Delete all PVCs if guest cluster is deleted in Rancher

If a cluster is deleted, the PVCs of the workloads are not deleted in Harvester. This is because the node driver does not know why the associated VM has to be deleted, e.g. because its parameters have changed or because the cluster is deleted.

To solve the problem, a finalizer on the Machine resource in Rancher will add an annotation to the VM which then is evaluated by the node driver when it running the Remove() handler.

Signed-off-by: Volker Theile <vtheile@suse.com>

harvester/harvester.go

@@ -23,6 +23,8 @@ const (
 	actionStart   = "start"
 	actionStop    = "stop"
 	actionRestart = "restart"
+
+	removeAllPVCsAnnotationKey = "harvesterhci.io/removeAllPersistentVolumeClaims"
 )
 
 // Driver is the driver used when no driver is selected. It is used to
@@ -180,9 +182,16 @@ func (d *Driver) Remove() error {
 		}
 		return err
 	}
+
+	removeAll := false
+	if value, ok := vm.Annotations[removeAllPVCsAnnotationKey]; ok && value == "true" {
+		log.Debugf("Force the removal of all persistent volume claims")
+		removeAll = true
+	}
+
 	removedPVCs := make([]string, 0, len(vm.Spec.Template.Spec.Volumes))
 	for _, volume := range vm.Spec.Template.Spec.Volumes {
-		if volume.PersistentVolumeClaim == nil || volume.PersistentVolumeClaim.Hotpluggable {
+		if volume.PersistentVolumeClaim == nil || (!removeAll && volume.PersistentVolumeClaim.Hotpluggable) {
 			continue
 		}
 		removedPVCs = append(removedPVCs, volume.PersistentVolumeClaim.ClaimName)