Add pod-selector kubectl drain

[juanvallejo]

Release note:

Added the ability to select pods in a chosen node to be drained, based on given pod label-selector

This patch adds the ability to select pods in a chosen node to be drained, based on given pod label-selector. Related downstream issue: openshift/origin#17554

Further, it removes explicit, specific, pod-controller check. The drain command currently fails if a pod has a controller of a kind not explicitly handled in the command itself. This causes drain to be unusable if a node contains pods managed by third-party, or "unknown" controllers.

Based on this comment, the expectation was to fail if a pod's controller was not found for whatever reason. I believe that the drain command should not care about the existence of a pod controller. It should only care whether a pod has one, and act according to that controller kind. This solves a downstream bug: openshift/origin#17563

cc @fabianofranz @deads2k @kubernetes/sig-cli-misc

[k8s-ci-robot]

@juanvallejo: Reiterating the mentions to trigger a notification:
@kubernetes/sig-cli-misc

Details

In response to this:

Release note:

Added the ability to select pods in a chosen node to be drained, based on given pod label-selector

This patch adds the ability to select pods in a chosen node to be drained, based on given pod label-selector. Related downstream issue: openshift/origin#17554

Further, it removes explicit, specific, pod-controller check. The drain command currently fails if a pod has a controller of a kind not explicitly handled in the command itself. This causes drain to be unusable if a node contains pods managed by third-party, or "unknown" controllers.

Based on this comment, the expectation was to fail if a pod's controller was not found for whatever reason. I believe that the drain command should not care about the existence of a pod controller. It should only care whether a pod has one, and act according to that controller kind. This solves a downstream bug: openshift/origin#17563

Will add tests

cc @fabianofranz @deads2k @kubernetes/sig-cli-misc

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[cblecker]

/ok-to-test

[juanvallejo]

ping @fabianofranz or @soltysh

[juanvallejo]

@fabianofranz friendly ping

[deads2k]

This method no longer returns an error.

[deads2k]

Fix method signature, squash in your tests, then lgtm.

[deads2k]

Is this just?

if controllerRef != nil{
    return true, nil, nil
}
if o.Force{
    return true, &warning{kUnmanagedWarning}, nil
}

return false, nil, &fatal{kUnmanagedFatal}

[deads2k]

Use if's and early returns please

[deads2k]

comments and squash in that last commit.

[juanvallejo]

@deads2k thanks, done

[deads2k]

/lgtm

[deads2k]

/approve no-issue

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: deads2k, juanvallejo

Associated issue requirement bypassed by: deads2k

The full list of commands accepted by this bot can be found here.

Details

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• hack/OWNERS [deads2k]
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[k8s-github-robot]

Automatic merge from submit-queue (batch tested with PRs 55751, 57337, 56406, 56864, 57347). If you want to cherry-pick this change to another branch, please follow the instructions here.