fix: chart crd forceUpgrade field should be nil by default

[emosbaugh]

Description

Even though the forceUpgrade field is a nil pointer, the k8s controller seems to be setting the field automatically in CRs that exist once the CRD is updated via a k0s upgrade. I believe this is because it defaults to true via the generated openapi spec.

              forceUpgrade:
                default: true
                description: 'ForceUpgrade when set to false, disables the use of
                  the "--force" flag when upgrading the the chart (default: true).'
                type: boolean

This results in a backwards incompatible change for those importing the schema prior to this version.

W1001 20:21:35.308507       1 reflector.go:539] pkg/mod/k8s.io/client-go@v0.29.2/tools/cache/reflector.go:229: failed to list *v1beta1.ClusterConfig: json: unknown field "forceUpgrade"

$ curl -sSLf https://get.k0s.sh | sudo K0S_VERSION=v1.29.8+k0s.0 sh
$ sudo k0s install controller --single --config k0s.yaml --enable-dynamic-config
$ sudo k0s start
$ sudo k0s kubectl get clusterconfigs -A -oyaml
apiVersion: v1
items:
- apiVersion: k0s.k0sproject.io/v1beta1
  kind: ClusterConfig
  metadata:
    creationTimestamp: "2024-10-02T15:59:08Z"
    generation: 1
    name: k0s
    namespace: kube-system
    resourceVersion: "199"
    uid: 6b31fcff-9901-4545-bd4d-5c406052a7a4
  spec:
    extensions:
      helm:
        charts:
        - chartname: twuni/docker-registry
          name: docker-registry
          namespace: registry
          order: 0
          timeout: 0
          values: ""
          version: 2.2.3
        concurrencyLevel: 5

$ sudo k0s stop
$ curl -sSLf https://get.k0s.sh | sudo K0S_VERSION=v1.29.9+k0s.0 sh
$ sudo k0s start
$ sudo k0s kubectl get clusterconfigs -A -oyaml
apiVersion: v1
items:
- apiVersion: k0s.k0sproject.io/v1beta1
  kind: ClusterConfig
  metadata:
    creationTimestamp: "2024-10-02T15:59:08Z"
    generation: 1
    name: k0s
    namespace: kube-system
    resourceVersion: "199"
    uid: 6b31fcff-9901-4545-bd4d-5c406052a7a4
  spec:
    extensions:
      helm:
        charts:
        - chartname: twuni/docker-registry
          forceUpgrade: true
          name: docker-registry
          namespace: registry
          order: 0
          timeout: 0
          values: ""
          version: 2.2.3
        concurrencyLevel: 5

Fixes # (issue)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

How Has This Been Tested?

• Manual test
• Auto test added

$ curl -sSLf https://get.k0s.sh | sudo K0S_VERSION=v1.29.8+k0s.0 sh
$ sudo k0s install controller --single --config k0s.yaml --enable-dynamic-config
$ sudo k0s start
$ sudo k0s kubectl get clusterconfigs -A -oyaml
apiVersion: v1
items:
- apiVersion: k0s.k0sproject.io/v1beta1
  kind: ClusterConfig
  metadata:
    creationTimestamp: "2024-10-02T15:59:08Z"
    generation: 1
    name: k0s
    namespace: kube-system
    resourceVersion: "199"
    uid: 6b31fcff-9901-4545-bd4d-5c406052a7a4
  spec:
    extensions:
      helm:
        charts:
        - chartname: twuni/docker-registry
          name: docker-registry
          namespace: registry
          order: 0
          timeout: 0
          values: ""
          version: 2.2.3
        concurrencyLevel: 5

$ sudo k0s stop
$ # Install custom build
$ sudo k0s start
$ sudo k0s kubectl get crd clusterconfigs.k0s.k0sproject.io -oyaml | grep forceUpgrade: -A 6
                            forceUpgrade:
                              description: 'ForceUpgrade when set to false, disables
                                the use of the "--force" flag when upgrading the the
                                chart (default: true).'
                              type: boolean
                            name:
                              type: string
$ sudo k0s kubectl get clusterconfigs -A -oyaml
apiVersion: v1
items:
- apiVersion: k0s.k0sproject.io/v1beta1
  kind: ClusterConfig
  metadata:
    creationTimestamp: "2024-10-02T16:05:16Z"
    generation: 1
    name: k0s
    namespace: kube-system
    resourceVersion: "199"
    uid: 4f079d8f-f8e2-4e92-b980-4d137b409c31
  spec:
    extensions:
      helm:
        charts:
        - chartname: twuni/docker-registry
          name: docker-registry
          namespace: registry
          order: 0
          timeout: 0
          values: ""
          version: 2.2.3
        concurrencyLevel: 5

To test for forward compatibility, install the latest k0s 1.30 release and see that it upgrades fine back to default: true.

$ sudo k0s stop
$ curl -sSLf https://get.k0s.sh | sudo K0S_VERSION=v1.30.5+k0s.0 sh
$ sudo k0s start
$ sudo k0s kubectl version
Client Version: v1.30.5
Kustomize Version: v5.0.4-0.20230601165947-6ce0bf390ce3
Server Version: v1.30.5+k0s
$ sudo k0s kubectl get clusterconfigs -A -oyaml
apiVersion: v1
items:
- apiVersion: k0s.k0sproject.io/v1beta1
  kind: ClusterConfig
  metadata:
    creationTimestamp: "2024-10-02T16:05:16Z"
    generation: 1
    name: k0s
    namespace: kube-system
    resourceVersion: "199"
    uid: 4f079d8f-f8e2-4e92-b980-4d137b409c31
  spec:
    extensions:
      helm:
        charts:
        - chartname: twuni/docker-registry
          forceUpgrade: true
          name: docker-registry
          namespace: registry
          order: 0
          timeout: 0
          values: ""
          version: 2.2.3
        concurrencyLevel: 5

Checklist:

• My code follows the style guidelines of this project
• My commit messages are signed-off
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

[twz123]

/xref #4866

[k0s-bot]

Successfully created backport PR for release-1.31:

• [Backport release-1.31] fix: chart crd forceUpgrade field should be nil by default #5070