rbd: implement GetSnapshot CSI procedure

See-also: container-storage-interface/spec#586
Signed-off-by: Niels de Vos <ndevos@ibm.com>

Author: nixpanic

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/sts v1.33.19
 	github.com/ceph/ceph-csi/api v0.0.0-00010101000000-000000000000
 	github.com/ceph/go-ceph v0.33.0
-	github.com/container-storage-interface/spec v1.11.0
+	github.com/container-storage-interface/spec v1.11.1-0.20250515121015-a539b4f9fe41
 	github.com/csi-addons/kubernetes-csi-addons v0.12.0
 	github.com/csi-addons/spec v0.2.1-0.20241104111131-27825f744db5
 	github.com/gemalto/kmip-go v0.0.10

go.sum

@@ -157,8 +157,8 @@ github.com/cncf/xds/go v0.0.0-20210805033703-aa0b78936158/go.mod h1:eXthEFrGJvWH
 github.com/cncf/xds/go v0.0.0-20210922020428-25de7278fc84/go.mod h1:eXthEFrGJvWHgFFCl3hGmgk+/aYT6PnTQLykKQRLhEs=
 github.com/cncf/xds/go v0.0.0-20211001041855-01bcc9b48dfe/go.mod h1:eXthEFrGJvWHgFFCl3hGmgk+/aYT6PnTQLykKQRLhEs=
 github.com/cncf/xds/go v0.0.0-20211011173535-cb28da3451f1/go.mod h1:eXthEFrGJvWHgFFCl3hGmgk+/aYT6PnTQLykKQRLhEs=
-github.com/container-storage-interface/spec v1.11.0 h1:H/YKTOeUZwHtyPOr9raR+HgFmGluGCklulxDYxSdVNM=
-github.com/container-storage-interface/spec v1.11.0/go.mod h1:DtUvaQszPml1YJfIK7c00mlv6/g4wNMLanLgiUbKFRI=
+github.com/container-storage-interface/spec v1.11.1-0.20250515121015-a539b4f9fe41 h1:7+UfUxukJlnEVGALQzUcCYXP/ISyS/VZJ7DPpAQxROY=
+github.com/container-storage-interface/spec v1.11.1-0.20250515121015-a539b4f9fe41/go.mod h1:DtUvaQszPml1YJfIK7c00mlv6/g4wNMLanLgiUbKFRI=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/csi-addons/kubernetes-csi-addons v0.12.0 h1:RbF2dCjWV4ljynibEOkA0wbwwt/09awjOKgEFC14Bns=
 github.com/csi-addons/kubernetes-csi-addons v0.12.0/go.mod h1:8vrXJUZrlI2ms2aZ6qRfp8ieRlpHEefTX5azOFi67o0=

internal/rbd/controllerserver.go

@@ -1709,3 +1709,27 @@ func (cs *ControllerServer) ControllerUnpublishVolume(
 
 	return &csi.ControllerUnpublishVolumeResponse{}, nil
 }
+
+func (cs *ControllerServer) GetSnapshot(
+	ctx context.Context,
+	req *csi.GetSnapshotRequest,
+) (*csi.GetSnapshotResponse, error) {
+	mgr := NewManager(cs.Driver.GetInstanceID(), nil, req.GetSecrets())
+	defer mgr.Destroy(ctx)
+
+	snapID := req.GetSnapshotId()
+	snapshot, err := mgr.GetSnapshotByID(ctx, snapID)
+	if err != nil {
+		return nil, status.Errorf(codes.NotFound, "failed to find snapshot with ID %q: %s", snapID, err.Error())
+	}
+	defer snapshot.Destroy(ctx)
+
+	csiSnap, err := snapshot.ToCSI(ctx)
+	if err != nil {
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	return &csi.GetSnapshotResponse{
+		Snapshot: csiSnap,
+	}, nil
+}

internal/rbd/driver/driver.go

@@ -112,6 +112,7 @@ func (r *Driver) Run(conf *util.Config) {
 			csi.ControllerServiceCapability_RPC_CREATE_DELETE_SNAPSHOT,
 			csi.ControllerServiceCapability_RPC_CLONE_VOLUME,
 			csi.ControllerServiceCapability_RPC_EXPAND_VOLUME,
+			csi.ControllerServiceCapability_RPC_GET_SNAPSHOT,
 		})
 		// We only support the multi-writer option when using block, but it's a supported capability for the plugin in
 		// general