Add subresource support to kubectl

[nikhita]

Enhancement Description

• One-line enhancement description (can be used as a release note): Add a new flag --subresource to kubectl commands like get, patch, edit and replace commands to allow fetching and updating subresources like status, scale, etc.
• Kubernetes Enhancement Proposal: https://github.com/kubernetes/enhancements/tree/master/keps/sig-cli/2590-kubectl-subresource
• Discussion Link:
  • Discussion in the POC PR - kubectl: support --subresource flag kubernetes#99556
  • mailing list/meeting link: https://youtu.be/zUa7dudYCQM?t=299
• Primary contact (assignee): @nikhita @MadhavJivrajani
• Responsible SIGs: SIG CLI
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y): v1.24
  • Beta release target (x.y): v1.27
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s):
    • kubectl subresource KEP #2600
  • Code (k/k) update PR(s):
    • apiserver changes - kubectl: apiserver changes to add --subresource support kubernetes#103516
    • kubectl changes - kubectl: support --subresource flag kubernetes#99556
  • Docs (k/website) update PR(s):
    • Document kubectl subresource support website#32604
• Beta
  • KEP (k/enhancements) update PR(s):
    • KEP-2590: graduate kubectl subresource support to beta #3729
  • Code (k/k) update PR(s):
    • kubectl: Change subresource flag to beta kubernetes#116595
    • test/e2e: Add e2e tests for kubectl --subresource kubernetes#116590
    • test/e2e: Fix flaking subresource test kubernetes#116619
  • Docs (k/website) update(s):
    • reference/kubectl: Update docs for moving kubectl subresource to beta website#39828

/sig cli
/assign @nikhita @ykakarap
cc @eddiezane @soltysh @seans3 @pwittrock

[JamesLaverack]

/stage alpha
/milestone v1.22

[salaxander]

Hi @nikhita , 1.22 enhancements team here!

For the enhancement to be included in the milestone, it must meet the following criteria:

• The KEP must be merged in an implementable state
• [DONE] The KEP must have test plans
• [DONE] The KEP must have graduation criteria
• The KEP must have a production readiness review

In order to move forward in 1.22 we'd need to get the KEP merged as well as a production readiness review before enhancements freeze on 5/13. Let us know if there's anything we can do to help before then.

Thanks!!

[ykakarap]

Hi @salaxander, @nikhita and I are working in this together.
Thanks for the heads-up on the pending items for the KEP :).

Regarding the production readiness review, the KEP doc has a section by the same name. Does this section satisfy the required criteria? If not, can you let us know what is missing from it.
Thanks!

[salaxander]

Hi @ykakarap! - Here's the full documentation on the production readiness review process -> https://github.com/kubernetes/community/blob/master/sig-architecture/production-readiness.md

[soltysh]

#2600 merged so we should be all good now.

[chrisnegus]

Hi @nikhita 👋 1.22 Docs Shadow here.
This enhancement is marked as Needs Docs for the 1.22 release.

Please follow the steps detailed in the documentation to open a PR against dev-1.22 in the kubernetes/website repo. This PR can be just a placeholder at this time and must be created before Fri July 9, 11:59 PM PDT.

Also, take a look at Documenting for a release to familiarize yourself with the docs requirement for the release.

Thank you!

[ykakarap]

@chrisnegus Thanks for the heads-up! :)

Will follow the steps to do it.

[salaxander]

Hi @nikhita and @ykakarap - Just checking in as we're about 2 weeks away from 1.22 code freeze. Are there any open or merged k/k PRs we should be tracking for this? Thanks!!

[ykakarap]

Hey @salaxander the final PR will be read in a day or 2.

[ykakarap]

Hey @salaxander, this is the corresponding PR: kubernetes/kubernetes#99556.

[salaxander]

Hi @ykakarap - One more check-in as we're a week away from code freeze. Any updates on if you expect kubernetes/kubernetes#99556 to merge before the deadline?

Thanks!

[ykakarap]

Hi @salaxander, I expect the PR to be merged before the deadline. SIG CLI has already reviewed the code.

cc @nikhita

[salaxander]

Hey @ykakarap - I see the PR is approved, but there are merge conflicts at the moment. It'll need to merge before code freeze tomorrow evening to be included in 1.22. Let us know if there's anything we can do to help :)

[ykakarap]

@salaxander thanks for offering to help :)

There is still some work that needs to be done before the PR can be merged.
I will drop a message here tomorrow to update the status of the PR.

[ritpanjw]

Hi @nikhita 👋 1.22 Docs Shadow here.
This enhancement is marked as Needs Docs for the 1.22 release.

Please follow the steps detailed in the documentation to open a PR against dev-1.22 in the kubernetes/website repo. This PR can be just a placeholder at this time and must be created before Fri July 9, 11:59 PM PDT.

Also, take a look at Documenting for a release to familiarize yourself with the docs requirement for the release.

Thank you!

@nikhita @salaxander Friendly reminder about the upcoming docs placeholder PR deadline tomorrow
on Fri July 9, 11:59 PM PDT.

[ykakarap]

@salaxander @ritpanjw We are planning to move this enhancement to the next release. Please let me know if there is anything I need to do to note that.

[salaxander]

Hi @ykakarap - I'll update it in our tracking, thanks for letting me know!

[soltysh]

/milestone v1.23

[SerialVelocity]

/remove-lifecycle rotten

Hope I'm doing the right thing by removing the tag because This feature has merged as an alpha feature, has good feedback, so should be moved to be a beta feature soon? (just summarising the above)

[soltysh]

@nikhita @MadhavJivrajani are you planning to push this through beta in 1.27?

[nikhita]

@soltysh yes!

[nikhita]

@soltysh created #3729

[soltysh]

/stage beta
/label lead-opted-in
/milestone v1.27

[thockin]

Is this aiming to support any subresources other than status, eventually?

[marosset]

Hello @nikhita & @MadhavJivrajani 👋, Enhancements team here.

Just checking in as we approach enhancements freeze on 18:00 PDT Thursday 9th February 2023.

This enhancement is targeting for stage beta for v1.27 (correct me, if otherwise)

Here's where this enhancement currently stands:

• KEP readme using the latest template has been merged into the k/enhancements repo.
• KEP status is marked as implementable for latest-milestone: v1.27
• KEP readme has a updated detailed test plan section filled out
• KEP readme has up to date graduation criteria
• KEP has a production readiness review that has been completed and merged into k/enhancements.

For this enhancement, it looks like #3729 will address all of the remaining requirements.

The status of this enhancement is marked as at risk. Please keep the issue description up-to-date with appropriate stages as well. Thank you!

[nikhita]

Is this aiming to support any subresources other than status, eventually?

@thockin scale is also supported right now. Which other subresources would you like to see support for?

[thockin]

Oh, I didn't know scale was supported! That was what I was thinking.

[thockin]

Wait:

$ make kubectl
go version go1.19.5 linux/amd64
+++ [0203 17:47:48] Building go targets for linux/amd64
    k8s.io/kubernetes/cmd/kubectl (static)

$ ./_output/bin/kubectl edit deploy iamyouare --subresource=scale
error: invalid subresource value: "scale". Must be one of [status]

Am I doing it wrong?

[marosset]

With #3729 merged this enhancement is ready to be tracked for v1.27
Thanks!

[nikhita]

@thockin ah, good catch!

It looks like edit was deliberately written to not support scale:

https://github.com/kubernetes/kubernetes/blob/b7ad17978eaba508c560f81bab2fb9d0b256e469/staging/src/k8s.io/kubectl/pkg/cmd/util/editor/editoptions.go#L57

To be honest, I can't remember why we decided to do this but I'll follow up on this to either: 1) add support or 2) document this behavior.

scale is supported for get, patch and replace commands though!

[LukeMwila]

Hi @MadhavJivrajani @nikhita, I’m reaching out from the 1.27 Release Docs team. This enhancement is marked as ‘Needs Docs’ for the 1.27 release.

Please follow the steps detailed in the documentation to open a PR against dev-1.27 branch in the k/website repo. This PR can be just a placeholder at this time, and must be created by March 16. For more information, please take a look at Documenting for a release to familiarize yourself with the documentation requirements for the release.

Please feel free to reach out with any questions. Thanks!

[shatoboar]

Hi @nikhita 👋,
Checking in as we approach 1.27 code freeze at 17:00 PDT on Tuesday 14th March 2023.
Please ensure the following items are completed:

• All PRs to the Kubernetes repo that are related to your enhancement are linked in the above issue description (for tracking purposes).
• All PRs are fully merged by the code freeze deadline.

Please let me know what PRs in k/k I should be tracking for this KEP.
As always, we are here to help should questions come up. Thanks!

[MadhavJivrajani]

Hi @shatoboar
Most of the The PRs for this KEP are linked in the issue, here's an exhaustive list:
KEP (k/enhancements) update PR(s):

• KEP-2590: graduate kubectl subresource support to beta #3729
  Code (k/k) update PR(s):
• kubectl: Change subresource flag to beta kubernetes#116595
• test/e2e: Add e2e tests for kubectl --subresource kubernetes#116590
• test/e2e: Fix flaking subresource test kubernetes#116619
• test/e2e: Improve kubectl subresource e2e test kubernetes#116639
  Docs (k/website) update(s):
• reference/kubectl: Update docs for moving kubectl subresource to beta website#39828