disable k8s node cleanup and let CAPI handle it (#32)

pkg/ck8s/api/annotations.go

@@ -0,0 +1,8 @@
+package apiv1
+
+const (
+	// AnnotationSkipCleanupKubernetesNodeOnRemove if set, only the microcluster & file cleanup is done.
+	// This is useful, if an external controller (e.g. CAPI) is responsible for the Kubernetes node life cycle.
+	// By default, the Kubernetes node is removed by k8sd if a node is removed from the cluster.
+	AnnotationSkipCleanupKubernetesNodeOnRemove = "k8sd/v1alpha/lifecycle/skip-cleanup-kubernetes-node-on-remove"
+)

pkg/ck8s/config_init.go

@@ -81,6 +81,12 @@ func GenerateInitControlPlaneConfig(cfg InitControlPlaneConfig) (apiv1.Bootstrap
 	// annotations
 	out.ClusterConfig.Annotations = cfg.InitConfig.Annotations
 
+	// Since CAPI handles the lifecycle management of Kubernetes nodes, k8s-snap should only focus on
+	// cleaning up microcluster and files during upgrades.
+	if _, ok := out.ClusterConfig.Annotations[apiv1.AnnotationSkipCleanupKubernetesNodeOnRemove]; !ok {
+		out.ClusterConfig.Annotations[apiv1.AnnotationSkipCleanupKubernetesNodeOnRemove] = "true"
+	}
+
 	// features
 	out.ClusterConfig.DNS.Enabled = ptr.To(cfg.InitConfig.GetEnableDefaultDNS())
 	out.ClusterConfig.LocalStorage.Enabled = ptr.To(cfg.InitConfig.GetEnableDefaultLocalStorage())