util: add helper for group controller

Added helper function to add the group
controller capabilities which needs to
be included by csi driver that wants to
implement group controller.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

internal/csi-common/driver.go

@@ -33,6 +33,7 @@ type CSIDriver struct {
 	// topology constraints that this nodeserver will advertise
 	topology          map[string]string
 	capabilities      []*csi.ControllerServiceCapability
+	groupCapabilities []*csi.GroupControllerServiceCapability
 	vc                []*csi.VolumeCapability_AccessMode
 }
 
@@ -116,3 +117,16 @@ func (d *CSIDriver) AddVolumeCapabilityAccessModes(
 func (d *CSIDriver) GetVolumeCapabilityAccessModes() []*csi.VolumeCapability_AccessMode {
 	return d.vc
 }
+
+// AddControllerServiceCapabilities stores the group controller capabilities
+// in driver object.
+func (d *CSIDriver) AddGroupControllerServiceCapabilities(cl []csi.GroupControllerServiceCapability_RPC_Type) {
+	csc := make([]*csi.GroupControllerServiceCapability, 0, len(cl))
+
+	for _, c := range cl {
+		log.DefaultLog("Enabling group controller service capability: %v", c.String())
+		csc = append(csc, NewGroupControllerServiceCapability(c))
+	}
+
+	d.groupCapabilities = csc
+}

internal/csi-common/utils.go

@@ -95,6 +95,18 @@ func NewControllerServiceCapability(ctrlCap csi.ControllerServiceCapability_RPC_
 	}
 }
 
+// NewGroupControllerServiceCapability returns group controller capabilities.
+func NewGroupControllerServiceCapability(ctrlCap csi.GroupControllerServiceCapability_RPC_Type,
+) *csi.GroupControllerServiceCapability {
+	return &csi.GroupControllerServiceCapability{
+		Type: &csi.GroupControllerServiceCapability_Rpc{
+			Rpc: &csi.GroupControllerServiceCapability_RPC{
+				Type: ctrlCap,
+			},
+		},
+	}
+}
+
 // NewMiddlewareServerOption creates a new grpc.ServerOption that configures a
 // common format for log messages and other gRPC related handlers.
 func NewMiddlewareServerOption() grpc.ServerOption {