Breaking change policy

[azeey]

Changes to messages are usually breaking changes and so, should only be done in the main/rolling branch, especially after a package has reached 1.0.0. (see https://docs.ros.org/en/kilted/The-ROS2-Project/Contributing/Developer-Guide.html#versioning). To align ourselves with ROS best practices on branching, we should create a branch for each ROS distro and make releases out of them. We can then limit backports to non-breaking changes.

[zakmat]

Thanks for raising this!

Unaware of this specific guideline I have already released 2.0.0 into humble, jazzy and kilted. It is awaiting next sync. What's the best course of action? I could create a PR that reverts ros/rosdistro#47106, ros/rosdistro#47107 and ros/rosdistro#47108 Would that solve the issue, or are there any extra steps?

I think the breaking part of the worlds functionality was only related to the introduction of Resource msg in the existing interfaces - back-porting is doable so we could enjoy new features in the released distros.

[mjcarroll]

I responded on discord, but yes it's completely appropriate to revert before the sync goes out.

[adamdbrw]

I would vote for reforming the Worlds PR (#4) as addition only, and leave the refactoring part in the rolling distro for the next turtle. The Worlds PR only has a minor breaking change which can be easily removed into a separate PR.

[zakmat]

Hello @azeey, we have reverted the addition of 2.0.0 into already released distributions. Can you take a look at the PR #15 with the backport?