feat(ubuntu): Add Ubuntu 25.04

[polarctos]

What this PR does / why we need it:

This adds the latest Ubuntu release 25.04 (Plucky Puffin) which will be supported from April 2025 until January 2026.

Version 25.04 is not a LTS release so it could be debated if it necessary to include it.
However one of the nice benefits of kubevirt compared to containers in Kubernetes is the possibility to run newer Linux kernels, thus having access to current releases as a trusted published containerdisk is very useful.

At a current point in the time there would be up to 5 Ubuntu versions in standard support, 3 LTS releases and up to 2 current releases: https://ubuntu.com/about/release-cycle or https://endoflife.date/ubuntu
So the noise of a still very well manageable number of current Ubuntu versions is still acceptable from my perspective.

As another example the Docker official images for Ubuntu also have the non-LTS releases during their standard support window, thus 5 versions there too: https://hub.docker.com/_/ubuntu/

When the support window for this non-LTS version ends, it can just be replaced by the next successor version. As the old tags remain in the quay.io registry there is no risk of breaking configs as the old versions can still be referenced, they just don't receive updates anymore then.

Release note:

Added support for Ubuntu 25.04 (Plucky Puffin)

[sourcery-ai]

Reviewer's Guide by Sourcery

This pull request adds support for Ubuntu 25.04 (Plucky Puffin) to the static registry, including artifacts for x86_64, aarch64, and s390x architectures. This allows users to run the latest Ubuntu release within kubevirt.

Updated class diagram for the static registry

classDiagram
  class Entry {
    Artifacts: []Artifact
    UseForDocs: bool
  }
  class Artifact {
    // Assuming Artifact is an interface or abstract class
  }
  class Ubuntu {
    +New(version string, arch string, env map[string]string) Artifact
  }

  Entry --|> Artifact : contains
  Ubuntu --|> Artifact : implements

  note for Entry "Entry now includes Ubuntu 25.04"

Loading

File-Level Changes

Change	Details	Files
Added support for Ubuntu 25.04 (Plucky Puffin) for x86_64, aarch64, and s390x architectures.	Added a new entry to the static registry for Ubuntu 25.04. Created artifacts for x86_64, aarch64, and s390x architectures with default environment variables.	cmd/medius/common/registry.go

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[kubevirt-bot]

Hi @polarctos. Thanks for your PR.

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[sourcery-ai]

Hey @polarctos - I've reviewed your changes - here's some feedback:

Overall Comments:

• Consider adding a comment explaining why UseForDocs is set to false for the new Ubuntu version.

Here's what I looked at during the review

• 🟢 General issues: all looks good
• 🟢 Security: all looks good
• 🟢 Testing: all looks good
• 🟢 Complexity: all looks good
• 🟢 Documentation: all looks good

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[lyarwood]

This adds the latest Ubuntu release 25.04 (Plucky Puffin) which will be supported from April 2025 until January 2026.

Looking at 24.10 the only way I think we could do this if we introduce some kind of limited retention policy for these images to reduce the number we are carrying at one time. I know we looked into this through quay itself in the past but we could also just implement the same directly in the project.

@codingben @jcanocan @0xFelix thoughts?

[jcanocan]

This adds the latest Ubuntu release 25.04 (Plucky Puffin) which will be supported from April 2025 until January 2026.

Looking at 24.10 the only way I think we could do this if we introduce some kind of limited retention policy for these images to reduce the number we are carrying at one time. I know we looked into this through quay itself in the past but we could also just implement the same directly in the project.

@codingben @jcanocan @0xFelix thoughts?

What would be the idea? Maybe to introduce a new field for non-LTS with a due to date or something similar?

[lyarwood]

This adds the latest Ubuntu release 25.04 (Plucky Puffin) which will be supported from April 2025 until January 2026.

Looking at 24.10 the only way I think we could do this if we introduce some kind of limited retention policy for these images to reduce the number we are carrying at one time. I know we looked into this through quay itself in the past but we could also just implement the same directly in the project.
@codingben @jcanocan @0xFelix thoughts?

What would be the idea? Maybe to introduce a new field for non-LTS with a due to date or something similar?

That or the number of old versions to keep or just a plain bool to only keep the latest.

[0xFelix]

There were plans to add a purge mechanism to the containerdisk tool in the past already. It's not in the scope of this PR but eventually we need a mechanism like that.

[codingben]

This adds the latest Ubuntu release 25.04 (Plucky Puffin) which will be supported from April 2025 until January 2026.

Looking at 24.10 the only way I think we could do this if we introduce some kind of limited retention policy for these images to reduce the number we are carrying at one time. I know we looked into this through quay itself in the past but we could also just implement the same directly in the project.

@codingben @jcanocan @0xFelix thoughts?

Can't we enable "prune image tags by creation date"? There is an open issue to discuss it: #101.

[jcanocan]

This adds the latest Ubuntu release 25.04 (Plucky Puffin) which will be supported from April 2025 until January 2026.

Looking at 24.10 the only way I think we could do this if we introduce some kind of limited retention policy for these images to reduce the number we are carrying at one time. I know we looked into this through quay itself in the past but we could also just implement the same directly in the project.
@codingben @jcanocan @0xFelix thoughts?

Can't we enable "prune image tags by creation date"? There is an open issue to discuss it: #101.

I wasn't aware of such a mechanism. But maybe it will be a good mid-term solution.

[0xFelix]

@codingben The feature as a whole needs to be groomed a little further. Expiring images only by creation date might lead to removal of all disks in a repository which we don't want.

[polarctos]

Looking at the previous short term support version of Ubuntu 24.10, over the total lifetime there were just 13 actual released image versions. So this is maybe actually not that many. For the Ubuntu 25.04 added in this PR there are currently 2 released image versions.

Would it be possible to have this Ubuntu version added and then a general purge mechanism be designed separately?

[0xFelix]

Sounds fine to me!

/approve

[kubevirt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: 0xFelix

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[jcanocan]

/lgtm