kube-proxy: Fix flag validation for healthz-bind-address and metrics-bind-address

[MrHohn]

What this PR does / why we need it: --healthz-bind-address and --metrics-bind-address are broken for kube-proxy as they do not allow ip:port format, though they claim to support it.

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): Fixes #53754

Special notes for your reviewer:
cc @ncdc

Release note:

Fix kube-proxy flags validation for --healthz-bind-address and --metrics-bind-address to allow specifying ip:port.

[ncdc]

@MrHohn do you plan to rebase this (to match the move from componentconfig to pkg/proxy/apis/kubeproxyconfig) for 1.9?

[MrHohn]

@ncdc Thanks for the reminder, I missed the rebase-needed signal. Will rebase and let you know.

[MrHohn]

@ncdc Rebased. Though IPPortVar is kept in componentconfig/helpers.go as I haven't figured out a better place.

[ncdc]

/lgtm

[ncdc]

/sig network

[MrHohn]

Thanks for the quick review.

/assign @mikedanese
for approval.

[MrHohn]

/retest

[MrHohn]

/test pull-kubernetes-unit

[BenTheElder]

/test pull-kubernetes-cross
[borrowing legitimate PR for test-infra purposes :-)]

[MrHohn]

/test pull-kubernetes-e2e-gce

[MrHohn]

/test pull-kubernetes-e2e-gce

[MrHohn]

/assign @bowei @thockin
It might be worth to get this in 1.9 (and cherrypick to 1.8, 1.7 as well). These two flags (especially --metrics-bind-address) are almost unusable without the fix.

[MrHohn]

/kind bug
/sig network
/priority critical-urgent

[MrHohn]

Updated PR for ipv6.

[MrHohn]

/retest

[bowei]

reads better if you just bail out early

if net.ParseIP(s) != nil {
  *v.Val = s
  return nil
}

...

[MrHohn]

Sounds good, done.

[bowei]

/lgtm

[bowei]

/approve

[krzyzacy]

/retest

[MrHohn]

@bowei @thockin PR is updated. Thanks!

[krzyzacy]

/test pull-kubernetes-bazel-build

[bowei]

/status approved-for-milestone

[mikedanese]

/approve

[mikedanese]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: bowei, mikedanese, MrHohn, ncdc

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

The pull request process is described here

Needs approval from an approver in each of these files:

• cmd/OWNERS [mikedanese]
• pkg/apis/componentconfig/OWNERS [mikedanese]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[k8s-github-robot]

/test all

Tests are more than 96 hours old. Re-running tests.

[k8s-github-robot]

/test all [submit-queue is verifying that this PR is safe to merge]

[k8s-github-robot]

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions here.