[kupfer] session: Implement modern Gnome Session D-Bus connection

[Ulrik Sverdrup <usverdrup src gnome org>]

commit 4cfdb01d8d0ed26f4bd1757037860b9c08c34e4e
Author: Ulrik Sverdrup <ulrik sverdrup gmail com>
Date:   Thu Sep 3 09:34:43 2009 +0200

    session: Implement modern Gnome Session D-Bus connection
    
    Try to connect with org.gnome.SessionManager before falling back to
    gnomeui.

 kupfer/session.py |  118 +++++++++++++++++++++++++++++++++++++++++++++--------
 1 files changed, 100 insertions(+), 18 deletions(-)
---
diff --git a/kupfer/session.py b/kupfer/session.py
index 03ada06..13e16e4 100644
--- a/kupfer/session.py
+++ b/kupfer/session.py
@@ -6,41 +6,123 @@ close, to be able to save state before being killed;
 the module API does not depend on the session API used
 """
 
+import os
+
+import dbus
 import gobject
-from . import pretty, version
 
-_has_gnomeui = False
-try:
-	import gnome
-	import gnome.ui
-except ImportError:
-	pass
-else:
-	_has_gnomeui = True
+from kupfer import pretty, version
 
 class SessionClient (gobject.GObject, pretty.OutputMixin):
 	"""Session handling controller
 
 	signals:
 	save-yourself: Program should save state
-	die:           Program should quit
+	die:           Program should quit immediately
 	"""
 	__gtype_name__ = "SessionClient"
 
 	def __init__(self):
 		"""Set up program as client to current Session"""
 		gobject.GObject.__init__(self)
-		if _has_gnomeui:
-			gnome.program_init(version.PACKAGE_NAME, version.VERSION)
-			client = gnome.ui.master_client()
-			client.connect("save-yourself", self._session_save)
-			client.connect("die", self._session_die)
-			self.output_debug("Setting up session connection using GnomeClient")
-		self._enabled = _has_gnomeui
+
+		succ = False
+		try:
+			succ = self._connect_session_manager()
+		except dbus.DBusException, exc:
+			self.output_error(exc)
+		if not succ:
+			succ = self._connect_gnomeui()
+
+		# unset autostart id so that it is not transferred
+		os.putenv("DESKTOP_AUTOSTART_ID", "")
+		self._enabled = succ
 		if not self.enabled:
 			self.output_info("Warning: Not able to connect to current \
 				desktop session, please Quit before logout to save \
-				kupfer's data. (Gnome-session 2.26 support is coming.)")
+				kupfer's data.")
+
+	def _connect_gnomeui(self):
+		try:
+			import gnome
+			import gnome.ui
+		except ImportError:
+			return False
+
+		gnome.program_init(version.PACKAGE_NAME, version.VERSION)
+		client = gnome.ui.master_client()
+		client.connect("save-yourself", self._session_save)
+		client.connect("die", self._session_die)
+		self.output_debug("Setting up session connection using GnomeClient")
+		return True
+
+	def _connect_session_manager(self):
+		bus = dbus.SessionBus()
+		proxy_obj = bus.get_object('org.freedesktop.DBus',
+				'/org/freedesktop/DBus')
+		dbus_iface = dbus.Interface(proxy_obj, 'org.freedesktop.DBus')
+		service_name = "org.gnome.SessionManager"
+		obj_name = "/org/gnome/SessionManager"
+		iface_name = service_name
+
+		if not dbus_iface.NameHasOwner(service_name):
+			return False
+
+		try:
+			obj = bus.get_object(service_name, obj_name)
+		except dbus.DBusException, e:
+			pretty.print_error(__name__, e)
+			return False
+		smanager = dbus.Interface(obj, iface_name)
+
+		app_id = version.PACKAGE_NAME
+		startup_id = os.getenv("DESKTOP_AUTOSTART_ID") or ""
+		self.client_id = smanager.RegisterClient(app_id, startup_id)
+		self._session_ended = False
+		self.output_debug("Connected to session as client",
+				self.client_id, startup_id)
+
+		private_iface_name = "org.gnome.SessionManager.ClientPrivate"
+		bus.add_signal_receiver(self._query_end_session, "QueryEndSession",
+				dbus_interface=private_iface_name)
+		bus.add_signal_receiver(self._end_session_signal, "EndSession",
+				dbus_interface=private_iface_name)
+		bus.add_signal_receiver(self._stop_signal, "Stop",
+				dbus_interface=private_iface_name)
+		return True
+
+	def _get_response_obj(self):
+		"""Return D-Bus session object for ClientPrivate Interface"""
+		service_name = "org.gnome.SessionManager"
+		obj_name = self.client_id
+		iface_name = "org.gnome.SessionManager.ClientPrivate"
+
+		try:
+			bus = dbus.Bus()
+			obj = bus.get_object(service_name, obj_name)
+		except dbus.DBusException, e:
+			pretty.print_error(__name__, e)
+			return None
+		smanager = dbus.Interface(obj, iface_name)
+		return smanager
+
+	def _query_end_session(self, flags):
+		self.output_debug("Query end", flags)
+
+		smanager = self._get_response_obj()
+		smanager and smanager.EndSessionResponse(True, "Always OK")
+
+	def _end_session_signal(self, flags):
+		self.output_debug("Session end", flags)
+		if not self._session_ended:
+			self._session_ended = True
+			self.emit("save-yourself")
+		smanager = self._get_response_obj()
+		smanager and smanager.EndSessionResponse(True, "Always OK")
+
+	def _stop_signal(self):
+		self.output_debug("Session stop")
+		self.emit("die")
 	def _session_save(self, obj, *args):
 		self.emit("save-yourself")
 	def _session_die(self, obj, *args):