🌱 ClusterClass: add condition for references with outdated apiVersions

[sbueringer]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #7212

[sbueringer]

I chose to add a separate condition for validation.

Failure state:

status:
  conditions:
  - lastTransitionTime: "2022-09-21T13:56:46Z"
    message: infrastructure.cluster.x-k8s.io/v1alpha4, Kind=DockerClusterTemplate
      should be infrastructure.cluster.x-k8s.io/v1beta1, Kind=DockerClusterTemplate,
      infrastructure.cluster.x-k8s.io/v1alpha4, Kind=DockerMachineTemplate should
      be infrastructure.cluster.x-k8s.io/v1beta1, Kind=DockerMachineTemplate, infrastructure.cluster.x-k8s.io/v1alpha4,
      Kind=DockerMachineTemplate should be infrastructure.cluster.x-k8s.io/v1beta1,
      Kind=DockerMachineTemplate
    reason: OutdatedAPIVersionsInReferences
    severity: Warning
    status: "False"
    type: ClusterClassValidationSucceeded

Success state:

status:
  conditions:
  - lastTransitionTime: "2022-09-21T13:56:46Z"
    status: "true"
    type: ClusterClassValidationSucceeded

There are a few alternatives:

• Using a Ready condition instead => not sure what ready would mean for a ClusterClass, just because old refs are used the ClusterClass is not really "un-ready"
• Using a more specific condition like APIVersionsUpToDate

Opinions? @fabriziopandini @vincepri @fabriziopandini @killianmuldoon

P.S. Some prior art: CRDs have some validation conditions: https://github.com/kubernetes/kubernetes/blob/e3f2d237fdb225e4835cd0985104bf01cabf6cd3/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1/types.go#L282-L301 (but they are afaik not all compliant with our conventions, e.g. Condition types MUST have a consistent polarity (i.e. "True = good"))

[fabriziopandini]

First pass

WRt to question above:

• I'm +1 to use Using a more specific condition like APIVersionsUpToDate, or simply ReferenceUpToDate (I prefer the second one)
• I'm -1 to use Ready condition because it is reserved for being used as a summary of all conditions; however, I will not add ready at the current stage (it is optional in the policy)

[sbueringer]

First pass

WRt to question above:

• I'm +1 to use Using a more specific condition like APIVersionsUpToDate, or simply ReferenceUpToDate (I prefer the second one)
• I'm -1 to use Ready condition because it is reserved for being used as a summary of all conditions; however, I will not add ready at the current stage (it is optional in the policy)

Thx good point, adjusted accordingly

[sbueringer]

Should be ready for another round of review now

[sbueringer]

@fabriziopandini When you have some time, would be good to get your input on condition / reason names

[sbueringer]

@fabriziopandini @vincepri constants adjusted, PTAL

[sbueringer]

/test pull-cluster-api-e2e-full-main

[fabriziopandini]

/lgtm

[sbueringer]

/assign @vincepri
for final approval

[ykakarap]

How about using a different seperator like ; (or something else). GVK when converted to string already has , in it. The output string could be confusing.

Also, the message only uses the GVK of the ref which does not include the name. If a few DockerMachineTemplate refs are outdated that tt could be confusing if the mesage just repeats that a DockerMachineTemplate ref is outdated without pointing to the correct ref.

[sbueringer]

I changed it to use a quoted string. Kept using , as separater seems slight more grammatically correct. The condition now looks like this:

  status:
    conditions:
    - lastTransitionTime: "2022-10-07T10:04:22Z"
      message: Ref "infrastructure.cluster.x-k8s.io/v1alpha4, Kind=DockerClusterTemplate
        default/quick-start-my-cluster" should be "infrastructure.cluster.x-k8s.io/v1beta1,
        Kind=DockerClusterTemplate default/quick-start-my-cluster", Ref "infrastructure.cluster.x-k8s.io/v1alpha4,
        Kind=DockerMachineTemplate default/quick-start-control-plane" should be "infrastructure.cluster.x-k8s.io/v1beta1,
        Kind=DockerMachineTemplate default/quick-start-control-plane", Ref "infrastructure.cluster.x-k8s.io/v1alpha4,
        Kind=DockerMachineTemplate default/quick-start-docker-worker-machinetemplate"
        should be "infrastructure.cluster.x-k8s.io/v1beta1, Kind=DockerMachineTemplate
        default/quick-start-docker-worker-machinetemplate"
      reason: OutdatedRefVersions
      severity: Warning
      status: "False"
      type: RefVersionsUpToDate

It's a bit verbose, but also very explicit which is probably a good thing

[fabriziopandini]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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:

• OWNERS [fabriziopandini]

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