rbd: return group not found error for Get,Delete RPC calls

We should return NotFound status if the group doesn't exists
for ControllerGetVolumeGroup RPC call.
And, an empty/OK response for DeleteVolumeGroup if the group
doesn't exists

Signed-off-by: Nikhil-Ladha <nikhilladha1999@gmail.com>

Author: Nikhil-Ladha

internal/csi-addons/rbd/volumegroup.go

@@ -22,6 +22,7 @@ import (
 	"slices"
 
 	"github.com/ceph/ceph-csi/internal/rbd"
+	"github.com/ceph/ceph-csi/internal/rbd/group"
 	"github.com/ceph/ceph-csi/internal/rbd/types"
 	"github.com/ceph/ceph-csi/internal/util/log"
 
@@ -192,6 +193,10 @@ func (vs *VolumeGroupServer) DeleteVolumeGroup(
 	// resolve the volume group
 	vg, err := mgr.GetVolumeGroupByID(ctx, req.GetVolumeGroupId())
 	if err != nil {
+		if err == group.ErrRBDGroupNotFound {
+			log.DebugLog(ctx, "VolumeGroup %q doesn't exists", req.GetVolumeGroupId())
+			return &volumegroup.DeleteVolumeGroupResponse{}, nil
+		}
 		return nil, status.Errorf(
 			codes.NotFound,
 			"could not find volume group %q: %s",

internal/rbd/group/volume_group.go

@@ -31,7 +31,10 @@ import (
 	"github.com/ceph/ceph-csi/internal/util/log"
 )
 
-var ErrRBDGroupNotConnected = errors.New("RBD group is not connected")
+var (
+	ErrRBDGroupNotConnected = errors.New("RBD group is not connected")
+	ErrRBDGroupNotFound     = errors.New("RBD group not found")
+)
 
 // volumeGroup handles all requests for 'rbd group' operations.
 type volumeGroup struct {
@@ -82,6 +85,11 @@ func GetVolumeGroup(
 		return nil, fmt.Errorf("failed to get volume attributes for id %q: %w", vg, err)
 	}
 
+	if attrs.GroupName == "" || attrs.CreationTime == nil {
+		log.ErrorLog(ctx, "volume group with id %v not found", id)
+		return nil, ErrRBDGroupNotFound
+	}
+
 	var volumes []types.Volume
 	// it is needed to free the previously allocated volumes
 	defer func() {