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 # Licensed under the Academic Free License version 2.1
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU Library General Public License as published by
   9 # the Free Software Foundation; either version 2.1 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU Library General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU Library General Public License
  18 # along with this program; if not, write to the Free Software
  19 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20
  21 import gobject
  22 import dbus.service
  23
  24 class ExportedGObjectType(gobject.GObjectMeta, dbus.service.InterfaceType):
  25     """A metaclass which inherits from both GObjectMeta and
  26     `dbus.service.InterfaceType`. Used as the metaclass for `ExportedGObject`.
  27     """
  28     def __init__(cls, name, bases, dct):
  29         gobject.GObjectMeta.__init__(cls, name, bases, dct)
  30         dbus.service.InterfaceType.__init__(cls, name, bases, dct)
  31
  32 class ExportedGObject(gobject.GObject, dbus.service.Object):
  33     """A GObject which is exported on the D-Bus.
  34
  35     Because GObject and `dbus.service.Object` both have custom metaclasses,
  36     the naive approach using simple multiple inheritance won't work. This
  37     class has `ExportedGObjectType` as its metaclass, which is sufficient
  38     to make it work correctly.
  39     """
  40     __metaclass__ = ExportedGObjectType
  41
  42     def __init__(self, conn=None, object_path=None, **kwargs):
  43         """Initialize an exported GObject.
  44
  45         :Parameters:
  46             `conn` : dbus.connection.Connection
  47                 The D-Bus connection or bus
  48             `object_path` : str
  49                 The object path at which to register this object.
  50         :Keywords:
  51             `bus_name` : dbus.service.BusName
  52                 A bus name to be held on behalf of this object, or None.
  53             `gobject_properties` : dict
  54                 GObject properties to be set on the constructed object.
  55
  56                 Any unrecognised keyword arguments will also be interpreted
  57                 as GObject properties.
  58             """
  59         bus_name = kwargs.pop('bus_name', None)
  60         gobject_properties = kwargs.pop('gobject_properties', None)
  61
  62         if gobject_properties is not None:
  63             kwargs.update(gobject_properties)
  64         gobject.GObject.__init__(self, **kwargs)
  65         dbus.service.Object.__init__(self, conn=conn,
  66                                      object_path=object_path,
  67                                      bus_name=bus_name)