feat: add a controller to label Nodes with PD compatibility labels

Dockerfile.node-labeler

@@ -0,0 +1,29 @@
+# Copyright 2025 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+FROM --platform=$BUILDPLATFORM golang:1.25.5 AS builder
+
+ARG STAGINGVERSION
+ARG TARGETPLATFORM
+
+WORKDIR /go/src/sigs.k8s.io/gcp-compute-persistent-disk-csi-driver
+ADD . .
+RUN GOARCH=$(echo $TARGETPLATFORM | cut -f2 -d '/') GCE_PD_CSI_STAGING_VERSION=$STAGINGVERSION make gce-pd-node-labeler
+
+FROM gcr.io/distroless/static:nonroot
+WORKDIR /
+COPY --from=builder /go/src/sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/bin/gce-pd-node-labeler .
+USER 65532:65532
+
+ENTRYPOINT ["/gce-pd-node-labeler"]

Makefile

@@ -18,7 +18,9 @@ REV=$(shell git describe --long --tags --match='v*' --dirty 2>/dev/null || git r
 GCE_PD_CSI_STAGING_VERSION ?= ${REV}
 STAGINGVERSION=${GCE_PD_CSI_STAGING_VERSION}
 STAGINGIMAGE=${GCE_PD_CSI_STAGING_IMAGE}
+LABELERSTAGINGIMAGE?=${STAGINGIMAGE}/gce-pd-node-labeler
 DRIVERBINARY=gce-pd-csi-driver
+LABELERBINARY=gce-pd-node-labeler
 DRIVERWINDOWSBINARY=${DRIVERBINARY}.exe
 
 DOCKER=DOCKER_CLI_EXPERIMENTAL=enabled docker
@@ -40,6 +42,10 @@ gce-pd-driver: require-GCE_PD_CSI_STAGING_VERSION
 	mkdir -p bin
 	CGO_ENABLED=0 go build -mod=vendor -gcflags=$(GCFLAGS) -ldflags "-extldflags=static -X main.version=$(STAGINGVERSION)" -o bin/${DRIVERBINARY} ./cmd/gce-pd-csi-driver/
 
+gce-pd-node-labeler: require-GCE_PD_CSI_STAGING_VERSION
+	mkdir -p bin
+	CGO_ENABLED=0 go build -mod=vendor -gcflags=$(GCFLAGS) -ldflags "-extldflags=static -X main.version=$(STAGINGVERSION)" -o bin/${LABELERBINARY} ./cmd/gce-pd-node-labeler/
+
 gce-pd-driver-windows: require-GCE_PD_CSI_STAGING_VERSION
 ifeq (${GOARCH}, amd64)
 	mkdir -p bin
@@ -111,6 +117,18 @@ build-and-push-container-linux-arm64: require-GCE_PD_CSI_STAGING_IMAGE init-buil
 		--build-arg BUILDPLATFORM=linux \
 		--build-arg STAGINGVERSION=$(STAGINGVERSION) --push --provenance=false .
 
+build-node-labeler-container-linux-amd64: require-GCE_PD_CSI_STAGING_IMAGE init-buildx
+	$(DOCKER) buildx build --file=Dockerfile.node-labeler --platform=linux/amd64 \
+		-t $(LABELERSTAGINGIMAGE):$(STAGINGVERSION)_linux_amd64 \
+		--build-arg BUILDPLATFORM=linux \
+		--build-arg STAGINGVERSION=$(STAGINGVERSION) --push --provenance=false .
+
+build-node-labeler-container-linux-arm64: require-GCE_PD_CSI_STAGING_IMAGE init-buildx
+	$(DOCKER) buildx build --file=Dockerfile.node-labeler --platform=linux/arm64 \
+		-t $(LABELERSTAGINGIMAGE):$(STAGINGVERSION)_linux_arm64 \
+		--build-arg BUILDPLATFORM=linux \
+		--build-arg STAGINGVERSION=$(STAGINGVERSION) --push --provenance=false .
+
 build-and-push-container-linux-debug: require-GCE_PD_CSI_STAGING_IMAGE init-buildx
 	$(DOCKER) buildx build --file=Dockerfile.debug --platform=linux \
 		-t $(STAGINGIMAGE):$(STAGINGVERSION)_linux \

cmd/gce-pd-node-labeler/main.go

@@ -0,0 +1,126 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package main is the GCE PD Node Labeler entrypoint.
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/klog/v2"
+	"sigs.k8s.io/controller-runtime/pkg/builder"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/client/config"
+	"sigs.k8s.io/controller-runtime/pkg/handler"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+	"sigs.k8s.io/controller-runtime/pkg/manager/signals"
+	"sigs.k8s.io/controller-runtime/pkg/predicate"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+	"sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/pkg/nodelabeler"
+)
+
+var (
+	configmapName      = flag.String("configmap-name", "machine-pd-compatibility", "Name of the ConfigMap to use for machine & PD compatibility information.")
+	configmapNamespace = flag.String("configmap-namespace", "gce-pd-csi-driver", "Namespace of the ConfigMap to use for machine & PD compatibility information.")
+)
+
+func main() {
+	klog.InitFlags(nil)
+	flag.Parse()
+	log.SetLogger(klog.NewKlogr())
+
+	ctx := signals.SetupSignalHandler()
+
+	mgr, err := manager.New(config.GetConfigOrDie(), manager.Options{})
+	if err != nil {
+		klog.Fatalf("Failed to create manager: %v", err)
+	}
+
+	reconciler := &nodelabeler.Reconciler{
+		Client:             mgr.GetClient(),
+		ConfigMapName:      *configmapName,
+		ConfigMapNamespace: *configmapNamespace,
+	}
+
+	if err := mgr.Add(manager.RunnableFunc(func(ctx context.Context) error {
+		if !mgr.GetCache().WaitForCacheSync(ctx) {
+			return errors.New("failed to wait for cache sync")
+		}
+		if err := reconciler.UpdateMachinePDCompatibility(ctx); err != nil {
+			klog.Errorf("Failed to load initial machine and PD compatibility map: %v", err)
+			return err
+		}
+		return nil
+	})); err != nil {
+		klog.Fatalf("Failed to add runnable to manager: %v", err)
+	}
+
+	mapFn := func(ctx context.Context, obj client.Object) []reconcile.Request {
+		cm, ok := obj.(*corev1.ConfigMap)
+		if !ok {
+			klog.Errorf("Expected a ConfigMap object but got %T", obj)
+			return nil
+		}
+		if err := reconciler.UpdateMachinePDCompatibility(ctx); err != nil {
+			klog.Errorf("Failed to update disk compatibility map from ConfigMap %s/%s: %v", cm.Namespace, cm.Name, err)
+			return nil
+		}
+
+		var nodes corev1.NodeList
+		if err := mgr.GetClient().List(ctx, &nodes); err != nil {
+			klog.Errorf("Failed to list nodes for configmap change reconciliation: %v", err)
+			return nil
+		}
+		requests := make([]reconcile.Request, len(nodes.Items))
+		for i, node := range nodes.Items {
+			requests[i] = reconcile.Request{
+				NamespacedName: types.NamespacedName{
+					Name: node.Name,
+				},
+			}
+		}
+		klog.Infof("ConfigMap changed, enqueuing reconciliation for %d nodes", len(requests))
+		return requests
+	}
+
+	err = builder.ControllerManagedBy(mgr).
+		For(&corev1.Node{}).
+		Watches(
+			&corev1.ConfigMap{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      *configmapName,
+					Namespace: *configmapNamespace,
+				},
+			},
+			handler.EnqueueRequestsFromMapFunc(mapFn),
+			builder.WithPredicates(predicate.NewPredicateFuncs(func(obj client.Object) bool {
+				return obj.GetName() == *configmapName && obj.GetNamespace() == *configmapNamespace
+			})),
+		).
+		Complete(reconciler)
+	if err != nil {
+		klog.Fatalf("Failed to build controller: %v", err)
+	}
+
+	klog.Info("Starting manager")
+	if err := mgr.Start(ctx); err != nil {
+		klog.Fatalf("Failed to start manager: %v", err)
+	}
+}