From 8678ea28ee0910e8b84665fe0bd6ebd7238d119b Mon Sep 17 00:00:00 2001
From: Felix Prasse <1330854+flx5@users.noreply.github.com>
Date: Thu, 22 May 2025 21:05:24 +0200
Subject: [PATCH] Keep manager label for VSC

If distributed snapshotting is enabled in the external snapshotter a manager label is added to the volume snapshot content. When exposing the snapshot velero needs to keep this label around otherwise the exposed snapshot will never become ready.

Signed-off-by: Felix Prasse <1330854+flx5@users.noreply.github.com>
---
 changelogs/unreleased/8969-flx5  |  1 +
 pkg/exposer/csi_snapshot.go      | 12 ++++++++++++
 pkg/exposer/csi_snapshot_test.go | 24 ++++++++++++++++++++++++
 3 files changed, 37 insertions(+)
 create mode 100644 changelogs/unreleased/8969-flx5

diff --git a/changelogs/unreleased/8969-flx5 b/changelogs/unreleased/8969-flx5
new file mode 100644
index 000000000..683f437a4
--- /dev/null
+++ b/changelogs/unreleased/8969-flx5
@@ -0,0 +1 @@
+Add support for [distributed snapshotting](https://github.com/kubernetes-csi/external-snapshotter/tree/4cedb3f45790ac593ebfa3324c490abedf739477?tab=readme-ov-file#distributed-snapshotting)
\ No newline at end of file
diff --git a/pkg/exposer/csi_snapshot.go b/pkg/exposer/csi_snapshot.go
index bee42a61c..9fb4e42e0 100644
--- a/pkg/exposer/csi_snapshot.go
+++ b/pkg/exposer/csi_snapshot.go
@@ -446,6 +446,7 @@ func (e *csiSnapshotExposer) createBackupVSC(ctx context.Context, ownerObject co
 		ObjectMeta: metav1.ObjectMeta{
 			Name:        backupVSCName,
 			Annotations: snapshotVSC.Annotations,
+			Labels:      map[string]string{},
 		},
 		Spec: snapshotv1api.VolumeSnapshotContentSpec{
 			VolumeSnapshotRef: corev1api.ObjectReference{
@@ -463,6 +464,17 @@ func (e *csiSnapshotExposer) createBackupVSC(ctx context.Context, ownerObject co
 		},
 	}
 
+	/*
+		We need to keep the label of the managing node for distributed snapshots.
+		The external snapshot manager will only manage snapshots matching it's node if that feature is enabled.
+
+		https://github.com/kubernetes-csi/external-snapshotter/tree/4cedb3f45790ac593ebfa3324c490abedf739477?tab=readme-ov-file#distributed-snapshotting
+		https://github.com/kubernetes-csi/external-snapshotter/blob/4cedb3f45790ac593ebfa3324c490abedf739477/pkg/utils/util.go#L158
+	*/
+	if manager, ok := snapshotVSC.Labels["snapshot.storage.kubernetes.io/managed-by"]; ok {
+		vsc.ObjectMeta.Labels["snapshot.storage.kubernetes.io/managed-by"] = manager
+	}
+
 	return e.csiSnapshotClient.VolumeSnapshotContents().Create(ctx, vsc, metav1.CreateOptions{})
 }
 
diff --git a/pkg/exposer/csi_snapshot_test.go b/pkg/exposer/csi_snapshot_test.go
index 223a85773..09fb91ff2 100644
--- a/pkg/exposer/csi_snapshot_test.go
+++ b/pkg/exposer/csi_snapshot_test.go
@@ -129,6 +129,11 @@ func TestExpose(t *testing.T) {
 		},
 	}
 
+	vscObjWithLabels := vscObj
+	vscObjWithLabels.Labels = map[string]string{
+		"snapshot.storage.kubernetes.io/managed-by": "worker",
+	}
+
 	daemonSet := &appsv1api.DaemonSet{
 		ObjectMeta: metav1.ObjectMeta{
 			Namespace: "velero",
@@ -370,6 +375,24 @@ func TestExpose(t *testing.T) {
 				daemonSet,
 			},
 		},
+		{
+			name:        "success-with-labels",
+			ownerBackup: backup,
+			exposeParam: CSISnapshotExposeParam{
+				SnapshotName:     "fake-vs",
+				SourceNamespace:  "fake-ns",
+				AccessMode:       AccessModeFileSystem,
+				OperationTimeout: time.Millisecond,
+				ExposeTimeout:    time.Millisecond,
+			},
+			snapshotClientObj: []runtime.Object{
+				vsObject,
+				vscObjWithLabels,
+			},
+			kubeClientObj: []runtime.Object{
+				daemonSet,
+			},
+		},
 		{
 			name:        "restore size from exposeParam",
 			ownerBackup: backup,
@@ -650,6 +673,7 @@ func TestExpose(t *testing.T) {
 				assert.Equal(t, expectedVSC.Name, *expectedVS.Spec.Source.VolumeSnapshotContentName)
 
 				assert.Equal(t, expectedVSC.Annotations, vscObj.Annotations)
+				assert.Equal(t, expectedVSC.Labels, vscObj.Labels)
 				assert.Equal(t, expectedVSC.Spec.DeletionPolicy, vscObj.Spec.DeletionPolicy)
 				assert.Equal(t, expectedVSC.Spec.Driver, vscObj.Spec.Driver)
 				assert.Equal(t, *expectedVSC.Spec.VolumeSnapshotClassName, *vscObj.Spec.VolumeSnapshotClassName)