch and filed the following PRs:

• Adjust CI for antsibull-core v3 antsibull-build#567
• Adjust CI for antsibull-core v3 antsibull-docs#230
• Set up antsibull-core v3 development #127

[gotmax23]

@felixfontein, what do you think about creating a 3.0.0a1 release later this week?

[felixfontein]

@gotmax23 sounds good to me! If you have time, can you take a look at #135? Would be nice to get that one in as well.

[gotmax23]

We can cut the release after #144 is reviewed and merged.

[felixfontein]

So, how should we proceed? Should we do 3.0.0 final soon?

[gotmax23]

Yes, I think so!

[felixfontein]

antsibull-core 3.0.0 is out! \o/ The remaining task is to eventually limit the minimum antsibull and antsibull-docs versions supporting 3.0.0 in CI; I've created #154 to track this.