[Blocked do not merge] ⚠️ (kustomize/v1,go/v3): upgrade kustomize 3.x to 4.x and add test to ensure backwards compatibility

[camilamacedo86]

Description

• Update kustomize from 3x to 4x
• Add script test to ensure that maintainers do not change the default scaffold of kustomize/v1 and go/v3 which are stable and we MUST ensure the backwards compatibility

IMPORTANT: The changes on the scaffolds to comply with the kustomize 4.x and remove what is deprecated must be done in the new kustomze/v2-alpha plugin (kubebuilder/pkg/plugins/common/kustomize/v2/) (examples as we did here)which will be used by a new golang plugin as go/v4-alpha. So that, we do not introduce breaking changes and do not affect those who scaffold the projects with Kubebuilder CLI 3.x and are trying to use its new versions. For further understanding of why it is required check the Plugin Versioning doc: https://book.kubebuilder.io/plugins/plugins-versioning.html

Motivation

Allow us to move forward and support Apple Silicon with go/v3 and kustomize/v1 without introducing breaking changes for those who scaffold the projects with old CLI versions.

BLOCKED BY

/hold

By testing the changes with its big consumer SDK we could find that the make bundle target on their project brokes:

```sh
$ make bundle
/Users/camilamacedo86/go/src/github.com/operator-framework/operator-sdk/testdata/go/v3/memcached-operator/bin/controller-gen rbac:roleName=manager-role crd webhook paths="./..." output:crd:artifacts:config=config/crd/bases
operator-sdk generate kustomize manifests --interactive=false -q
cd config/manager && /Users/camilamacedo86/go/src/github.com/operator-framework/operator-sdk/testdata/go/v3/memcached-operator/bin/kustomize edit set image controller=controller:latest
/Users/camilamacedo86/go/src/github.com/operator-framework/operator-sdk/testdata/go/v3/memcached-operator/bin/kustomize build config/manifests | operator-sdk generate bundle -q --overwrite --version 0.0.1  
Error: remove operation does not apply: doc is missing path: "/spec/template/spec/containers/1/volumeMounts/0": missing value

So, we cannot move forward with this one for safety and for not to risk introducing breaking changes for the projects which consume Kubebuilder as lib. See that the kustomize documentation about what should no longer work when we move from v3 to v4 is not very clear.

[camilamacedo86]

About errors in the CI/prow:

Regards APIDiff / Verify API differences (pull_request)

That is OK. We have the check to not allow we break the API.
In this case the check fails because see that we bump the kustomze only
We can safely move forward here.

[camilamacedo86]

/test pull-kubebuilder-e2e-k8s-1-18-20

[everettraven]

Looks good, just a minor spelling nit.

[FillZpp]

The macos-latest unit-test failed because of Github rate-limiter failed the request. Either authenticate or wait a couple of minutes., should we re-run it or just ignore?

[camilamacedo86]

Hi @FillZpp,

The macos-latest unit-test failed because of Github rate-limiter failed the request. Either authenticate or wait a couple of minutes., should we re-run it or just ignore?

We should not ignore this test.
It was a flake and I re-run the test which is passing now.
Thank you

[FillZpp]

/lgtm

[everettraven]

Looks good!

[rashmigottipati]

/lgtm
/hold to allow addressing of nits from reviews

[rashmigottipati]

Also, it looks like the Kustomize version in scaffolds is not updated to v4.5.5 from v3.5.4 which is causing the APIDiff test to fail.

[camilamacedo86]

Hi @rashmigottipati,

Also, it looks like the Kustomize version in scaffolds is not updated to v4.5.5 from v3.5.4 which is causing the APIDiff test to fail.

The APIDiff comply with is expected in this case. In this scenarios, the bot does not merge alone we need to force

[rashmigottipati]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: camilamacedo86, everettraven, rashmigottipati

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

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• OWNERS [camilamacedo86]

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[rashmigottipati]

/test pull-kubebuilder-e2e-k8s-1-18-20

[camilamacedo86]

/test pull-kubebuilder-e2e-k8s-1-18-20

[k8s-ci-robot]

New changes are detected. LGTM label has been removed.

[camilamacedo86]

/hold

[camilamacedo86]

I am closing this one and we can reopen if we check that we can move forward here.