Hi -devel,
Historically, the container stack, which is composed by src:docker.io, src:containerd and src:runc, has diverged from Debian to deliver the "upstream" experience to our users [1] instead of worrying too much about backward compatibility or regressions. However, recently, those fast-moving projects have been introducing some breaking changes which have impacted an increasing number of packages (Golang specifically) in the archive. Not just the breaking changes have been an issue but also the way we maintain those packages, bundling all the vendor code (rdeps cannot load the vendor code without introducing a delta), so we can easily backport them to old releases.
With that in mind, we, the Server team, identified the need to decouple the application (what users really use) and the library (what is used by rdeps) in a way that, on the one hand, we can keep following upstream projects without worrying about breaking changes and on the other hand, we keep the library (-dev package) stable to avoid breakages of packages sync'ed from Debian or already in stable releases during SRUs.
The way this decoupling was implemented this cycle (Mantic) can be summarized as follows:
- src:docker.io now provides just the -dev package (library) and it is in "sync" with Debian, without bundled vendor code (i.e., with proper dependencies on Debian packages). Sync is in quotation marks because there is a delta to make it not provide the docker.io binary anymore (application). And now there is a new src:docker.io-app, which provides just the application and the documentation for our users.
- The same was done to src:containerd. Now, src:containerd provides just the library and src:containerd-app provides the application.
- src:runc was kept as is, one source package providing application and library. It will very likely follow docker.io and containerd in the next cycle. It was not done now because it has not presented big issues, but for consistency we will follow the same pattern. I'll let you know once this happens.
The changes listed above are about to be SRU'ed to all supported releases [2].
With that, the -dev packages of docker.io and containerd will be kept stable in all supported releases from now on (also devel). And in the near future, the same will happen for runc. Just the -app source packages will be updated across all releases with major version bumps; I'll be working on updating the current SRU exception to cover those changes.
I've sent a heads-up email to people actively working on those packages (Security and CPC) but here is another reminder.
[1] https://wiki.ubuntu.com/DockerUpdates
[2] https://bugs.launchpad.net/ubuntu/lunar/+source/docker.io-app/+bug/2022390
Cheers!
-- Lucas Kanashiro
