S3CSI-227: Move volumeID from Labels to Annotations and add cache volume context

pkg/driver/node/mounter/pod_unmounter.go

@@ -246,8 +246,13 @@ func (u *PodUnmounter) writeExitFile(podPath string) error {
 
 // cleanupCredentials removes credentials associated with the Mountpoint Pod
 func (u *PodUnmounter) cleanupCredentials(mpPod *corev1.Pod) error {
+	volumeID, exists := mpPod.Annotations[mppod.AnnotationVolumeId]
+	if !exists {
+		// Fallback to deprecated label for backward compatibility with older Mountpoint Pods
+		volumeID = mpPod.Labels[mppod.DeprecatedLabelVolumeId]
+	}
 	return u.credProvider.Cleanup(credentialprovider.CleanupContext{
-		VolumeID:  mpPod.Labels[mppod.LabelVolumeId],
+		VolumeID:  volumeID,
 		PodID:     string(mpPod.UID),
 		WritePath: mppod.PathOnHost(u.podPath(string(mpPod.UID)), mppod.KnownPathCredentials),
 		MountKind: credentialprovider.MountKindPod,

pkg/driver/node/mounter/pod_unmounter_test.go

@@ -285,7 +285,7 @@ func TestCleanupCredentials(t *testing.T) {
 					Name: "test-pod",
 					UID:  "test-uid",
 					Labels: map[string]string{
-						mppod.LabelVolumeId: "test-volume",
+						mppod.DeprecatedLabelVolumeId: "test-volume",
 					},
 				},
 			}
@@ -306,7 +306,7 @@ func TestCleanupDanglingMounts(t *testing.T) {
 				Name: name,
 				UID:  "test-uid",
 				Labels: map[string]string{
-					mppod.LabelVolumeId: "test-volume",
+					mppod.DeprecatedLabelVolumeId: "test-volume",
 				},
 			},
 		}
@@ -630,7 +630,7 @@ func TestCleanUnmount(t *testing.T) {
 				Name: "mp-test-pod",
 				UID:  "test-uid",
 				Labels: map[string]string{
-					mppod.LabelVolumeId: "test-volume",
+					mppod.DeprecatedLabelVolumeId: "test-volume",
 				},
 			},
 		}
@@ -824,7 +824,7 @@ func TestCleanUnmount(t *testing.T) {
 				Name: "mp-test-pod",
 				UID:  "test-uid",
 				Labels: map[string]string{
-					mppod.LabelVolumeId: "test-volume",
+					mppod.DeprecatedLabelVolumeId: "test-volume",
 				},
 			},
 		}
@@ -874,7 +874,7 @@ func TestCleanUnmount(t *testing.T) {
 				Name: "mp-test-pod",
 				UID:  "test-uid",
 				Labels: map[string]string{
-					mppod.LabelVolumeId: "test-volume",
+					mppod.DeprecatedLabelVolumeId: "test-volume",
 				},
 			},
 		}

pkg/driver/node/volumecontext/volume_context.go

@@ -4,6 +4,13 @@ package volumecontext
 const (
 	BucketName           = "bucketName"
 	AuthenticationSource = "authenticationSource"
+	STSRegion            = "stsRegion"
+
+	Cache                                = "cache"
+	CacheEmptyDirSizeLimit               = "cacheEmptyDirSizeLimit"
+	CacheEmptyDirMedium                  = "cacheEmptyDirMedium"
+	CacheEphemeralStorageClassName       = "cacheEphemeralStorageClassName"
+	CacheEphemeralStorageResourceRequest = "cacheEphemeralStorageResourceRequest"
 
 	MountpointPodServiceAccountName = "mountpointPodServiceAccountName"
 

pkg/podmounter/mppod/creator.go

@@ -17,8 +17,6 @@ import (
 // Labels populated on spawned Mountpoint Pods.
 const (
 	LabelMountpointVersion = constants.DriverName + "/mountpoint-version"
-	LabelPodUID            = constants.DriverName + "/pod-uid"
-	LabelVolumeName        = constants.DriverName + "/volume-name"
 	LabelCSIDriverVersion  = constants.DriverName + "/mounted-by-csi-driver-version"
 )
 
@@ -62,16 +60,23 @@ func (c *Creator) Create(pod *corev1.Pod, pv *corev1.PersistentVolume) *corev1.P
 	node := pod.Spec.NodeName
 	name := MountpointPodNameFor(string(pod.UID), pv.Name)
 
+	var volumeHandle string
+	if pv.Spec.CSI != nil {
+		volumeHandle = pv.Spec.CSI.VolumeHandle
+	}
+
 	mpPod := &corev1.Pod{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      name,
 			Namespace: c.config.Namespace,
 			Labels: map[string]string{
 				LabelMountpointVersion: c.config.MountpointVersion,
-				LabelPodUID:            string(pod.UID),
-				LabelVolumeName:        pv.Name,
 				LabelCSIDriverVersion:  c.config.CSIDriverVersion,
 			},
+			Annotations: map[string]string{
+				AnnotationVolumeName: pv.Name,
+				AnnotationVolumeId:   volumeHandle,
+			},
 		},
 		Spec: corev1.PodSpec{
 			// Mountpoint terminates with zero exit code on a successful termination,

pkg/podmounter/mppod/creator_test.go

@@ -51,10 +51,9 @@ func createAndVerifyPod(t *testing.T, clusterVariant cluster.Variant, expectedRu
 		assert.Equals(t, namespace, mpPod.Namespace)
 		assert.Equals(t, map[string]string{
 			mppod.LabelMountpointVersion: mountpointVersion,
-			mppod.LabelPodUID:            testPodUID,
-			mppod.LabelVolumeName:        testVolName,
 			mppod.LabelCSIDriverVersion:  csiDriverVersion,
 		}, mpPod.Labels)
+		assert.Equals(t, testVolName, mpPod.Annotations[mppod.AnnotationVolumeName])
 
 		assert.Equals(t, priorityClassName, mpPod.Spec.PriorityClassName)
 		assert.Equals(t, corev1.RestartPolicyOnFailure, mpPod.Spec.RestartPolicy)
@@ -202,6 +201,7 @@ func TestNewCreator(t *testing.T) {
 	assert.Equals(t, config.Namespace, mpPod.Namespace)
 	assert.Equals(t, config.MountpointVersion, mpPod.Labels[mppod.LabelMountpointVersion])
 	assert.Equals(t, config.CSIDriverVersion, mpPod.Labels[mppod.LabelCSIDriverVersion])
+	assert.Equals(t, "test-pv", mpPod.Annotations[mppod.AnnotationVolumeName])
 	assert.Equals(t, config.PriorityClassName, mpPod.Spec.PriorityClassName)
 	assert.Equals(t, config.Container.Image, mpPod.Spec.Containers[0].Image)
 	assert.Equals(t, config.Container.ImagePullPolicy, mpPod.Spec.Containers[0].ImagePullPolicy)

pkg/podmounter/mppod/mppod.go

@@ -14,12 +14,17 @@ const (
 	AnnotationNeedsUnmount = constants.DriverName + "/needs-unmount"
 	// AnnotationNoNewWorkload is the annotation used to prevent new workloads from being assigned
 	AnnotationNoNewWorkload = constants.DriverName + "/no-new-workload"
+	// AnnotationVolumeName stores the PV name as an annotation (no length limit unlike labels).
+	AnnotationVolumeName = constants.DriverName + "/volume-name"
+	// AnnotationVolumeId stores the volume ID as an annotation (no length limit unlike labels).
+	AnnotationVolumeId = constants.DriverName + "/volume-id"
 )
 
-// Pod labels
+// Deprecated Pod labels -- kept for backward compatibility with older Mountpoint Pods.
 const (
-	// LabelVolumeId is the label used to store the volume ID
-	LabelVolumeId = constants.DriverName + "/volume-id"
+	// DeprecatedLabelVolumeId is the deprecated label used to store the volume ID.
+	// Use AnnotationVolumeId instead. Labels are limited to 63 characters.
+	DeprecatedLabelVolumeId = constants.DriverName + "/volume-id"
 )
 
 // MountpointPodNameFor returns a consistent and unique Pod name for

tests/controller/controller_test.go

@@ -763,13 +763,12 @@ func expectNoMountpointPodFor(pod *testPod, vol *testVolume) {
 
 // expectNoMountpointPodForWorkloadPod verifies that there is no Mountpoint Pod scheduled for given `pod`.
 // `expectNoMountpointPodFor` is preferable to this method if the `vol` is known as this performs a slower list operation.
-func expectNoMountpointPodForWorkloadPod(pod *testPod) {
+// This lists all pods in the mountpoint namespace with the mountpoint-version label to find any mountpoint pods.
+func expectNoMountpointPodForWorkloadPod(_ *testPod) {
 	Consistently(func(g Gomega) {
 		podList := &corev1.PodList{}
 		g.Expect(k8sClient.List(ctx, podList,
-			client.InNamespace(mountpointNamespace), client.MatchingLabels{
-				mppod.LabelPodUID: string(pod.UID),
-			},
+			client.InNamespace(mountpointNamespace), client.HasLabels{mppod.LabelMountpointVersion},
 		)).To(Succeed())
 
 		g.Expect(podList.Items).To(BeEmpty(), "Expected empty list but got: %#v", podList)
@@ -786,9 +785,8 @@ func waitAndVerifyMountpointPodFor(pod *testPod, vol *testVolume) {
 // verifyMountpointPodFor verifies given `mountpointPod` for given `pod` and `vol`.
 func verifyMountpointPodFor(pod *testPod, vol *testVolume, mountpointPod *testPod) {
 	Expect(mountpointPod.ObjectMeta.Labels).To(HaveKeyWithValue(mppod.LabelMountpointVersion, mountpointVersion))
-	Expect(mountpointPod.ObjectMeta.Labels).To(HaveKeyWithValue(mppod.LabelPodUID, string(pod.UID)))
-	Expect(mountpointPod.ObjectMeta.Labels).To(HaveKeyWithValue(mppod.LabelVolumeName, vol.pvc.Spec.VolumeName))
 	Expect(mountpointPod.ObjectMeta.Labels).To(HaveKeyWithValue(mppod.LabelCSIDriverVersion, version.GetVersion().DriverVersion))
+	Expect(mountpointPod.ObjectMeta.Annotations).To(HaveKeyWithValue(mppod.AnnotationVolumeName, vol.pvc.Spec.VolumeName))
 
 	Expect(mountpointPod.Spec.RestartPolicy).To(Equal(corev1.RestartPolicyOnFailure))