# -*- coding: utf-8 -*-
# slip.dbus.service -- convenience functions for using dbus-activated
# services
#
# Copyright © 2008, 2009 Red Hat, Inc.
# Authors: Nils Philippsen <nils@redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""This module contains convenience functions for using dbus-activated services."""
import dbus
import dbus.service
from slip._wrappers import _gobject as GObject
import polkit
__all__ = ["Object", "InterfaceType", "set_mainloop"]
__mainloop__ = None
def __glib_quit_cb__():
global __mainloop__
# assume a Glib mainloop
__mainloop__.quit()
__quit_cb__ = __glib_quit_cb__
def set_mainloop(mainloop):
global __mainloop__
__mainloop__ = mainloop
def set_quit_cb(quit_cb):
global __quit_cb__
__quit_cb__ = quit_cb
def quit_cb():
global __quit_cb__
__quit_cb__()
SENDER_KEYWORD = "__slip_dbus_service_sender__"
ASYNC_CALLBACKS = ("__slip_dbus_service_reply_cb__",
"__slip_dbus_service_error_cb__")
def wrap_method(method):
global SENDER_KEYWORD
global ASYNC_CALLBACKS
if method._dbus_sender_keyword is not None:
sender_keyword = method._dbus_sender_keyword
hide_sender_keyword = False
else:
sender_keyword = SENDER_KEYWORD
hide_sender_keyword = True
if method._dbus_async_callbacks is not None:
async_callbacks = method._dbus_async_callbacks
method_is_async = True
else:
async_callbacks = ASYNC_CALLBACKS
method_is_async = False
hide_async_callbacks = not method_is_async
def wrapped_method(self, *p, **k):
sender = k.get(sender_keyword)
if sender is not None:
# i.e. called over the bus, not locally
reply_cb = k[async_callbacks[0]]
error_cb = k[async_callbacks[1]]
if hide_sender_keyword:
del k[sender_keyword]
if hide_async_callbacks:
del k[async_callbacks[0]]
del k[async_callbacks[1]]
self.sender_seen(sender)
action_id = getattr(method, "_slip_polkit_auth_required",
getattr(self, "default_polkit_auth_required",
None))
if sender is not None and action_id:
def reply_handler(is_auth):
if is_auth:
if method_is_async:
# k contains async callbacks, simply pass on reply_cb
# and error_cb
method(self, *p, **k)
else:
# execute the synchronous method ...
error = None
try:
result = method(self, *p, **k)
except Exception, e:
error = e
# ... and call the reply or error callback
if error:
error_cb(error)
else:
# reply_cb((None,)) != reply_cb()
if result is None:
reply_cb()
else:
reply_cb(result)
else:
error_cb(polkit.NotAuthorizedException(action_id))
self.timeout_restart()
def error_handler(error):
error_cb(error)
self.timeout_restart()
polkit.IsSystemBusNameAuthorizedAsync(sender, action_id,
reply_handler=reply_handler, error_handler=error_handler)
else:
# no action id, or run locally, no need to do anything fancy
retval = method(self, *p, **k)
self.timeout_restart()
return retval
for attr in filter(lambda x: x[:6] == "_dbus_", dir(method)):
if attr == "_dbus_sender_keyword":
wrapped_method._dbus_sender_keyword = sender_keyword
elif attr == "_dbus_async_callbacks":
wrapped_method._dbus_async_callbacks = async_callbacks
else:
setattr(wrapped_method, attr, getattr(method, attr))
# delattr (method, attr)
wrapped_method.func_name = method.func_name
return wrapped_method
class InterfaceType(dbus.service.InterfaceType):
def __new__(cls, name, bases, dct):
for (attrname, attr) in dct.iteritems():
if getattr(attr, "_dbus_is_method", False):
dct[attrname] = wrap_method(attr)
return super(InterfaceType, cls).__new__(cls, name, bases, dct)
class Object(dbus.service.Object):
__metaclass__ = InterfaceType
# timeout & persistence
persistent = False
default_duration = 5
duration = default_duration
current_source = None
senders = set()
connections_senders = {}
connections_smobjs = {}
# PolicyKit
default_polkit_auth_required = None
def __init__(self, conn=None, object_path=None, bus_name=None,
persistent=None):
super(Object, self).__init__(conn, object_path, bus_name)
if persistent == None:
self.persistent = self.__class__.persistent
else:
self.persistent = persistent
def _timeout_cb(self):
if not self.persistent and len(Object.senders) == 0:
quit_cb()
return False
Object.current_source = None
Object.duration = self.default_duration
return False
def _name_owner_changed(self, name, old_owner, new_owner):
conn = self.connection
if not new_owner and (old_owner, conn) in Object.senders:
Object.senders.remove((old_owner, conn))
Object.connections_senders[conn].remove(old_owner)
if len(Object.connections_senders[conn]) == 0:
Object.connections_smobjs[conn].remove()
del Object.connections_senders[conn]
del Object.connections_smobjs[conn]
if not self.persistent and len(Object.senders) == 0 and \
Object.current_source == None:
quit_cb()
def timeout_restart(self, duration=None):
if not duration:
duration = self.__class__.default_duration
if not Object.duration or duration > Object.duration:
Object.duration = duration
if not self.persistent or len(Object.senders) == 0:
if Object.current_source:
GObject.source_remove(Object.current_source)
Object.current_source = \
GObject.timeout_add(Object.duration * 1000,
self._timeout_cb)
def sender_seen(self, sender):
if (sender, self.connection) not in Object.senders:
Object.senders.add((sender, self.connection))
if self.connection not in Object.connections_senders.keys():
Object.connections_senders[self.connection] = set()
Object.connections_smobjs[self.connection] = \
self.connection.add_signal_receiver(
handler_function=self._name_owner_changed,
signal_name="NameOwnerChanged",
dbus_interface="org.freedesktop.DBus")
Object.connections_senders[self.connection].add(sender)