Migrate ResourceClaimTemplate from resource.k8s.io/v1beta1

ResourceClaimTemplate creates a ResourceClaim for each pod that references it, the way a volume claim template does for storage. Kubernetes 1.38 is scheduled to stop serving v1beta1. Move to resource.k8s.io/v1, available since 1.34.

The error

Once the cluster runs 1.38, kubectl apply fails like this:

error: resource mapping not found for name: "<name>" namespace: "<ns>" from "<file>": no matches for kind "ResourceClaimTemplate" in version "resource.k8s.io/v1beta1"
ensure CRDs are installed first

What replaces it

Replacement: resource.k8s.io/v1
Available since: 1.34
Deprecated in: 1.35
Removed in: 1.38 (scheduled)

Check your manifests in the checker, or read the official documentation.

Migration notes

Beta APIs expire three releases after deprecation; the API server stops serving this one from 1.38.
The v1.33 release notes announced removal in 1.36; the v1.37.2 source tags say 1.38.

Helm upgrade fails after a cluster upgrade

If you installed this with Helm, helm upgrade can fail after the cluster is upgraded, even if the chart is already fixed. Which error appears depends on your Helm version and the error text:

Error: UPGRADE FAILED: unable to build kubernetes objects from current release manifest: resource mapping not found for name: "<name>" namespace: "<ns>" from "": no matches for kind "ResourceClaimTemplate" in version "resource.k8s.io/v1beta1"

Error: UPGRADE FAILED: current release manifest contains removed kubernetes api(s) for this kubernetes version and it is therefore unable to build the kubernetes objects for performing the diff. error from kubernetes: unable to recognize "": no matches for kind "ResourceClaimTemplate" in version "resource.k8s.io/v1beta1"

Helm compares your chart with the manifest stored with the release. That stored manifest still has the old API, and the cluster can no longer read it.

To check, get the stored manifest, and paste the output into the checker:

helm get manifest <release> -n <namespace>

To fix the stored record, use the helm-mapkubeapis plugin, latest tag v0.6.1. Try --dry-run first. Its README lists support for Helm v3, so check that it suits your Helm version.

helm plugin install https://github.com/helm/helm-mapkubeapis --version v0.6.1
helm mapkubeapis <release> --namespace <namespace> --dry-run

Helm's advice is to move releases to supported APIs before you upgrade the cluster, and not to roll back to a release from before that change.