kubeadm: Migrate cert and PKI helpers to ClusterConfiguration

[rosti]

What this PR does / why we need it:

This PR is the second in a series, targeting the replacement of InitConfiguration with ClusterConfiguration, when the former is not needed. Please, review only the last commit.

This PR migrates cert and PKI helper APIs to use ClusterConfiguration (and away from InitConfiguration).

The certificate and PKI related helper APIs used InitConfiguration. With the introduction of ClusterConfiguration it became more viable to use that instead (in most cases in combination with NodeRegistrationOptions).

This change will allow us to avoid the use of InitConfiguration outside of kubeadm init

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
refs kubernetes/kubeadm#963

Special notes for your reviewer:

/cc @kubernetes/sig-cluster-lifecycle-pr-reviews
/area kubeadm
/kind enhancement
/assign @luxas
/assign @timothysc
/assign @fabriziopandini
/cc @stealthybox

Depends on:

• [reissue] kubeadm: Split out ClusterConfiguration from InitConfiguration #67441
• kubeadm: use ClusterConfiguration in images.go #67503

Release note:

NONE

[fabriziopandini]

/hold
@rosti please wait until the config file reworking is completed in order to avoid unnecessary reworks. E.g we are going to move advertise address out of ClusterConfiguration -> this might require to revert some changes in this pr

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: rosti
To fully approve this pull request, please assign additional approvers.
We suggest the following additional approver: fabriziopandini

If they are not already assigned, you can assign the PR to them by writing /assign @fabriziopandini in a comment when ready.

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/kubeadm/OWNERS

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

[rosti]

@fabriziopandini I can see your point here and I agree with the hold.
I did the PR thinking, that even if API server advertise address moves, it will likely be a move somewhere inside ClusterConfiguration as opposed to external. Thus, changing the interface to a combo of ClusterConfiguration and NodeRegistrationOptions looked safe to me.

[timothysc]

We are going to need to lock down the config for 1.12 and punt the rest of the shuffling to try and make a complete push to beta in 1.13.

[k8s-ci-robot]

@rosti: PR needs rebase.

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.

[neolit123]

do we still need this for 1.13?
i haven't checked.

[rosti]

Not in this form and certainly this should not have a high priority. I'll close this for now.

/close

[k8s-ci-robot]

@rosti: Closing this PR.

In response to this:

Not in this form and certainly this should not have a high priority. I'll close this for now.

/close

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.