magnum-capi-helm-charts/charts/openstack-cluster/templates/node-group/kubeadm-config-template.yaml

{{/*
  In order for changes to the kubeadm config to be applied to existing machines,
  kubeadm config templates must be treated as immutable. This means that we must
  create a new one when the spec changes and update the ref in the corresponding
  machine deployment, which will trigger a rollout of new machines with the new
  kubeadm config.

  If the kubeadm config is updated in place, it will apply to new machine (e.g. on
  a scale out operation), but will not be applied to existing machines.

  To do this, we create a new template whenever the checksum of the spec changes.
*/}}

{{- define "openstack-cluster.nodegroup.kct.spec" -}}
{{- $ctx := index . 0 }}
{{- $nodeGroup := index . 1 }}
{{- include "openstack-cluster.kubeadmConfigSpec" (list $ctx $nodeGroup.kubeadmConfigSpec) }}
{{- end }}

{{- define "openstack-cluster.nodegroup.kct.checksum" -}}
{{- include "openstack-cluster.nodegroup.kct.spec" . | sha256sum }}
{{- end }}

{{- define "openstack-cluster.nodegroup.kct.name" -}}
{{- $ctx := index . 0 }}
{{- $nodeGroup := index . 1 }}
{{- $checksum := include "openstack-cluster.nodegroup.kct.checksum" . }}
{{- include "openstack-cluster.componentName" (list $ctx $nodeGroup.name) }}-{{ trunc 8 $checksum }}
{{- end }}

{{- range $nodeGroupOverrides := .Values.nodeGroups }}
{{- $nodeGroup := deepCopy $.Values.nodeGroupDefaults | mustMerge $nodeGroupOverrides }}
---
apiVersion: bootstrap.cluster.x-k8s.io/v1beta1
kind: KubeadmConfigTemplate
metadata:
  name: {{ include "openstack-cluster.nodegroup.kct.name" (list $ $nodeGroup) }}
  labels:
    {{- include "openstack-cluster.componentLabels" (list $ "worker") | nindent 4 }}
    capi.stackhpc.com/node-group: {{ $nodeGroup.name }}
  annotations:
    capi.stackhpc.com/template-checksum: {{ include "openstack-cluster.nodegroup.kct.checksum" (list $ $nodeGroup) }}
    # We let Cluster API clean up the cluster resources
    # Deleting them ourselves, which CAPI is not expecting, can cause some nasty race conditions
    helm.sh/resource-policy: keep
spec:
  template:
    spec: {{ include "openstack-cluster.nodegroup.kct.spec" (list $ $nodeGroup) | nindent 6 }}
{{- end }}