dbus/gobject_service.py

   1 """Support code for implementing D-Bus services via GObjects."""
   2
   3 # Copyright (C) 2007 Collabora Ltd. <http://www.collabora.co.uk/>
   4 #
   5 # Permission is hereby granted, free of charge, to any person
   6 # obtaining a copy of this software and associated documentation
   7 # files (the "Software"), to deal in the Software without
   8 # restriction, including without limitation the rights to use, copy,
   9 # modify, merge, publish, distribute, sublicense, and/or sell copies
  10 # of the Software, and to permit persons to whom the Software is
  11 # furnished to do so, subject to the following conditions:
  12 #
  13 # The above copyright notice and this permission notice shall be
  14 # included in all copies or substantial portions of the Software.
  15 #
  16 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17 # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18 # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19 # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  20 # HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  21 # WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  23 # DEALINGS IN THE SOFTWARE.
  24
  25 import gobject
  26 import dbus.service
  27
  28 class ExportedGObjectType(gobject.GObjectMeta, dbus.service.InterfaceType):
  29     """A metaclass which inherits from both GObjectMeta and
  30     `dbus.service.InterfaceType`. Used as the metaclass for `ExportedGObject`.
  31     """
  32     def __init__(cls, name, bases, dct):
  33         gobject.GObjectMeta.__init__(cls, name, bases, dct)
  34         dbus.service.InterfaceType.__init__(cls, name, bases, dct)
  35
  36 class ExportedGObject(gobject.GObject, dbus.service.Object):
  37     """A GObject which is exported on the D-Bus.
  38
  39     Because GObject and `dbus.service.Object` both have custom metaclasses,
  40     the naive approach using simple multiple inheritance won't work. This
  41     class has `ExportedGObjectType` as its metaclass, which is sufficient
  42     to make it work correctly.
  43     """
  44     __metaclass__ = ExportedGObjectType
  45
  46     def __init__(self, conn=None, object_path=None, **kwargs):
  47         """Initialize an exported GObject.
  48
  49         :Parameters:
  50             `conn` : dbus.connection.Connection
  51                 The D-Bus connection or bus
  52             `object_path` : str
  53                 The object path at which to register this object.
  54         :Keywords:
  55             `bus_name` : dbus.service.BusName
  56                 A bus name to be held on behalf of this object, or None.
  57             `gobject_properties` : dict
  58                 GObject properties to be set on the constructed object.
  59
  60                 Any unrecognised keyword arguments will also be interpreted
  61                 as GObject properties.
  62             """
  63         bus_name = kwargs.pop('bus_name', None)
  64         gobject_properties = kwargs.pop('gobject_properties', None)
  65
  66         if gobject_properties is not None:
  67             kwargs.update(gobject_properties)
  68         gobject.GObject.__init__(self, **kwargs)
  69         dbus.service.Object.__init__(self, conn=conn,
  70                                      object_path=object_path,
  71                                      bus_name=bus_name)