Merge branch 'master' of git+ssh://dev.laptop.org/git/sugar

6 files changed, 346 insertions, 122 deletions

diff --git a/shell/PresenceService/Activity.py b/shell/PresenceService/Activity.py
index 5fbe8a5..f1e6f7c 100644
--- a/shell/PresenceService/Activity.py
+++ b/shell/PresenceService/Activity.py
@@ -1,5 +1,7 @@
 import dbus
 
+class NotFoundError(Exception):
+	pass
 
 class ActivityDBusHelper(dbus.service.Object):
 	def __init__(self, parent, bus_name, object_path):
@@ -8,22 +10,129 @@ class ActivityDBusHelper(dbus.service.Object):
 		self._object_path = object_path
 		dbus.service.Object.__init__(self, bus_name, self._object_path)
 
+	@dbus.service.method(BUDDY_DBUS_INTERFACE,
+						in_signature="s", out_signature="ao")
+	def getServicesOfType(self, stype):
+		services = self._parent.get_services_of_type(stype)
+		if not services:
+			raise NotFoundError("Not found")
+		ret = []
+		for serv in services:
+			ret.append(serv.object_path())
+		return ret
+
+	@dbus.service.method(BUDDY_DBUS_INTERFACE,
+						in_signature="", out_signature="ao")
+	def getServices(self):
+		services = self._parent.get_services()
+		if not services:
+			raise NotFoundError("Not found")
+		ret = []
+		for serv in services:
+			ret.append(serv.object_path())
+		return ret
+
+	@dbus.service.method(BUDDY_DBUS_INTERFACE,
+						in_signature="", out_signature="s")
+	def getId(self):
+		return self._parent.get_id()
+
+	@dbus.service.method(BUDDY_DBUS_INTERFACE,
+						in_signature="", out_signature="ao")
+	def getJoinedBuddies(self):
+		buddies = self._parent.get_joined_buddies()
+		if not buddies:
+			raise NotFoundError("Not found")
+		ret = []
+		for buddy in buddies:
+			ret.append(buddy.object_path())
+		return ret
+	
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
+	def ServiceAppeared(self, object_path):
+		pass
+
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
+	def ServiceDisappeared(self, object_path):
+		pass
+
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
+	def BuddyJoined(self, object_path):
+		pass
+
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
+	def BuddyLeft(self, object_path):
+		pass
+
 
 class Activity(object):
 	def __init__(self, bus_name, object_id, activity_id):
+		if not activity_id:
+			raise ValueError("Service must have a valid Activity ID")
 		self._activity_id = activity_id
 
 		self._buddies = []
-		self._services = {}	# service type -> Service
+		self._services = {}	# service type -> list of Services
+		self._services[service.get_type()] = []
 
 		self._object_id = object_id
 		self._object_path = "/org/laptop/Presence/Activities/%d" % self._object_id
 		self._dbus_helper = ActivityDBusHelper(self, bus_name, self._object_path)
 
+	def object_path(self):
+		return dbus.ObjectPath(self._object_path)
+
 	def get_id(self):
 		return self._activity_id
 
-	def get_service_of_type(self, stype):
+	def get_services(self):
+		return self._services.values()
+
+	def get_services_of_type(self, stype):
 		if self._services.has_key(stype):
 			return self._services[stype]
 		return None
+
+	def get_joined_buddies(self):
+		buddies = []
+		for serv in self._services.values():
+			buddies.append(serv.get_owner())
+		return buddies
+
+	def add_service(self, service):
+		stype = service.get_type()
+		if not self._services.has_key(stype):
+			self._services[stype] = []
+
+		# Send out the BuddyJoined signal if this is the first
+		# service from the buddy that we've seen
+		buddies = self.get_joined_buddies()
+		serv_owner = service.get_owner()
+		if serv_owner and serv_owner not in buddies:
+			self._dbus_helper.BuddyJoined(serv_owner.object_path())
+			serv_owner.add_activity(self)
+
+		if not service in self._services[stype]:
+			self._services[stype].append(service)
+			self._dbus_helper.ServiceAppeared(service.object_path())
+
+	def remove_service(self, service):
+		stype = service.get_type()
+		if not self._services.has_key(stype):
+			return
+		self._services[stype].remove(service)
+		self._dbus_helper.ServiceDisappeared(service.object_path())
+		if len(self._services[stype]) == 0:
+			del self._services[stype]
+
+		# Send out the BuddyLeft signal if this is the last
+		# service from the buddy
+		buddies = self.get_joined_buddies()
+		serv_owner = service.get_owner()
+		if serv_owner and serv_owner not in buddies:
+			serv_owner.remove_activity(self)
+			self._dbus_helper.BuddyLeft(serv_owner.object_path())
diff --git a/shell/PresenceService/Buddy.py b/shell/PresenceService/Buddy.py
index c3d17e1..ca2b566 100644
--- a/shell/PresenceService/Buddy.py
+++ b/shell/PresenceService/Buddy.py
@@ -3,10 +3,8 @@ import logging
 
 import gtk
 import gobject
+import dbus, dbus.service
 
-from sugar.p2p import Stream
-from sugar.p2p import network
-from sugar.presence import Service
 
 PRESENCE_SERVICE_TYPE = "_presence_olpc._tcp"
 BUDDY_DBUS_INTERFACE = "org.laptop.Presence.Buddy"
@@ -21,23 +19,28 @@ class BuddyDBusHelper(dbus.service.Object):
 		self._object_path = object_path
 		dbus.service.Object.__init__(self, bus_name, self._object_path)
 
-	@dbus.service.signal(BUDDY_DBUS_INTERFACE)
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
 	def ServiceAppeared(self, object_path):
 		pass
 
-	@dbus.service.signal(BUDDY_DBUS_INTERFACE)
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
 	def ServiceDisappeared(self, object_path):
 		pass
 
-	@dbus.service.signal(BUDDY_DBUS_INTERFACE)
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="")
 	def IconChanged(self):
 		pass
 
-	@dbus.service.signal(BUDDY_DBUS_INTERFACE)
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
 	def JoinedActivity(self, object_path):
 		pass
 
-	@dbus.service.signal(BUDDY_DBUS_INTERFACE)
+	@dbus.service.signal(BUDDY_DBUS_INTERFACE,
+						signature="o")
 	def LeftActivity(self, object_path):
 		pass
 
@@ -77,7 +80,7 @@ class Buddy(object):
 	"""Represents another person on the network and keeps track of the
 	activities and resources they make available for sharing."""
 
-	def __init__(self, bus_name, object_id, service):
+	def __init__(self, bus_name, object_id, service, owner=False):
 		if not bus_name:
 			raise ValueError("DBus bus name must be valid")
 		if not object_id or type(object_id) != type(1):
@@ -91,18 +94,20 @@ class Buddy(object):
 		self._valid = False
 		self._icon = None
 		self._icon_tries = 0
-		self._owner = False
-		self.add_service(service)
+		self._owner = owner
 
 		self._object_id = object_id
 		self._object_path = "/org/laptop/Presence/Buddies/%d" % self._object_id
 		self._dbus_helper = BuddyDBusHelper(self, bus_name, self._object_path)
 
+		self.add_service(service)
+
 	def object_path(self):
-		return self._object_path
+		return dbus.ObjectPath(self._object_path)
 
 	def _request_buddy_icon_cb(self, result_status, response, user_data):
 		"""Callback when icon request has completed."""
+		from sugar.p2p import network
 		icon = response
 		service = user_data
 		if result_status == network.RESULT_SUCCESS:
@@ -120,6 +125,7 @@ class Buddy(object):
 
 	def _request_buddy_icon(self, service):
 		"""Contact the buddy to retrieve the buddy icon."""
+		from sugar.p2p import Stream
 		buddy_stream = Stream.Stream.new_from_service(service, start_reader=False)
 		writer = buddy_stream.new_writer(service)
 		success = writer.custom_request("get_buddy_icon", self._request_buddy_icon_cb, service)
@@ -141,21 +147,7 @@ class Buddy(object):
 		if stype in self._services.keys():
 			return False
 		self._services[stype] = service
-		if self._valid:
-			self._dbus_helper.ServiceAppeared(dbus.ObjectPath(service.object_path()))
-
-		# If this is the first service we've seen that's owned  by
-		# a particular activity, send out the 'joined-activity' signal
-		actid = service.get_activity_id()
-		if actid is not None:
-			found = False
-			for serv in self._services.values():
-				if serv.get_activity_id() == actid and serv.get_type() != stype:
-					found = True
-					break
-			if not found:
-				print "Buddy (%s) joined activity %s." % (self._nick_name, actid)
-				self._dbus_helper.JoinedActivity(dbus.ObjectPath(activity.object_path()))
+		service.set_owner(self)
 
 		if stype == PRESENCE_SERVICE_TYPE:
 			# A buddy isn't valid until its official presence
@@ -163,8 +155,26 @@ class Buddy(object):
 			self._valid = True
 			print 'Requesting buddy icon %s' % self._nick_name
 			self._request_buddy_icon(service)
+
+		if self._valid:
+			self._dbus_helper.ServiceAppeared(service.object_path())
 		return True
 
+	def add_activity(self, activity):
+		actid = activity.get_id()
+		if activity in self._activities.values():
+			raise RuntimeError("Tried to add activity twice")
+		found = False
+		for serv in self._services.values():
+			if serv.get_activity_id() == activity.get_id():
+				found = True
+				break
+		if not found:
+			raise RuntimeError("Tried to add activity for which we had no service")
+		self._activities[actid] = activity
+		print "Buddy (%s) joined activity %s." % (self._nick_name, actid)
+		self._dbus_helper.JoinedActivity(activity.object_path())
+
 	def remove_service(self, service):
 		"""Remove a service from a buddy; ie, the activity was closed
 		or the buddy went away."""
@@ -175,25 +185,20 @@ class Buddy(object):
 		stype = service.get_type()
 		if self._services.has_key(stype):
 			if self._valid:
-				self._dbus_helper.ServiceDisappeared(dbus.ObjectPath(service.object_path()))
+				self._dbus_helper.ServiceDisappeared(service.object_path())
 			del self._services[stype]
 
-		# If this is the lase service owned  by a particular activity,
-		# and it's just been removed, send out the 'left-actvity' signal
-		actid = service.get_activity_id()
-		if actid is not None:
-			found = False
-			for serv in self._services.values():
-				if serv.get_activity_id() == actid:
-					found = True
-					break
-			if not found:
-				print "Buddy (%s) left activity %s." % (self._nick_name, actid)
-				self._dbus_helper.LeftActivity(dbus.ObjectPath(activity.object_path()))
-
 		if stype == PRESENCE_SERVICE_TYPE:
 			self._valid = False
 
+	def remove_activity(self, activity):
+		actid = activity.get_id()
+		if not self._activities.has_key(actid):
+			return
+		del self._activities[actid]
+		print "Buddy (%s) left activity %s." % (self._nick_name, actid)
+		self._dbus_helper.LeftActivity(activity.object_path())
+
 	def get_service_of_type(self, stype=None, activity=None):
 		"""Return a service of a certain type, or None if the buddy
 		doesn't provide that service."""
@@ -248,6 +253,5 @@ class Buddy(object):
 class Owner(Buddy):
 	"""Class representing the owner of the machine.  This is the client
 	portion of the Owner, paired with the server portion in Owner.py."""
-	def __init__(self, service):
-		Buddy.__init__(self, service)
-		self._owner = True
+	def __init__(self, bus_name, object_id, service):
+		Buddy.__init__(self, bus_name, object_id, service, owner=True)
diff --git a/shell/PresenceService/PresenceService.py b/shell/PresenceService/PresenceService.py
index cd5bd7f..657bb92 100644
--- a/shell/PresenceService/PresenceService.py
+++ b/shell/PresenceService/PresenceService.py
@@ -64,13 +64,54 @@ class ServiceAdv(object):
 		self._resolved = resolved
 
 
-_PRESENCE_INTERFACE = "org.laptop.Presence"
-
-class PresenceService(dbus.service.Object):
+_PRESENCE_SERVICE = "org.laptop.Presence"
+_PRESENCE_DBUS_INTERFACE = "org.laptop.Presence"
+_PRESENCE_OBJECT_PATH = "/org/laptop/Presence"
+
+class PresenceServiceDBusHelper(dbus.service.Object):
+	def __init__(self, parent, bus_name):
+		self._parent = parent
+		self._bus_name = bus_name
+		dbus.service.Object.__init__(self, bus_name, _PRESENCE_OBJECT_PATH)
+
+	@dbus.service.signal(_PRESENCE_DBUS_INTERFACE,
+						signature="o")
+	def BuddyAppeared(self, object_path):
+		pass
+
+	@dbus.service.signal(_PRESENCE_DBUS_INTERFACE,
+						signature="o")
+	def BuddyDisappeared(self, object_path):
+		pass
+
+	@dbus.service.signal(_PRESENCE_DBUS_INTERFACE,
+						signature="o")
+	def ServiceAppeared(self, object_path):
+		pass
+
+	@dbus.service.signal(_PRESENCE_DBUS_INTERFACE,
+						signature="o")
+	def ServiceDisappeared(self, object_path):
+		pass
+
+	@dbus.service.signal(_PRESENCE_DBUS_INTERFACE,
+						signature="o")
+	def ActivityAppeared(self, object_path):
+		pass
+
+	@dbus.service.signal(_PRESENCE_DBUS_INTERFACE,
+						signature="o")
+	def ActivityDisappeared(self, object_path):
+		pass
+
+
+class PresenceService(object):
 	def __init__(self):
 		# interface -> IP address: interfaces we've gotten events on so far
 		self._local_addrs = {}
 
+		self._next_object_id = 0
+
 		# Our owner object
 		self._owner = None
 
@@ -86,19 +127,19 @@ class PresenceService(dbus.service.Object):
 		# Resolved service list
 		self._service_advs = []
 
+		# Service types we care about resolving
+		self._registered_service_types = []
+
 		# Set up the dbus service we provide
 		session_bus = dbus.SessionBus()
-		bus_name = dbus.service.BusName('org.laptop.Presence', bus=session_bus)		
-		dbus.service.Object.__init__(self, bus_name, '/org/laptop/Presence')
+		self._bus_name = dbus.service.BusName(_PRESENCE_SERVICE, bus=session_bus)		
+		self._dbus_helper = PresenceServiceDBusHelper(self, self._bus_name)
 
 		# Connect to Avahi for mDNS stuff
 		self._system_bus = dbus.SystemBus()
-		self._mdns_service = dbus.Interface(self._bus.get_object(avahi.DBUS_NAME,
+		self._mdns_service = dbus.Interface(self._system_bus.get_object(avahi.DBUS_NAME,
 				avahi.DBUS_PATH_SERVER), avahi.DBUS_INTERFACE_SERVER)
-		# Start browsing the local mDNS domain
-		self._start()
 
-	def _start(self):
 		# Always browse .local
 		self._new_domain_cb(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, "local")
 
@@ -108,6 +149,11 @@ class PresenceService(dbus.service.Object):
 		db = dbus.Interface(self._system_bus.get_object(avahi.DBUS_NAME, domain_browser), avahi.DBUS_INTERFACE_DOMAIN_BROWSER)
 		db.connect_to_signal('ItemNew', self._new_domain_cb_glue)
 
+	def _get_next_object_id(self):
+		"""Increment and return the object ID counter."""
+		self._next_object_id = self._next_object_id + 1
+		return self._next_object_id
+
 	def _find_service_adv(self, interface=None, protocol=None, name=None, stype=None, domain=None):
 		"""Search a list of service advertisements for ones matching certain criteria."""
 		adv_list = []
@@ -125,6 +171,110 @@ class PresenceService(dbus.service.Object):
 			adv_list.append(adv)
 		return adv_list
 
+	def _handle_new_service_for_buddy(self, service):
+		"""Deal with a new discovered service object."""
+		# Once a service is resolved, we match it up to an existing buddy,
+		# or create a new Buddy if this is the first service known about the buddy
+		buddy_was_valid = False
+		name = service.get_name()
+		buddy = None
+		try:
+			buddy = self._buddies[name]
+			buddy_was_valid = buddy.is_valid()
+			service_added = buddy.add_service(service)
+			if service_added:
+				self._dbus_helper.ServiceAppeared(service.object_path())
+		except KeyError:
+			# Should this service mark the owner?
+			owner_nick = env.get_nick_name()
+			publisher_addr = service.get_publisher_address()
+			objid = self._get_next_object_id()
+			if name == owner_nick and publisher_addr in self._local_addrs.values():
+				buddy = Buddy.Owner(self._bus_name, objid, service)
+				self._owner = buddy
+				logging.debug("Owner is '%s'." % name)
+			else:
+				buddy = Buddy.Buddy(self._bus_name, objid, service)
+			self._buddies[name] = buddy
+			self._dbus_helper.ServiceAppeared(service.object_path())
+		if not buddy_was_valid and buddy.is_valid():
+			self._dbus_helper.BuddyAppeared(buddy.object_path())
+		return buddy
+
+	def _handle_new_activity_service(self, service):
+		# If the serivce is an activity service, merge it into our activities list
+		actid = service.get_activity_id()
+		if not actid:
+			return
+		activity = None
+		if not self._activities.has_key(actid):
+			objid = self._get_next_object_id()
+			activity = Activity.Activity(self._bus_name, objid, service)
+			self._activities[actid] = activity
+			self._dbus_helper.ActivityAppeared(activity.object_path())
+		else:
+			activity = self._activities[actid]
+
+		if activity:
+			activity.add_service(service)
+
+	def _handle_remove_activity_service(self, service):
+		actid = service.get_activity_id()
+		if not actid:
+			return
+		if not self._activities.has_key(actid):
+			return
+		activity = self._activities[actid]
+		activity.remove_service(service)
+		if len(activity.get_services()) == 0:
+			# Kill the activity
+			self._dbus_helper.ActivityDisappeared(activity.object_path())
+			del self._activities[actid]
+
+	def _resolve_service_reply_cb(self, interface, protocol, full_name, stype, domain, host, aprotocol, address, port, txt, flags):
+		"""When the service discovery finally gets here, we've got enough information about the
+		service to assign it to a buddy."""
+		logging.debug("resolved service '%s' type '%s' domain '%s' to %s:%s" % (full_name, stype, domain, address, port))
+
+		# If this service was previously unresolved, remove it from the
+		# unresolved list
+		adv_list = self._find_service_adv(interface=interface, protocol=protocol,
+				name=full_name, stype=stype, domain=domain)
+		if not adv_list:
+			return False
+		adv = adv_list[0]
+		adv.set_resolved(True)
+		if adv in self._resolve_queue:
+			self._resolve_queue.remove(adv)
+
+		# Update the service now that it's been resolved
+		objid = self._get_next_object_id()
+		service = Service.Service(self._bus_name, objid, name=full_name,
+				stype=stype, domain=domain, address=address, port=port,
+				properties=txt)
+		adv.set_service(service)
+
+		# Merge the service into our buddy and activity lists, if needed
+		buddy = self._handle_new_service_for_buddy(service)
+		if buddy and service.get_activity_id():
+			self._handle_new_activity_service(service)
+
+		return False
+
+	def _resolve_service_reply_cb_glue(self, interface, protocol, name, stype, domain, host, aprotocol, address, port, txt, flags):
+		gobject.idle_add(self._resolve_service_reply_cb, interface, protocol,
+				name, stype, domain, host, aprotocol, address, port, txt, flags)
+
+	def _resolve_service(self, adv):
+		"""Resolve and lookup a ZeroConf service to obtain its address and TXT records."""
+		# Ask avahi to resolve this particular service
+		logging.debug('resolving service %s %s' % (adv.name(), adv.stype()))
+		self._mdns_service.ResolveService(int(adv.interface()), int(adv.protocol()), adv.name(),
+				adv.stype(), adv.domain(), avahi.PROTO_UNSPEC, dbus.UInt32(0),
+				reply_handler=self._resolve_service_reply_cb_glue,
+				error_handler=self._resolve_service_error_handler)
+		return False
+
 	def _service_appeared_cb(self, interface, protocol, full_name, stype, domain, flags):
 		logging.debug("found service '%s' (%d) of type '%s' in domain '%s' on %i.%i." % (full_name, flags, stype, domain, interface, protocol))
 
@@ -141,7 +291,7 @@ class PresenceService(dbus.service.Object):
 
 		# Find out the IP address of this interface, if we haven't already
 		if interface not in self._local_addrs.keys():
-			ifname = self._server.GetNetworkInterfaceNameByIndex(interface)
+			ifname = self._mdns_service.GetNetworkInterfaceNameByIndex(interface)
 			if ifname:
 				addr = _get_local_ip_address(ifname)
 				if addr:
@@ -150,14 +300,9 @@ class PresenceService(dbus.service.Object):
 		# Decompose service name if we can
 		(actid, buddy_name) = Service._decompose_service_name(full_name)
 
-		# FIXME: find a better way of letting the StartPage get everything
-		self.emit('new-service-adv', actid, stype)
-
 		# If we care about the service right now, resolve it
 		resolve = False
-		if actid is not None or stype in self._allowed_service_types:
-			resolve = True
-		if self._is_special_service_type(stype):
+		if actid is not None or stype in self._registered_service_types:
 			resolve = True
 		if resolve and not adv in self._resolve_queue:
 			self._resolve_queue.append(adv)
@@ -197,11 +342,11 @@ class PresenceService(dbus.service.Object):
 			pass
 		else:
 			buddy.remove_service(service)
-			self.emit('service-disappeared', buddy, service)
+			self._dbus_helper.ServiceDisappeared(service.object_path())
+			self._handle_remove_activity_service(service)
 			if not buddy.is_valid():
-				self.emit("buddy-disappeared", buddy)
+				self._dbus_helper.BuddyDisappeared(buddy.object_path())
 				del self._buddies[buddy_name]
-			self._handle_remove_service_for_activity(service, buddy)
 
 		return False
 
@@ -257,3 +402,13 @@ class PresenceService(dbus.service.Object):
 
 	def _new_domain_cb_glue(self, interface, protocol, domain, flags=0):
 		gobject.idle_add(self._new_domain_cb, interface, protocol, domain, flags)
+
+
+
+def main():
+	import gtk
+	ps = PresenceService()
+	gtk.main()
+
+if __name__ == "__main__":
+	main()
diff --git a/shell/PresenceService/Service.py b/shell/PresenceService/Service.py
index 6475567..2e51c07 100644
--- a/shell/PresenceService/Service.py
+++ b/shell/PresenceService/Service.py
@@ -63,44 +63,6 @@ def is_multicast_address(address):
 		return True
 	return False
 
-def deserialize(sdict):
-	try:
-		name = sdict['name']
-		if type(name) != type(u""):
-			raise ValueError("name must be unicode.")
-		stype = sdict['stype']
-		if type(stype) != type(u""):
-			raise ValueError("type must be unicode.")
-		domain = sdict['domain']
-		if type(domain) != type(u""):
-			raise ValueError("domain must be unicode.")
-		port = sdict['port']
-		properties = sdict['properties']
-	except KeyError, exc:
-		raise ValueError("Serialized service object was not valid.")
-
-	address = None
-	try:
-		address = sdict['address']
-		if type(address) != type(u""):
-			raise ValueError("address must be unicode.")
-	except KeyError:
-		pass
-	
-	activity_id = None
-	try:
-		activity_id = sdict['activity_id']
-		if type(activity_id) != type(u""):
-			raise ValueError("activity id must be unicode.")
-	except KeyError:
-		pass
-
-	if activity_id is not None:
-		name = compose_service_name(name, activity_id)
-
-	return Service(name, stype, domain, address=address,
-		port=port, properties=properties)
-
 
 _ACTIVITY_ID_TAG = "ActivityID"
 SERVICE_DBUS_INTERFACE = "org.laptop.Presence.Service"
@@ -197,29 +159,23 @@ class Service(object):
 		if actid and not self._properties.has_key(_ACTIVITY_ID_TAG):
 			self._properties[_ACTIVITY_ID_TAG] = actid
 
+		self._owner = None
+
 		# register ourselves with dbus
 		self._object_id = object_id
 		self._object_path = "/org/laptop/Presence/Services/%d" % self._object_id
 		self._dbus_helper = ServiceDBusHelper(self, bus_name, self._object_path)
 
 	def object_path(self):
-		return self._object_path
+		return dbus.ObjectPath(self._object_path)
 
-	def serialize(self, owner=None):
-		sdict = {}
-		if owner is not None:
-			sdict['name'] = dbus.Variant(owner.get_nick_name())
-		else:
-			sdict['name'] = dbus.Variant(self._name)
-		sdict['stype'] = dbus.Variant(self._stype)
-		if self._activity_id:
-			sdict['activity_id'] = dbus.Variant(self._activity_id)
-		sdict['domain'] = dbus.Variant(self._domain)
-		if self._address:
-			sdict['address'] = dbus.Variant(self._address)
-		sdict['port'] = dbus.Variant(self._port)
-		sdict['properties'] = dbus.Variant(self._properties)
-		return sdict
+	def get_owner(self):
+		return self._owner
+
+	def set_owner(self, owner):
+		if self._owner is not None:
+			raise RuntimeError("Can only set a service's owner once")
+		self._owner = owner
 
 	def get_name(self):
 		"""Return the service's name, usually that of the
@@ -256,9 +212,7 @@ class Service(object):
 		elif type(properties) == type({}):
 			props = properties
 
-		# Set key/value pairs on internal property list, 
-		# also convert everything to local encoding (for now)
-		# to ensure consistency
+		# Set key/value pairs on internal property list
 		for key, value in props.items():
 			tmp_key = key
 			tmp_val = value
diff --git a/shell/PresenceService/__init__.py b/shell/PresenceService/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/shell/PresenceService/__init__.py
diff --git a/shell/Shell.py b/shell/Shell.py
index b0e04d6..416e655 100755
--- a/shell/Shell.py
+++ b/shell/Shell.py
@@ -14,6 +14,7 @@ from sugar import env
 from sugar.activity import Activity
 from PeopleWindow import PeopleWindow
 from Owner import ShellOwner
+from PresenceService import PresenceService
 
 class ShellDbusService(dbus.service.Object):
 	def __init__(self, shell, bus_name):
@@ -46,6 +47,7 @@ class Shell:
 		bus_name = dbus.service.BusName('com.redhat.Sugar.Shell', bus=session_bus)
 		ShellDbusService(self, bus_name)
 
+		self._ps = PresenceService.PresenceService()
 		self._owner = ShellOwner()
 
 		self._registry = ActivityRegistry()