Add support for DeviceVlan

Device.go

@@ -77,6 +77,8 @@ func DeviceFactory(objectPath dbus.ObjectPath) (Device, error) {
 		return NewDeviceWired(objectPath)
 	case NmDeviceTypeWifi:
 		return NewDeviceWireless(objectPath)
+	case NmDeviceTypeVlan:
+		return NewDeviceVlan(objectPath)
 	}
 
 	return d, nil

DeviceVlan.go

@@ -0,0 +1,69 @@
+package gonetworkmanager
+
+import (
+	"encoding/json"
+
+	"github.com/godbus/dbus/v5"
+)
+
+const (
+	DeviceVlanInterface = DeviceInterface + ".Vlan"
+
+	// Properties
+	DeviceVlanPropertyCarrier = DeviceVlanInterface + ".Carrier" // readable  b
+	DeviceVlanPropertyParent  = DeviceVlanInterface + ".Parent"  // readable	o
+	DeviceVlanPropertyVlanId  = DeviceVlanInterface + ".VlanId"  // readable	u
+)
+
+// DeviceVlan Virtual LAN Device
+type DeviceVlan interface {
+	Device
+
+	// GetPropertyCarrier Indicates whether the physical carrier is found (e.g. whether a cable is plugged in or not).
+	// DEPRECATED: check for the "carrier" flag in the "InterfaceFlags" property on the "org.freedesktop.NetworkManager.Device" interface.
+	GetPropertyCarrier() (bool, error)
+
+	// GetPropertyParent The object path of the parent device.
+	GetPropertyParent() (Device, error)
+
+	// GetPropertyVlanId The VLAN ID of this VLAN interface
+	GetPropertyVlanId() (uint32, error)
+}
+
+func NewDeviceVlan(objectPath dbus.ObjectPath) (DeviceVlan, error) {
+	var d deviceVlan
+	return &d, d.init(NetworkManagerInterface, objectPath)
+}
+
+type deviceVlan struct {
+	device
+}
+
+func (d *deviceVlan) GetPropertyParent() (Device, error) {
+	path, err := d.getObjectProperty(DeviceVlanPropertyParent)
+	if err != nil || path == "/" {
+		return nil, err
+	}
+	return DeviceFactory(path)
+}
+
+func (d *deviceVlan) GetPropertyVlanId() (uint32, error) {
+	return d.getUint32Property(DeviceVlanPropertyVlanId)
+}
+
+func (d *deviceVlan) GetPropertyCarrier() (bool, error) {
+	return d.getBoolProperty(DeviceVlanPropertyCarrier)
+}
+
+func (d *deviceVlan) MarshalJSON() ([]byte, error) {
+	m, err := d.device.marshalMap()
+	if err != nil {
+		return nil, err
+	}
+
+	m["HwAddress"], _ = d.GetPropertyHwAddress()
+	m["Parent"], _ = d.GetPropertyParent()
+	m["Carrier"], _ = d.GetPropertyCarrier()
+	m["VlanId"], _ = d.GetPropertyVlanId()
+	return json.Marshal(m)
+}