Merge pull request #15650 from justinsb/prune_node_labels

Support removal of managed node labels

cmd/kops-controller/controllers/legacy_node_controller.go

@@ -132,12 +132,23 @@ func (r *LegacyNodeReconciler) Reconcile(ctx context.Context, req ctrl.Request)
 		}
 	}
 
-	if len(updateLabels) == 0 {
+	deleteLabels := make(map[string]struct{})
+	for k := range node.Labels {
+		// If it is one of our managed labels, "prune" values we don't want to be there
+		switch k {
+		case nodelabels.RoleLabelMaster16, nodelabels.RoleLabelAPIServer16, nodelabels.RoleLabelNode16, nodelabels.RoleLabelControlPlane20:
+			if _, found := labels[k]; !found {
+				deleteLabels[k] = struct{}{}
+			}
+		}
+	}
+
+	if len(updateLabels) == 0 && len(deleteLabels) == 0 {
 		klog.V(4).Infof("no label changes needed for %s", node.Name)
 		return ctrl.Result{}, nil
 	}
 
-	if err := patchNodeLabels(r.coreV1Client, ctx, node, updateLabels); err != nil {
+	if err := patchNodeLabels(r.coreV1Client, ctx, node, updateLabels, deleteLabels); err != nil {
 		klog.Warningf("failed to patch node labels on %s: %v", node.Name, err)
 		return ctrl.Result{}, err
 	}

cmd/kops-controller/controllers/node_controller.go

@@ -29,6 +29,7 @@ import (
 	corev1client "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/klog/v2"
 	"k8s.io/kops/pkg/nodeidentity"
+	"k8s.io/kops/pkg/nodelabels"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/manager"
@@ -99,12 +100,23 @@ func (r *NodeReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.
 		}
 	}
 
-	if len(updateLabels) == 0 {
+	deleteLabels := make(map[string]struct{})
+	for k := range node.Labels {
+		// If it is one of our managed labels, "prune" values we don't want to be there
+		switch k {
+		case nodelabels.RoleLabelMaster16, nodelabels.RoleLabelAPIServer16, nodelabels.RoleLabelNode16, nodelabels.RoleLabelControlPlane20:
+			if _, found := labels[k]; !found {
+				deleteLabels[k] = struct{}{}
+			}
+		}
+	}
+
+	if len(updateLabels) == 0 && len(deleteLabels) == 0 {
 		klog.V(4).Infof("no label changes needed for %s", node.Name)
 		return ctrl.Result{}, nil
 	}
 
-	if err := patchNodeLabels(r.coreV1Client, ctx, node, updateLabels); err != nil {
+	if err := patchNodeLabels(r.coreV1Client, ctx, node, updateLabels, deleteLabels); err != nil {
 		klog.Warningf("failed to patch node labels on %s: %v", node.Name, err)
 		return ctrl.Result{}, err
 	}
@@ -124,14 +136,22 @@ type nodePatch struct {
 }
 
 type nodePatchMetadata struct {
-	Labels map[string]string `json:"labels,omitempty"`
+	Labels map[string]*string `json:"labels,omitempty"`
 }
 
 // patchNodeLabels patches the node labels to set the specified labels
-func patchNodeLabels(client *corev1client.CoreV1Client, ctx context.Context, node *corev1.Node, setLabels map[string]string) error {
+func patchNodeLabels(client *corev1client.CoreV1Client, ctx context.Context, node *corev1.Node, setLabels map[string]string, deleteLabels map[string]struct{}) error {
 	nodePatchMetadata := &nodePatchMetadata{
-		Labels: setLabels,
+		Labels: make(map[string]*string),
 	}
+	for k, v := range setLabels {
+		v := v
+		nodePatchMetadata.Labels[k] = &v
+	}
+	for k := range deleteLabels {
+		nodePatchMetadata.Labels[k] = nil
+	}
+
 	nodePatch := &nodePatch{
 		Metadata: nodePatchMetadata,
 	}