diff options
Diffstat (limited to 'services/presence/PresenceService.py')
| -rw-r--r-- | services/presence/PresenceService.py | 719 |
1 files changed, 719 insertions, 0 deletions
diff --git a/services/presence/PresenceService.py b/services/presence/PresenceService.py new file mode 100644 index 0000000..1534ae9 --- /dev/null +++ b/services/presence/PresenceService.py @@ -0,0 +1,719 @@ +import avahi, dbus, dbus.glib, gobject +import Buddy +import Service +import Activity +import random +import logging +from sugar import util + + +_SA_UNRESOLVED = 0 +_SA_RESOLVE_PENDING = 1 +_SA_RESOLVED = 2 +class ServiceAdv(object): + """Wrapper class to track services from Avahi.""" + def __init__(self, interface, protocol, name, stype, domain, local): + self._interface = interface + self._protocol = protocol + if type(name) != type(u""): + raise ValueError("service advertisement name must be unicode.") + self._name = name + if type(stype) != type(u""): + raise ValueError("service advertisement type must be unicode.") + self._stype = stype + if type(domain) != type(u""): + raise ValueError("service advertisement domain must be unicode.") + self._domain = domain + self._service = None + if type(local) != type(False): + raise ValueError("local must be a boolean.") + self._local = local + self._state = _SA_UNRESOLVED + + def interface(self): + return self._interface + def protocol(self): + return self._protocol + def name(self): + return self._name + def stype(self): + return self._stype + def domain(self): + return self._domain + def is_local(self): + return self._local + def service(self): + return self._service + def set_service(self, service): + if not isinstance(service, Service.Service): + raise ValueError("must be a valid service.") + self._service = service + def state(self): + return self._state + def set_state(self, state): + if state == _SA_RESOLVE_PENDING: + if self._state == _SA_RESOLVED: + raise ValueError("Can't reset to resolve pending from resolved.") + self._state = state + + +_PRESENCE_SERVICE = "org.laptop.Presence" +_PRESENCE_DBUS_INTERFACE = "org.laptop.Presence" +_PRESENCE_OBJECT_PATH = "/org/laptop/Presence" + +class NotFoundError(Exception): + pass + +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 + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="", out_signature="ao") + def getServices(self): + services = self._parent.get_services() + ret = [] + for serv in services: + ret.append(serv.object_path()) + return ret + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="s", out_signature="ao") + def getServicesOfType(self, stype): + services = self._parent.get_services_of_type(stype) + ret = [] + for serv in services: + ret.append(serv.object_path()) + return ret + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="", out_signature="ao") + def getActivities(self): + activities = self._parent.get_activities() + ret = [] + for act in activities: + ret.append(act.object_path()) + return ret + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="s", out_signature="o") + def getActivity(self, actid): + act = self._parent.get_activity(actid) + if not act: + raise NotFoundError("Not found") + return act.object_path() + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="", out_signature="ao") + def getBuddies(self): + buddies = self._parent.get_buddies() + ret = [] + for buddy in buddies: + ret.append(buddy.object_path()) + return ret + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="s", out_signature="o") + def getBuddyByName(self, name): + buddy = self._parent.get_buddy_by_name(name) + if not buddy: + raise NotFoundError("Not found") + return buddy.object_path() + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="s", out_signature="o") + def getBuddyByAddress(self, addr): + buddy = self._parent.get_buddy_by_address(addr) + if not buddy: + raise NotFoundError("Not found") + return buddy.object_path() + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="", out_signature="o") + def getOwner(self): + owner = self._parent.get_owner() + if not owner: + raise NotFoundError("Not found") + return owner.object_path() + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="os", out_signature="o") + def joinActivity(self, activity_op, stype): + found_activity = None + acts = self._parent.get_activities() + for act in acts: + if act.object_path() == activity_op: + found_activity = act + break + if not found_activity: + raise NotFoundError("The activity %s was not found." % activity_op) + return self._parent.join_activity(found_activity, stype) + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="ssa{ss}sis", out_signature="o") + def shareActivity(self, activity_id, stype, properties, address, port, domain): + if not len(address): + address = None + service = self._parent.share_activity(activity_id, stype, properties, address, + port, domain) + return service.object_path() + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="ssa{ss}sis", out_signature="o") + def registerService(self, name, stype, properties, address, port, domain): + if not len(address): + address = None + service = self._parent.register_service(name, stype, properties, address, + port, domain) + return service.object_path() + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="o", out_signature="") + def unregisterService(self, service_op): + found_serv = None + services = self._parent.get_services() + for serv in services: + if serv.object_path() == service_op: + found_serv = serv + break + if not found_serv: + raise NotFoundError("The activity %s was not found." % service_op) + return self._parent.unregister_service(found_serv) + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="s", out_signature="") + def registerServiceType(self, stype): + self._parent.register_service_type(stype) + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE, + in_signature="s", out_signature="") + def unregisterServiceType(self, stype): + self._parent.unregister_service_type(stype) + + @dbus.service.method(_PRESENCE_DBUS_INTERFACE) + def start(self): + self._parent.start() + +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 + + self._buddies = {} # nick -> Buddy + self._services = {} # (name, type) -> Service + self._activities = {} # activity id -> Activity + + # Keep track of stuff we're already browsing + self._service_type_browsers = {} + self._service_browsers = {} + + # Resolved service list + self._service_advs = [] + + # Service types we care about resolving + self._registered_service_types = [] + + # Set up the dbus service we provide + self._session_bus = dbus.SessionBus() + self._bus_name = dbus.service.BusName(_PRESENCE_SERVICE, bus=self._session_bus) + self._dbus_helper = PresenceServiceDBusHelper(self, self._bus_name) + + # Our owner object + objid = self._get_next_object_id() + self._owner = Buddy.Owner(self, self._bus_name, objid) + self._buddies[self._owner.get_name()] = self._owner + + self._started = False + + def start(self): + if self._started: + return + self._started = True + + # Connect to Avahi for mDNS stuff + self._system_bus = dbus.SystemBus() + self._mdns_service = dbus.Interface(self._system_bus.get_object(avahi.DBUS_NAME, + avahi.DBUS_PATH_SERVER), avahi.DBUS_INTERFACE_SERVER) + + # Always browse .local + self._new_domain_cb(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, "local") + + # Connect to Avahi and start looking for stuff + domain_browser = self._mdns_service.DomainBrowserNew(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, + "", avahi.DOMAIN_BROWSER_BROWSE, dbus.UInt32(0)) + 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 get_services(self): + return self._services.values() + + def get_services_of_type(self, stype): + ret = [] + for serv in self._services.values(): + if serv.get_type() == stype: + ret.append(serv) + return ret + + def get_activities(self): + # Only return valid activities + ret = [] + for act in self._activities.values(): + if act.is_valid(): + ret.append(act) + return ret + + def get_activity(self, actid): + if self._activities.has_key(actid): + act = self._activities[actid] + if act.is_valid(): + return act + return None + + def get_buddies(self): + buddies = [] + for buddy in self._buddies.values(): + if buddy.is_valid(): + buddies.append(buddy) + return buddies + + def get_buddy_by_name(self, name): + if self._buddies.has_key(name): + if self._buddies[name].is_valid(): + return self._buddies[name] + return None + + def get_buddy_by_address(self, address): + for buddy in self._buddies.values(): + if buddy.get_address() == address and buddy.is_valid(): + return buddy + return None + + def get_owner(self): + return self._owner + + def _find_service_adv(self, interface=None, protocol=None, name=None, + stype=None, domain=None, local=None): + """Search a list of service advertisements for ones matching + certain criteria.""" + adv_list = [] + for adv in self._service_advs: + if interface and adv.interface() != interface: + continue + if protocol and adv.protocol() != protocol: + continue + if name and adv.name() != name: + continue + if stype and adv.stype() != stype: + continue + if domain and adv.domain() != domain: + continue + if local is not None and adv.is_local() != local: + continue + adv_list.append(adv) + return adv_list + + def _handle_new_service_for_buddy(self, service, local): + """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: + source_addr = service.get_source_address() + objid = self._get_next_object_id() + 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 + was_valid = False + 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 + else: + activity = self._activities[actid] + was_valid = activity.is_valid() + + if activity: + activity.add_service(service) + + if not was_valid and activity.is_valid(): + self._dbus_helper.ActivityAppeared(activity.object_path()) + + 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, adv, 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 not adv in self._service_advs: + return False + if adv.state() != _SA_RESOLVED: + return False + + # See if we know about this service already + key = (full_name, stype) + if not self._services.has_key(key): + 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, source_address=address, local=adv.is_local()) + self._services[key] = service + else: + # Already tracking this service; likely we were the one that shared it + # in the first place, and therefore the source address would not have + # been set yet + service = self._services[key] + if not service.get_source_address(): + service.set_source_address(address) + if not service.get_address(): + service.set_address(address) + adv.set_service(service) + + # Merge the service into our buddy and activity lists, if needed + buddy = self._handle_new_service_for_buddy(service, adv.is_local()) + if buddy and service.get_activity_id(): + self._handle_new_activity_service(service) + + return False + + def _resolve_service_reply_cb_glue(self, adv, interface, protocol, name, + stype, domain, host, aprotocol, address, port, txt, flags): + adv.set_state(_SA_RESOLVED) + gobject.idle_add(self._resolve_service_reply_cb, adv, interface, + protocol, name, stype, domain, host, aprotocol, address, + port, txt, flags) + + def _resolve_service_error_handler(self, adv, err): + adv.set_state(_SA_UNRESOLVED) + logging.error("Error resolving service %s.%s: %s" % (adv.name(), adv.stype(), err)) + + 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 + self._mdns_service.ResolveService(int(adv.interface()), int(adv.protocol()), adv.name(), + adv.stype(), adv.domain(), avahi.PROTO_UNSPEC, dbus.UInt32(0), + reply_handler=lambda *args: self._resolve_service_reply_cb_glue(adv, *args), + error_handler=lambda *args: self._resolve_service_error_handler(adv, *args)) + return False + + def _service_appeared_cb(self, interface, protocol, full_name, stype, domain, flags): + local = flags & avahi.LOOKUP_RESULT_OUR_OWN > 0 + adv_list = self._find_service_adv(interface=interface, protocol=protocol, + name=full_name, stype=stype, domain=domain, local=local) + adv = None + if not adv_list: + adv = ServiceAdv(interface=interface, protocol=protocol, name=full_name, + stype=stype, domain=domain, local=local) + self._service_advs.append(adv) + else: + adv = adv_list[0] + + # Decompose service name if we can + (actid, buddy_name) = Service.decompose_service_name(full_name) + + # If we care about the service right now, resolve it + resolve = False + if actid is not None or stype in self._registered_service_types: + resolve = True + if resolve and adv.state() == _SA_UNRESOLVED: + logging.debug("Found '%s' (%d) of type '%s' in domain" \ + " '%s' on %i.%i; will resolve." % (full_name, flags, stype, + domain, interface, protocol)) + adv.set_state(_SA_RESOLVE_PENDING) + gobject.idle_add(self._resolve_service, adv) + + return False + + def _service_appeared_cb_glue(self, interface, protocol, name, stype, domain, flags): + gobject.idle_add(self._service_appeared_cb, interface, protocol, name, stype, domain, flags) + + def _service_disappeared_cb(self, interface, protocol, full_name, stype, domain, flags): + local = flags & avahi.LOOKUP_RESULT_OUR_OWN > 0 + # If it's an unresolved service, remove it from our unresolved list + adv_list = self._find_service_adv(interface=interface, protocol=protocol, + name=full_name, stype=stype, domain=domain, local=local) + if not adv_list: + return False + + # Get the service object; if none, we have nothing left to do + adv = adv_list[0] + service = adv.service() + self._service_advs.remove(adv) + del adv + if not service: + return False + + logging.debug("Service %s.%s in domain %s on %i.%i disappeared." % (full_name, + stype, domain, interface, protocol)) + + self._dbus_helper.ServiceDisappeared(service.object_path()) + self._handle_remove_activity_service(service) + + # Decompose service name if we can + (actid, buddy_name) = Service.decompose_service_name(full_name) + + # Remove the service from the buddy + try: + buddy = self._buddies[buddy_name] + except KeyError: + pass + else: + buddy.remove_service(service) + if not buddy.is_valid(): + self._dbus_helper.BuddyDisappeared(buddy.object_path()) + del self._buddies[buddy_name] + key = (service.get_full_name(), service.get_type()) + del self._services[key] + return False + + def _service_disappeared_cb_glue(self, interface, protocol, name, stype, domain, flags): + gobject.idle_add(self._service_disappeared_cb, interface, protocol, name, stype, domain, flags) + + def _new_service_type_cb(self, interface, protocol, stype, domain, flags): + # Are we already browsing this domain for this type? + if self._service_browsers.has_key((interface, protocol, stype, domain)): + return + + # Start browsing for all services of this type in this domain + s_browser = self._mdns_service.ServiceBrowserNew(interface, protocol, stype, domain, dbus.UInt32(0)) + browser_obj = dbus.Interface(self._system_bus.get_object(avahi.DBUS_NAME, s_browser), + avahi.DBUS_INTERFACE_SERVICE_BROWSER) + browser_obj.connect_to_signal('ItemNew', self._service_appeared_cb_glue) + browser_obj.connect_to_signal('ItemRemove', self._service_disappeared_cb_glue) + + self._service_browsers[(interface, protocol, stype, domain)] = browser_obj + return False + + def _new_service_type_cb_glue(self, interface, protocol, stype, domain, flags): + gobject.idle_add(self._new_service_type_cb, interface, protocol, stype, domain, flags) + + def _new_domain_cb(self, interface, protocol, domain, flags=0): + """Callback from Avahi when a new domain has been found. Start + browsing the new domain.""" + # Only use .local for now... + if domain != "local": + return + + # Are we already browsing this domain? + if self._service_type_browsers.has_key((interface, protocol, domain)): + return + + # Start browsing this domain for the services its members offer + try: + st_browser = self._mdns_service.ServiceTypeBrowserNew(interface, protocol, domain, dbus.UInt32(0)) + browser_obj = dbus.Interface(self._system_bus.get_object(avahi.DBUS_NAME, st_browser), + avahi.DBUS_INTERFACE_SERVICE_TYPE_BROWSER) + except dbus.DBusException, exc: + str_exc = str(exc) + logging.error("got exception %s while attempting to browse domain %s on %i.%i" % (str_exc, domain, interface, protocol)) + if str_exc.find("The name org.freedesktop.Avahi was not provided by any .service files") >= 0: + raise Exception("Avahi does not appear to be running. '%s'" % str_exc) + else: + raise exc + logging.debug("Browsing domain '%s' on %i.%i ..." % (domain, interface, protocol)) + browser_obj.connect_to_signal('ItemNew', self._new_service_type_cb_glue) + self._service_type_browsers[(interface, protocol, domain)] = browser_obj + return False + + def _new_domain_cb_glue(self, interface, protocol, domain, flags=0): + gobject.idle_add(self._new_domain_cb, interface, protocol, domain, flags) + + def join_activity(self, activity, stype): + services = activity.get_services_of_type(stype) + if not len(services): + raise NotFoundError("The service type %s was not present within the activity %s" % (stype, activity.object_path())) + act_service = services[0] + props = act_service.get_properties() + color = activity.get_color() + if color: + props['color'] = color + return self._share_activity(activity.get_id(), stype, properties, + act_service.get_address(), act_service.get_port(), act_service.get_domain()) + + def share_activity(self, activity_id, stype, properties=None, address=None, port=-1, domain=u"local"): + """Convenience function to share an activity with other buddies.""" + if not util.validate_activity_id(activity_id): + raise ValueError("invalid activity id") + owner_nick = self._owner.get_name() + real_name = Service.compose_service_name(owner_nick, activity_id) + if address and type(address) != type(u""): + raise ValueError("address must be a unicode string.") + if address == None and stype.endswith('_udp'): + # Use random currently unassigned multicast address + address = u"232.%d.%d.%d" % (random.randint(0, 254), random.randint(1, 254), + random.randint(1, 254)) + properties['address'] = address + properties['port'] = port + if port and port != -1 and (type(port) != type(1) or port <= 1024 or port >= 65535): + raise ValueError("port must be a number between 1024 and 65535") + + color = self._owner.get_color() + if color: + properties['color'] = color + + logging.debug('Share activity %s, type %s, address %s, port %d, properties %s' % (activity_id, stype, address, port, properties)) + return self.register_service(real_name, stype, properties, address, port, domain) + + def register_service(self, name, stype, properties={}, address=None, port=-1, domain=u"local"): + """Register a new service, advertising it to other Buddies on the network.""" + (actid, person_name) = Service.decompose_service_name(name) + if self.get_owner() and person_name != self.get_owner().get_name(): + raise RuntimeError("Tried to register a service that didn't have Owner nick as the service name!") + if not domain or not len(domain): + domain = u"local" + if not port or port == -1: + port = random.randint(4000, 65000) + + try: + obj = self._system_bus.get_object(avahi.DBUS_NAME, self._mdns_service.EntryGroupNew()) + group = dbus.Interface(obj, avahi.DBUS_INTERFACE_ENTRY_GROUP) + + # Add properties; ensure they are converted to ByteArray types + # because python sometimes can't figure that out + info = dbus.Array([], signature="aay") + for k, v in properties.items(): + info.append(dbus.types.ByteArray("%s=%s" % (k, v))) + + objid = self._get_next_object_id() + service = Service.Service(self._bus_name, objid, name=name, + stype=stype, domain=domain, address=address, port=port, + properties=properties, source_address=None, local=True) + self._services[(name, stype)] = service + port = service.get_port() + + logging.debug("PS: Will register service with name='%s', stype='%s'," \ + " domain='%s', address='%s', port=%d, info='%s'" % (name, stype, domain, address, port, info)) + group.AddService(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, 0, dbus.String(name), + dbus.String(stype), dbus.String(domain), dbus.String(""), # let Avahi figure the 'host' out + dbus.UInt16(port), info) + service.set_avahi_entry_group(group) + group.Commit() + except dbus.exceptions.DBusException, exc: + # FIXME: ignore local name collisions, since that means + # the zeroconf service is already registered. Ideally we + # should un-register it an re-register with the correct info + if str(exc) == "Local name collision": + pass + self.register_service_type(stype) + return service + + def unregister_service(self, service): + group = service.get_avahi_entry_group() + if not group: + raise ValueError("Service was not a local service provided by this laptop!") + group.Free() + + def register_service_type(self, stype): + """Requests that the Presence service look for and recognize + a certain mDNS service types.""" + if type(stype) != type(u""): + raise ValueError("service type must be a unicode string.") + if stype in self._registered_service_types: + return + self._registered_service_types.append(stype) + + # Find unresolved services that match the service type + # we're now interested in, and resolve them + resolv_list = [] + + # Find services of this type + resolv_list = self._find_service_adv(stype=stype) + # Request resolution for them if they aren't in-process already + for adv in resolv_list: + if adv.state() == _SA_UNRESOLVED: + adv.set_state(_SA_RESOLVE_PENDING) + gobject.idle_add(self._resolve_service, adv) + + def unregister_service_type(self, stype): + """Stop tracking a certain mDNS service.""" + if type(stype) != type(u""): + raise ValueError("service type must be a unicode string.") + if stype in self._registered_service_types: + self._registered_service_types.remove(stype) + + +def main(): + from sugar import TracebackUtils + loop = gobject.MainLoop() + ps = PresenceService() + tbh = TracebackUtils.TracebackHelper() + try: + loop.run() + except KeyboardInterrupt: + print 'Ctrl+C pressed, exiting...' + + del tbh + + +if __name__ == "__main__": + main() |