Update Flux controllers to Kustomize v5.0

[stefanprodan]

We should update Flux to Kustomize to v5.0.0 but this version comes with many breaking changes. One breaking change is the removal of the DoLegacyResourceSort which is used in Kubernetes cli-runtime. Given that the Flux controllers depend on k8s.io/cli-runtime, we are in stuck with Kustomize v4 until there is an official Kubernetes release that includes kustomize/api@v0.13.1 in cli-runtime.

Bumping sigs.k8s.io/kustomize/api to v0.13.1 in kustomize-controller results in:

# k8s.io/cli-runtime/pkg/resource
../../../../pkg/mod/k8s.io/cli-runtime@v0.26.1/pkg/resource/kustomizevisitor.go:41:8:
kOpts.DoLegacyResourceSort undefined (type *krusty.Options has no field or method DoLegacyResourceSort)

Use kustomize/api@v0.13.1 and kustomize/kyaml@v0.14.0 in:

• fluxcd/pkg
• fluxcd/kustomize-controller
• fluxcd/helm-controller
• fluxcd/image-automation-controller
• fluxcd/flux2

[stefanprodan]

This has been fixed upstream, Kustomize v5 will be shipped in Kubernetes 1.27 next week. After the release we can look into updating Flux.

[siegenthalerroger]

Is this aimed to be included in the v2 GA or will this be updated in a later release?

[stefanprodan]

Is this aimed to be included in the v2 GA or will this be updated in a later release?

We don't know yet. While Kubernetes cli-runtime was update, the Kubernetes cli-utils is still on the old Kustomize version https://github.com/kubernetes-sigs/cli-utils/blob/ed4ec48b3405206c6c2200adbbc9606ea46b4257/go.mod#L95

[stefanprodan]

We've started the upgrade, currently blocked by controller-runtime, ref: fluxcd/pkg#534

[stefanprodan]

We are now waiting on kubernetes-sigs/controller-runtime#2297 that depends on Kubernetes 1.27.2 (scheduled for 17th May).

[stefanprodan]

This is now done and will be part of Flux v2.0.0-rc.4 release