Upgrade base image from to Ubuntu 22.04 from 18.04

[yuvipanda]

18.04 was EOL May 2023, with only paid support now available (https://ubuntu.com/blog/18-04-end-of-standard-support).

Let's bump the default base image to 22.04. This might break some repos that have apt.txt based packages, but I don't really think there's a way around that. If specific package pinning is needed, users unfortunately need to use a Dockerfile.

Closes #1258

[minrk]

I agree that we need to do this, and after EOL seems like the absolute latest we can do it.

Until we have an opt-in path to selecting newer base images, we just have to make this breaking change.

[manics]

How about we make an announcement https://discourse.jupyter.org/tag/announcement before merging/deploying this to mybinder.org, to manage expectations?

[yuvipanda]

Can someone else take on making the announcement? :D

[consideRatio]

LGTM, it would be good to get a notice in the changelog as well under the unreleased section about this breaking change.

I've added a label about it breaking for now

[consideRatio]

How about we make an announcement https://discourse.jupyter.org/tag/announcement before merging/deploying this to mybinder.org, to manage expectations?

I wonder if we can and should announce this via mybinder.org directly instead of discourse if its to be announced, for example in a banner during loading? If something errors by failing to get installed, this is where they will be.

[rgaiacs]

I wonder if we can and should announce this via mybinder.org directly

It is a great idea.

[manics]

I wonder if we can and should announce this via mybinder.org directly instead of discourse if its to be announced

How about both? We're using Discourse as the support forum and questions about binder are often handled by non-jupyterhub community members, so I think it's polite to give everyone advance warning.

[minrk]

Both sound great. I can post to discourse.

[consideRatio]

I opened jupyterhub/mybinder.org-deploy#2663 about not using dev releases in mybinder.org, allowing us to link out to a repo2docker's changelog etc in announcements independently if they are on made on mybinder.org or discouse, where we anyhow would need to describe breaking changes.

Please signal agreement / disagreement or similar, if there is a clear agreement the fix is simple - we just adjust automation in mybinder.org-deploy to not bump to dev releases.

Practically, the action plan I suggest is:

1. We go for the suggestion in Stop using repo2docker's dev releases, use only stable (or non-dev pre-releases) mybinder.org-deploy#2663
2. We merge this PR, with a "unreleased" changelog entry made
3. We make a release of repo2docker
4. We observe in mybinder.org-deploy that "oh its a breaking change in the release we may bump to, maybe we should make a heads up announcement on discourse/mybinder.org before we merge this bump PR?"

[minrk]

Announcement on the forum

[minrk]

and banner for mybinder.org: jupyterhub/mybinder.org-deploy#2665

[yuvipanda]

Conversation in jupyterhub/mybinder.org-deploy#2663 has come to a conclusion to continue current practice. I think there's been enough lead time now! Anyone wanna hit the merge button? :)

[consideRatio]

I locally merged this on my computer and searched for 18.04, 20.04, bionic, focal, and found no outdated references besides one now fixed - this LGTM and seems ready for merge!

[manics]

I've posted one last warning https://discourse.jupyter.org/t/repo2docker-and-mybinder-org-upgrading-base-image-to-ubuntu-22-04/19865/2

[vishwa2710]

Hi all! Wondering if this is going to get merged anytime soon?

[consideRatio]

@yuvipanda @minrk @manics I went for a merge here. I verified that the tests still passed against the latest main branch.

[yuvipanda]

Yay, thanks @consideRatio :)