Use CronJob batch/v1 resource version if available

The batch/v2alpha1 CronJob type definitions and clients are
deprecated and removed in Kubernetes v1.21

Signed-off-by: Konstantin Misyutin <[email protected]>

Author: ikeeip

deploy/helm/kubernetes/templates/_helpers.tpl

@@ -23,6 +23,13 @@ We truncate at 63 chars because some Kubernetes name fields are limited to this
 {{- end -}}
 {{- end -}}
 
+{{/*
+Generate compatible "CronJob" resource API version.
+*/}}
+{{- define "apiVersion.CronJob" -}}
+{{- if .Capabilities.APIVersions.Has "batch/v1/CronJob" -}}batch/v1{{- else -}}batch/v1beta1{{- end -}}
+{{- end -}}
+
 {{/*
 Create a default certificate name.
 */}}

deploy/helm/kubernetes/templates/etcd-backup-cronjob.yaml

@@ -1,7 +1,7 @@
 {{- if .Values.etcd.backup.enabled }}
 {{- $fullName := include "kubernetes.fullname" . -}}
 ---
-apiVersion: batch/v1beta1
+apiVersion: {{ include "apiVersion.CronJob" . }}
 kind: CronJob
 metadata:
   name: {{ $fullName }}-etcd-backup

deploy/helm/kubernetes/templates/kubeadm-cronjob.yaml

@@ -1,7 +1,7 @@
 {{- if .Values.admin.job.enabled }}
 {{- $fullName := include "kubernetes.fullname" . -}}
 ---
-apiVersion: batch/v1beta1
+apiVersion: {{ include "apiVersion.CronJob" . }}
 kind: CronJob
 metadata:
   name: "{{ $fullName }}-kubeadm-tasks"