class Broker(object): """ Basic WAMP broker. """ log = make_logger() def __init__(self, router, options=None): """ :param router: The router this dealer is part of. :type router: Object that implements :class:`crossbar.router.interfaces.IRouter`. :param options: Router options. :type options: Instance of :class:`crossbar.router.types.RouterOptions`. """ self._router = router self._options = options or RouterOptions() # subscription map managed by this broker self._subscription_map = UriObservationMap() # map: session -> set of subscriptions (needed for detach) self._session_to_subscriptions = {} # check all topic URIs with strict rules self._option_uri_strict = self._options.uri_check == RouterOptions.URI_CHECK_STRICT # supported features from "WAMP Advanced Profile" self._role_features = role.RoleBrokerFeatures(publisher_identification=True, pattern_based_subscription=True, session_meta_api=True, subscription_meta_api=True, subscriber_blackwhite_listing=True, publisher_exclusion=True, subscription_revocation=True, event_retention=True, payload_transparency=True, payload_encryption_cryptobox=True) # store for event history if self._router._store: self._event_store = self._router._store.event_store else: self._event_store = None # if there is a store, let the store attach itself to all the subscriptions # it is configured to track if self._event_store: self._event_store.attach_subscription_map(self._subscription_map) def attach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.attach` """ if session not in self._session_to_subscriptions: self._session_to_subscriptions[session] = set() else: raise Exception(u"session with ID {} already attached".format(session._session_id)) def detach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.detach` """ if session in self._session_to_subscriptions: for subscription in self._session_to_subscriptions[session]: was_subscribed, was_last_subscriber = self._subscription_map.drop_observer(session, subscription) was_deleted = False # delete it if there are no subscribers and no retained events # if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: was_deleted = True self._subscription_map.delete_observation(subscription) # publish WAMP meta events # if self._router._realm: service_session = self._router._realm.session if service_session and not subscription.uri.startswith(u'wamp.'): if was_subscribed: service_session.publish(u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id) if was_deleted: service_session.publish(u'wamp.subscription.on_delete', session._session_id, subscription.id) del self._session_to_subscriptions[session] else: raise Exception("session with ID {} not attached".format(session._session_id)) def processPublish(self, session, publish): """ Implements :func:`crossbar.router.interfaces.IBroker.processPublish` """ # check topic URI: for PUBLISH, must be valid URI (either strict or loose), and # all URI components must be non-empty if self._option_uri_strict: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(publish.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(publish.topic) if not uri_is_valid: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [u"publish with invalid topic URI '{0}' (URI strict checking {1})".format(publish.topic, self._option_uri_strict)]) self._router.send(session, reply) return # disallow publication to topics starting with "wamp." and "crossbar." other than for # trusted sessions (that are sessions built into Crossbar.io) # if session._authrole is not None and session._authrole != u"trusted": is_restricted = publish.topic.startswith(u"wamp.") or publish.topic.startswith(u"crossbar.") if is_restricted: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [u"publish with restricted topic URI '{0}'".format(publish.topic)]) self._router.send(session, reply) return # get subscriptions active on the topic published to # subscriptions = self._subscription_map.match_observations(publish.topic) # check if the event is being persisted by checking if we ourself are among the observers # on _any_ matching subscription # we've been previously added to observer lists on subscriptions ultimately from # node configuration and during the broker starts up. store_event = False if self._event_store: for subscription in subscriptions: if self._event_store in subscription.observers: store_event = True break if store_event: self.log.debug('Persisting event on topic "{topic}"', topic=publish.topic) # check if the event is to be retained by inspecting the 'retain' flag retain_event = False if publish.retain: retain_event = True # go on if (otherwise there isn't anything to do anyway): # # - there are any active subscriptions OR # - the publish is to be acknowledged OR # - the event is to be persisted OR # - the event is to be retained # if subscriptions or publish.acknowledge or store_event or retain_event: # If it's a MQTT publish, we need to adjust the arguments. if getattr(publish, "_mqtt_publish", False): from crossbar.adapter.mqtt.wamp import mqtt_payload_transform tfd = mqtt_payload_transform(self._router._mqtt_payload_format, publish.payload) if not tfd: # If we have no message to give, drop it entirely return else: publish.payload = None publish.args, publish.kwargs = tfd # validate payload # if publish.payload is None: try: self._router.validate('event', publish.topic, publish.args, publish.kwargs) except Exception as e: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_ARGUMENT, [u"publish to topic URI '{0}' with invalid application payload: {1}".format(publish.topic, e)]) self._router.send(session, reply) return # authorize PUBLISH action # d = self._router.authorize(session, publish.topic, u'publish') def on_authorize_success(authorization): # the call to authorize the action _itself_ succeeded. now go on depending on whether # the action was actually authorized or not .. # if not authorization[u'allow']: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.NOT_AUTHORIZED, [u"session not authorized to publish to topic '{0}'".format(publish.topic)]) self._router.send(session, reply) else: # new ID for the publication # publication = util.id() # persist event (this is done only once, regardless of the number of subscriptions # the event matches on) # if store_event: self._event_store.store_event(session._session_id, publication, publish.topic, publish.args, publish.kwargs) # retain event on the topic # if retain_event: observation = self._subscription_map.get_observation(publish.topic) if not observation: # No observation, lets make a new one observation = self._subscription_map.create_observation(publish.topic, extra=SubscriptionExtra()) if observation.extra.retained_events: if not publish.eligible and not publish.exclude: observation.extra.retained_events = [publish] else: observation.extra.retained_events.append(publish) else: observation.extra.retained_events = [publish] # send publish acknowledge immediately when requested # if publish.acknowledge: reply = message.Published(publish.request, publication) self._router.send(session, reply) # publisher disclosure # if authorization[u'disclose']: disclose = True elif (publish.topic.startswith(u"wamp.") or publish.topic.startswith(u"crossbar.")): disclose = True else: disclose = False if disclose: publisher = session._session_id publisher_authid = session._authid publisher_authrole = session._authrole else: publisher = None publisher_authid = None publisher_authrole = None # skip publisher # if publish.exclude_me is None or publish.exclude_me: me_also = False else: me_also = True # iterate over all subscriptions .. # for subscription in subscriptions: # persist event history, but check if it is persisted on the individual subscription! # if store_event and self._event_store in subscription.observers: self._event_store.store_event_history(publication, subscription.id) # initial list of receivers are all subscribers on a subscription .. # receivers = subscription.observers # filter by "eligible" receivers # if publish.eligible: # map eligible session IDs to eligible sessions eligible = [] for session_id in publish.eligible: if session_id in self._router._session_id_to_session: eligible.append(self._router._session_id_to_session[session_id]) # filter receivers for eligible sessions receivers = set(eligible) & receivers # remove "excluded" receivers # if publish.exclude: # map excluded session IDs to excluded sessions exclude = [] for s in publish.exclude: if s in self._router._session_id_to_session: exclude.append(self._router._session_id_to_session[s]) # filter receivers for excluded sessions if exclude: receivers = receivers - set(exclude) # if receivers is non-empty, dispatch event .. # receivers_cnt = len(receivers) - (1 if self in receivers else 0) if receivers_cnt: # for pattern-based subscriptions, the EVENT must contain # the actual topic being published to # if subscription.match != message.Subscribe.MATCH_EXACT: topic = publish.topic else: topic = None if publish.payload: msg = message.Event(subscription.id, publication, payload=publish.payload, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic, enc_algo=publish.enc_algo, enc_key=publish.enc_key, enc_serializer=publish.enc_serializer) else: msg = message.Event(subscription.id, publication, args=publish.args, kwargs=publish.kwargs, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic) for receiver in receivers: if (me_also or receiver != session) and receiver != self._event_store: # the receiving subscriber session # might have no transport, or no # longer be joined if receiver._session_id and receiver._transport: self._router.send(receiver, msg) def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ self.log.failure("Authorization failed", failure=err) if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.AUTHORIZATION_FAILED, [u"failed to authorize session for publishing to topic URI '{0}': {1}".format(publish.topic, err.value)] ) self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processSubscribe(self, session, subscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processSubscribe` """ # check topic URI: for SUBSCRIBE, must be valid URI (either strict or loose), and all # URI components must be non-empty for normal subscriptions, may be empty for # wildcard subscriptions and must be non-empty for all but the last component for # prefix subscriptions # if self._option_uri_strict: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_STRICT_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_STRICT_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(subscribe.topic) else: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_LOOSE_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_LOOSE_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(subscribe.topic) if not uri_is_valid: reply = message.Error(message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.INVALID_URI, [u"subscribe for invalid topic URI '{0}'".format(subscribe.topic)]) self._router.send(session, reply) return # authorize SUBSCRIBE action # d = self._router.authorize(session, subscribe.topic, u'subscribe') def on_authorize_success(authorization): if not authorization[u'allow']: # error reply since session is not authorized to subscribe # replies = [message.Error(message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.NOT_AUTHORIZED, [u"session is not authorized to subscribe to topic '{0}'".format(subscribe.topic)])] else: # ok, session authorized to subscribe. now get the subscription # subscription, was_already_subscribed, is_first_subscriber = self._subscription_map.add_observer(session, subscribe.topic, subscribe.match, extra=SubscriptionExtra()) if not was_already_subscribed: self._session_to_subscriptions[session].add(subscription) # publish WAMP meta events # if self._router._realm: service_session = self._router._realm.session if service_session and not subscription.uri.startswith(u'wamp.'): if is_first_subscriber: subscription_details = { u'id': subscription.id, u'created': subscription.created, u'uri': subscription.uri, u'match': subscription.match, } service_session.publish(u'wamp.subscription.on_create', session._session_id, subscription_details) if not was_already_subscribed: service_session.publish(u'wamp.subscription.on_subscribe', session._session_id, subscription.id) # check for retained events # def _get_retained_event(): if subscription.extra.retained_events: retained_events = list(subscription.extra.retained_events) retained_events.reverse() for publish in retained_events: authorised = False if not publish.exclude and not publish.eligible: authorised = True elif session._session_id in publish.eligible and session._session_id not in publish.exclude: authorised = True if authorised: publication = util.id() if publish.payload: msg = message.Event(subscription.id, publication, payload=publish.payload, retained=True, enc_algo=publish.enc_algo, enc_key=publish.enc_key, enc_serializer=publish.enc_serializer) else: msg = message.Event(subscription.id, publication, args=publish.args, kwargs=publish.kwargs, retained=True) return [msg] return [] # acknowledge subscribe with subscription ID # replies = [message.Subscribed(subscribe.request, subscription.id)] if subscribe.get_retained: replies.extend(_get_retained_event()) # send out reply to subscribe requestor # [self._router.send(session, reply) for reply in replies] def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ # XXX same as another code-block, can we collapse? self.log.failure("Authorization failed", failure=err) reply = message.Error( message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.AUTHORIZATION_FAILED, [u"failed to authorize session for subscribing to topic URI '{0}': {1}".format(subscribe.topic, err.value)] ) self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processUnsubscribe(self, session, unsubscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processUnsubscribe` """ # get subscription by subscription ID or None (if it doesn't exist on this broker) # subscription = self._subscription_map.get_observation_by_id(unsubscribe.subscription) if subscription: if session in subscription.observers: was_subscribed, was_last_subscriber = self._unsubscribe(subscription, session) reply = message.Unsubscribed(unsubscribe.request) else: # subscription exists on this broker, but the session that wanted to unsubscribe wasn't subscribed # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) else: # subscription doesn't even exist on this broker # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) self._router.send(session, reply) def _unsubscribe(self, subscription, session): # drop session from subscription observers # was_subscribed, was_last_subscriber = self._subscription_map.drop_observer(session, subscription) was_deleted = False if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: was_deleted = True self._subscription_map.delete_observation(subscription) # remove subscription from session->subscriptions map # if was_subscribed: self._session_to_subscriptions[session].discard(subscription) # publish WAMP meta events # if self._router._realm: service_session = self._router._realm.session if service_session and not subscription.uri.startswith(u'wamp.'): if was_subscribed: service_session.publish(u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id) if was_deleted: service_session.publish(u'wamp.subscription.on_delete', session._session_id, subscription.id) return was_subscribed, was_last_subscriber def removeSubscriber(self, subscription, session, reason=None): """ Actively unsubscribe a subscriber session from a subscription. """ was_subscribed, was_last_subscriber = self._unsubscribe(subscription, session) if 'subscriber' in session._session_roles and session._session_roles['subscriber'] and session._session_roles['subscriber'].subscription_revocation: reply = message.Unsubscribed(0, subscription=subscription.id, reason=reason) self._router.send(session, reply) return was_subscribed, was_last_subscriber
class Broker(object): """ Basic WAMP broker. """ log = make_logger() def __init__(self, router, reactor, options=None): """ :param router: The router this broker is part of. :type router: Object that implements :class:`crossbar.router.interfaces.IRouter`. :param options: Router options. :type options: Instance of :class:`crossbar.router.types.RouterOptions`. """ self._router = router self._reactor = reactor self._options = options or RouterOptions() # generator for WAMP request IDs self._request_id_gen = util.IdGenerator() # subscription map managed by this broker self._subscription_map = UriObservationMap() # map: session -> set of subscriptions (needed for detach) self._session_to_subscriptions = {} # check all topic URIs with strict rules self._option_uri_strict = self._options.uri_check == RouterOptions.URI_CHECK_STRICT # supported features from "WAMP Advanced Profile" self._role_features = role.RoleBrokerFeatures(publisher_identification=True, pattern_based_subscription=True, session_meta_api=True, subscription_meta_api=True, subscriber_blackwhite_listing=True, publisher_exclusion=True, subscription_revocation=True, event_retention=True, payload_transparency=True, payload_encryption_cryptobox=True) # store for event history if self._router._store: self._event_store = self._router._store.event_store else: self._event_store = None # if there is a store, let the store attach itself to all the subscriptions # it is configured to track if self._event_store: self._event_store.attach_subscription_map(self._subscription_map) def attach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.attach` """ if session not in self._session_to_subscriptions: self._session_to_subscriptions[session] = set() else: raise Exception(u"session with ID {} already attached".format(session._session_id)) def detach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.detach` """ if session in self._session_to_subscriptions: for subscription in self._session_to_subscriptions[session]: was_subscribed, was_last_subscriber = self._subscription_map.drop_observer(session, subscription) was_deleted = False # delete it if there are no subscribers and no retained events # if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: was_deleted = True self._subscription_map.delete_observation(subscription) # publish WAMP meta events, if we have a service session, but # not for the meta API itself! # if self._router._realm and \ self._router._realm.session and \ not subscription.uri.startswith(u'wamp.'): def _publish(subscription): service_session = self._router._realm.session # FIXME: what about exclude_authid as colleced from forward_for? like we do elsewhere in this file! options = types.PublishOptions( correlation_id=None, correlation_is_anchor=True, correlation_is_last=False ) if was_subscribed: service_session.publish( u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id, options=options, ) if was_deleted: options.correlation_is_last = True service_session.publish( u'wamp.subscription.on_delete', session._session_id, subscription.id, options=options, ) # we postpone actual sending of meta events until we return to this client session self._reactor.callLater(0, _publish, subscription) del self._session_to_subscriptions[session] else: raise Exception("session with ID {} not attached".format(session._session_id)) def _filter_publish_receivers(self, receivers, publish): """ Internal helper. Does all filtering on a candidate set of Publish receivers, based on all the white/blacklist options in 'publish'. """ # filter by "eligible" receivers # if publish.eligible: # map eligible session IDs to eligible sessions eligible = set() for session_id in publish.eligible: if session_id in self._router._session_id_to_session: eligible.add(self._router._session_id_to_session[session_id]) # filter receivers for eligible sessions receivers = eligible & receivers # if "eligible_authid" we only accept receivers that have the correct authid if publish.eligible_authid: eligible = set() for aid in publish.eligible_authid: eligible.update(self._router._authid_to_sessions.get(aid, set())) receivers = receivers & eligible # if "eligible_authrole" we only accept receivers that have the correct authrole if publish.eligible_authrole: eligible = set() for ar in publish.eligible_authrole: eligible.update(self._router._authrole_to_sessions.get(ar, set())) receivers = receivers & eligible # remove "excluded" receivers # if publish.exclude: # map excluded session IDs to excluded sessions exclude = set() for s in publish.exclude: if s in self._router._session_id_to_session: exclude.add(self._router._session_id_to_session[s]) # filter receivers for excluded sessions if exclude: receivers = receivers - exclude # remove auth-id based receivers if publish.exclude_authid: for aid in publish.exclude_authid: receivers = receivers - self._router._authid_to_sessions.get(aid, set()) # remove authrole based receivers if publish.exclude_authrole: for ar in publish.exclude_authrole: receivers = receivers - self._router._authrole_to_sessions.get(ar, set()) return receivers def processPublish(self, session, publish): """ Implements :func:`crossbar.router.interfaces.IBroker.processPublish` """ if self._router.is_traced: if not publish.correlation_id: publish.correlation_id = self._router.new_correlation_id() publish.correlation_is_anchor = True if not publish.correlation_uri: publish.correlation_uri = publish.topic # check topic URI: for PUBLISH, must be valid URI (either strict or loose), and # all URI components must be non-empty if self._option_uri_strict: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(publish.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(publish.topic) if not uri_is_valid: if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False self._router._factory._worker._maybe_trace_rx_msg(session, publish) reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [u"publish with invalid topic URI '{0}' (URI strict checking {1})".format(publish.topic, self._option_uri_strict)]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) else: if self._router.is_traced: publish.correlation_is_last = True self._router._factory._worker._maybe_trace_rx_msg(session, publish) return # disallow publication to topics starting with "wamp." other than for # trusted sessions (that are sessions built into Crossbar.io routing core) # if session._authrole is not None and session._authrole != u"trusted": is_restricted = publish.topic.startswith(u"wamp.") if is_restricted: if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False self._router._factory._worker._maybe_trace_rx_msg(session, publish) reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [u"publish with restricted topic URI '{0}'".format(publish.topic)]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) else: if self._router.is_traced: publish.correlation_is_last = True self._router._factory._worker._maybe_trace_rx_msg(session, publish) return # get subscriptions active on the topic published to # subscriptions = self._subscription_map.match_observations(publish.topic) # check if the event is being persisted by checking if we ourself are among the observers # on _any_ matching subscription # we've been previously added to observer lists on subscriptions ultimately from # node configuration and during the broker starts up. store_event = False if self._event_store: for subscription in subscriptions: if self._event_store in subscription.observers: store_event = True break if store_event: self.log.debug('Persisting event on topic "{topic}"', topic=publish.topic) # check if the event is to be retained by inspecting the 'retain' flag retain_event = False if publish.retain: retain_event = True # go on if (otherwise there isn't anything to do anyway): # # - there are any active subscriptions OR # - the publish is to be acknowledged OR # - the event is to be persisted OR # - the event is to be retained # if not (subscriptions or publish.acknowledge or store_event or retain_event): # the received PUBLISH message is the only one received/sent # for this WAMP action, so mark it as "last" (there is another code path below!) if self._router.is_traced: if publish.correlation_is_last is None: publish.correlation_is_last = True self._router._factory._worker._maybe_trace_rx_msg(session, publish) else: # validate payload # if publish.payload is None: try: self._router.validate('event', publish.topic, publish.args, publish.kwargs) except Exception as e: if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False self._router._factory._worker._maybe_trace_rx_msg(session, publish) reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_ARGUMENT, [u"publish to topic URI '{0}' with invalid application payload: {1}".format(publish.topic, e)]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) else: if self._router.is_traced: publish.correlation_is_last = True self._router._factory._worker._maybe_trace_rx_msg(session, publish) return # authorize PUBLISH action # d = self._router.authorize(session, publish.topic, u'publish', options=publish.marshal_options()) def on_authorize_success(authorization): # the call to authorize the action _itself_ succeeded. now go on depending on whether # the action was actually authorized or not .. # if not authorization[u'allow']: if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False self._router._factory._worker._maybe_trace_rx_msg(session, publish) reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.NOT_AUTHORIZED, [u"session not authorized to publish to topic '{0}'".format(publish.topic)]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) else: if self._router.is_traced: publish.correlation_is_last = True self._router._factory._worker._maybe_trace_rx_msg(session, publish) else: # new ID for the publication # publication = util.id() # publisher disclosure # if authorization[u'disclose']: disclose = True elif (publish.topic.startswith(u"wamp.") or publish.topic.startswith(u"crossbar.")): disclose = True else: disclose = False forward_for = None if disclose: if publish.forward_for: publisher = publish.forward_for[0]['session'] publisher_authid = publish.forward_for[0]['authid'] publisher_authrole = publish.forward_for[0]['authrole'] forward_for = publish.forward_for + [ { 'session': session._session_id, 'authid': session._authid, 'authrole': session._authrole, } ] else: publisher = session._session_id publisher_authid = session._authid publisher_authrole = session._authrole else: publisher = None publisher_authid = None publisher_authrole = None # skip publisher # if publish.exclude_me is None or publish.exclude_me: me_also = False else: me_also = True # persist event (this is done only once, regardless of the number of subscriptions # the event matches on) # if store_event: self._event_store.store_event(session, publication, publish) # retain event on the topic # if retain_event: retained_event = RetainedEvent(publish, publisher, publisher_authid, publisher_authrole) observation = self._subscription_map.get_observation(publish.topic) if not observation: # No observation, lets make a new one observation = self._subscription_map.create_observation(publish.topic, extra=SubscriptionExtra()) else: # this can happen if event-history is # enabled on the topic: the event-store # creates an observation before any client # could possible hit the code above if observation.extra is None: observation.extra = SubscriptionExtra() elif not isinstance(observation.extra, SubscriptionExtra): raise Exception( "incorrect 'extra' for '{}'".format(publish.topic) ) if observation.extra.retained_events: if not publish.eligible and not publish.exclude: observation.extra.retained_events = [retained_event] else: observation.extra.retained_events.append(retained_event) else: observation.extra.retained_events = [retained_event] subscription_to_receivers = {} total_receivers_cnt = 0 # iterate over all subscriptions and determine actual receivers of the event # under the respective subscription. also persist events (independent of whether # there is any actual receiver right now on the subscription) # for subscription in subscriptions: # initial list of receivers are all subscribers on a subscription .. # receivers = subscription.observers receivers = self._filter_publish_receivers(receivers, publish) # if receivers is non-empty, dispatch event .. # receivers_cnt = len(receivers) - (1 if self in receivers else 0) if receivers_cnt: total_receivers_cnt += receivers_cnt subscription_to_receivers[subscription] = receivers # send publish acknowledge before dispatching # if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False self._router._factory._worker._maybe_trace_rx_msg(session, publish) reply = message.Published(publish.request, publication) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = total_receivers_cnt == 0 self._router.send(session, reply) else: if self._router.is_traced and publish.correlation_is_last is None: if total_receivers_cnt == 0: publish.correlation_is_last = True else: publish.correlation_is_last = False # now actually dispatch the events! # for chunked dispatching, this will be filled with deferreds for each chunk # processed. when the complete list of deferreds is done, that means the # event has been sent out to all applicable receivers all_dl = [] if total_receivers_cnt: # list of receivers that should have received the event, but we could not # send the event, since the receiver has disappeared in the meantime vanished_receivers = [] for subscription, receivers in subscription_to_receivers.items(): storing_event = store_event and self._event_store in subscription.observers self.log.debug('dispatching for subscription={subscription}, storing_event={storing_event}', subscription=subscription, storing_event=storing_event) # for pattern-based subscriptions, the EVENT must contain # the actual topic being published to # if subscription.match != message.Subscribe.MATCH_EXACT: topic = publish.topic else: topic = None if publish.payload: msg = message.Event(subscription.id, publication, payload=publish.payload, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic, enc_algo=publish.enc_algo, enc_key=publish.enc_key, enc_serializer=publish.enc_serializer, forward_for=forward_for) else: msg = message.Event(subscription.id, publication, args=publish.args, kwargs=publish.kwargs, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic, forward_for=forward_for) # if the publish message had a correlation ID, this will also be the # correlation ID of the event message sent out msg.correlation_id = publish.correlation_id msg.correlation_uri = publish.topic msg.correlation_is_anchor = False msg.correlation_is_last = False chunk_size = self._options.event_dispatching_chunk_size if chunk_size and len(receivers) > chunk_size: self.log.debug('chunked dispatching to {receivers_size} with chunk_size={chunk_size}', receivers_size=len(receivers), chunk_size=chunk_size) else: self.log.debug('unchunked dispatching to {receivers_size} receivers', receivers_size=len(receivers)) # note that we're using one code-path for both chunked and unchunked # dispatches; the *first* chunk is always done "synchronously" (before # the first call-later) so "un-chunked mode" really just means we know # we'll be done right now and NOT do a call_later... # a Deferred that fires when all chunks are done all_d = txaio.create_future() all_dl.append(all_d) # all the event messages are the same except for the last one, which # needs to have the "is_last" flag set if we're doing a trace if self._router.is_traced: last_msg = copy.deepcopy(msg) last_msg.correlation_id = msg.correlation_id last_msg.correlation_uri = msg.correlation_uri last_msg.correlation_is_anchor = False last_msg.correlation_is_last = True def _notify_some(receivers): # we do a first pass over the proposed chunk of receivers # because not all of them will have a transport, and if this # will be the last chunk of receivers we need to figure out # which event is last... receivers_this_chunk = [] for receiver in receivers[:chunk_size]: if receiver._session_id and receiver._transport: receivers_this_chunk.append(receiver) else: vanished_receivers.append(receiver) receivers = receivers[chunk_size:] # XXX note there's still going to be some edge-cases here .. if # we are NOT the last chunk, but all the next chunk's receivers # (could be only 1 in that chunk!) vanish before we run our next # batch, then a "last" event will never go out ... # we now actually do the deliveries, but now we know which # receiver is the last one if receivers or not self._router.is_traced: # NOT the last chunk (or we're not traced so don't care) for receiver in receivers_this_chunk: # send out WAMP msg to peer self._router.send(receiver, msg) if self._event_store or storing_event: self._event_store.store_event_history(publication, subscription.id, receiver) else: # last chunk, so last receiver gets the different message for receiver in receivers_this_chunk[:-1]: self._router.send(receiver, msg) if self._event_store or storing_event: self._event_store.store_event_history(publication, subscription.id, receiver) # FIXME: I don't get the following comment and code path. when, how? and what to # do about event store? => storing_event # # we might have zero valid receivers if receivers_this_chunk: self._router.send(receivers_this_chunk[-1], last_msg) # FIXME: => storing_event if receivers: # still more to do .. return txaio.call_later(0, _notify_some, receivers) else: # all done! resolve all_d, which represents all receivers # to a single subscription matching the event txaio.resolve(all_d, None) _notify_some([ recv for recv in receivers if (me_also or recv != session) and recv != self._event_store ]) return txaio.gather(all_dl) def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ self.log.failure("Authorization failed", failure=err) if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False self._router._factory._worker._maybe_trace_rx_msg(session, publish) reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.AUTHORIZATION_FAILED, [u"failed to authorize session for publishing to topic URI '{0}': {1}".format(publish.topic, err.value)] ) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False self._router.send(session, reply) else: if self._router.is_traced: publish.correlation_is_last = True self._router._factory._worker._maybe_trace_rx_msg(session, publish) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processSubscribe(self, session, subscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processSubscribe` """ if self._router.is_traced: if not subscribe.correlation_id: subscribe.correlation_id = self._router.new_correlation_id() subscribe.correlation_is_anchor = True subscribe.correlation_is_last = False if not subscribe.correlation_uri: subscribe.correlation_uri = subscribe.topic self._router._factory._worker._maybe_trace_rx_msg(session, subscribe) # check topic URI: for SUBSCRIBE, must be valid URI (either strict or loose), and all # URI components must be non-empty for normal subscriptions, may be empty for # wildcard subscriptions and must be non-empty for all but the last component for # prefix subscriptions # if self._option_uri_strict: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_STRICT_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_STRICT_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(subscribe.topic) else: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_LOOSE_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_LOOSE_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(subscribe.topic) if not uri_is_valid: reply = message.Error(message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.INVALID_URI, [u"subscribe for invalid topic URI '{0}'".format(subscribe.topic)]) reply.correlation_id = subscribe.correlation_id reply.correlation_uri = subscribe.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) return # authorize SUBSCRIBE action # d = self._router.authorize(session, subscribe.topic, u'subscribe', options=subscribe.marshal_options()) def on_authorize_success(authorization): if not authorization[u'allow']: # error reply since session is not authorized to subscribe # replies = [message.Error(message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.NOT_AUTHORIZED, [u"session is not authorized to subscribe to topic '{0}'".format(subscribe.topic)])] replies[0].correlation_id = subscribe.correlation_id replies[0].correlation_uri = subscribe.topic replies[0].correlation_is_anchor = False replies[0].correlation_is_last = True else: # ok, session authorized to subscribe. now get the subscription # subscription, was_already_subscribed, is_first_subscriber = self._subscription_map.add_observer(session, subscribe.topic, subscribe.match, extra=SubscriptionExtra()) if not was_already_subscribed: self._session_to_subscriptions[session].add(subscription) # publish WAMP meta events, if we have a service session, but # not for the meta API itself! # if self._router._realm and \ self._router._realm.session and \ not subscription.uri.startswith(u'wamp.') and \ (is_first_subscriber or not was_already_subscribed): has_follow_up_messages = True exclude_authid = None if subscribe.forward_for: exclude_authid = [ff['authid'] for ff in subscribe.forward_for] def _publish(): service_session = self._router._realm.session if exclude_authid or self._router.is_traced: options = types.PublishOptions( correlation_id=subscribe.correlation_id, correlation_is_anchor=False, correlation_is_last=False, exclude_authid=exclude_authid, ) else: options = None if is_first_subscriber: subscription_details = { u'id': subscription.id, u'created': subscription.created, u'uri': subscription.uri, u'match': subscription.match, } service_session.publish( u'wamp.subscription.on_create', session._session_id, subscription_details, options=options, ) if not was_already_subscribed: if options: options.correlation_is_last = True service_session.publish( u'wamp.subscription.on_subscribe', session._session_id, subscription.id, options=options, ) # we postpone actual sending of meta events until we return to this client session self._reactor.callLater(0, _publish) else: has_follow_up_messages = False # check for retained events # def _get_retained_event(): if subscription.extra.retained_events: retained_events = list(subscription.extra.retained_events) retained_events.reverse() for retained_event in retained_events: authorized = False if not retained_event.publish.exclude and not retained_event.publish.eligible: authorized = True elif session._session_id in retained_event.publish.eligible and session._session_id not in retained_event.publish.exclude: authorized = True if authorized: publication = util.id() if retained_event.publish.payload: msg = message.Event(subscription.id, publication, payload=retained_event.publish.payload, enc_algo=retained_event.publish.enc_algo, enc_key=retained_event.publish.enc_key, enc_serializer=retained_event.publish.enc_serializer, publisher=retained_event.publisher, publisher_authid=retained_event.publisher_authid, publisher_authrole=retained_event.publisher_authrole, retained=True) else: msg = message.Event(subscription.id, publication, args=retained_event.publish.args, kwargs=retained_event.publish.kwargs, publisher=retained_event.publisher, publisher_authid=retained_event.publisher_authid, publisher_authrole=retained_event.publisher_authrole, retained=True) msg.correlation_id = subscribe.correlation_id msg.correlation_uri = subscribe.topic msg.correlation_is_anchor = False msg.correlation_is_last = False return [msg] return [] # acknowledge subscribe with subscription ID # replies = [message.Subscribed(subscribe.request, subscription.id)] replies[0].correlation_id = subscribe.correlation_id replies[0].correlation_uri = subscribe.topic replies[0].correlation_is_anchor = False replies[0].correlation_is_last = False if subscribe.get_retained: replies.extend(_get_retained_event()) replies[-1].correlation_is_last = not has_follow_up_messages # send out reply to subscribe requestor # [self._router.send(session, reply) for reply in replies] def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ self.log.failure("Authorization of 'subscribe' for '{uri}' failed", uri=subscribe.topic, failure=err) reply = message.Error( message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.AUTHORIZATION_FAILED, [u"failed to authorize session for subscribing to topic URI '{0}': {1}".format(subscribe.topic, err.value)] ) reply.correlation_id = subscribe.correlation_id reply.correlation_uri = subscribe.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processUnsubscribe(self, session, unsubscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processUnsubscribe` """ if self._router.is_traced: if not unsubscribe.correlation_id: unsubscribe.correlation_id = self._router.new_correlation_id() unsubscribe.correlation_is_anchor = True unsubscribe.correlation_is_last = False # get subscription by subscription ID or None (if it doesn't exist on this broker) # subscription = self._subscription_map.get_observation_by_id(unsubscribe.subscription) if subscription: if self._router.is_traced and not unsubscribe.correlation_uri: unsubscribe.correlation_uri = subscription.uri if session in subscription.observers: was_subscribed, was_last_subscriber, has_follow_up_messages = self._unsubscribe(subscription, session, unsubscribe) reply = message.Unsubscribed(unsubscribe.request) if self._router.is_traced: reply.correlation_uri = subscription.uri reply.correlation_is_last = not has_follow_up_messages else: # subscription exists on this broker, but the session that wanted to unsubscribe wasn't subscribed # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) if self._router.is_traced: reply.correlation_uri = reply.error reply.correlation_is_last = True else: # subscription doesn't even exist on this broker # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) if self._router.is_traced: reply.correlation_uri = reply.error reply.correlation_is_last = True if self._router.is_traced: self._router._factory._worker._maybe_trace_rx_msg(session, unsubscribe) reply.correlation_id = unsubscribe.correlation_id reply.correlation_is_anchor = False self._router.send(session, reply) def _unsubscribe(self, subscription, session, unsubscribe=None): # drop session from subscription observers # was_subscribed, was_last_subscriber = self._subscription_map.drop_observer(session, subscription) was_deleted = False if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: self._subscription_map.delete_observation(subscription) was_deleted = True # remove subscription from session->subscriptions map # if was_subscribed: self._session_to_subscriptions[session].discard(subscription) # publish WAMP meta events, if we have a service session, but # not for the meta API itself! # if self._router._realm and \ self._router._realm.session and \ not subscription.uri.startswith(u'wamp.') and \ (was_subscribed or was_deleted): has_follow_up_messages = True exclude_authid = None if unsubscribe and unsubscribe.forward_for: exclude_authid = [ff['authid'] for ff in unsubscribe.forward_for] def _publish(): service_session = self._router._realm.session if unsubscribe and (exclude_authid or self._router.is_traced): options = types.PublishOptions( correlation_id=unsubscribe.correlation_id, correlation_is_anchor=False, correlation_is_last=False, exclude_authid=exclude_authid, ) else: options = None if was_subscribed: service_session.publish( u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id, options=options, ) if was_deleted: if options: options.correlation_is_last = True service_session.publish( u'wamp.subscription.on_delete', session._session_id, subscription.id, options=options, ) # we postpone actual sending of meta events until we return to this client session self._reactor.callLater(0, _publish) else: has_follow_up_messages = False return was_subscribed, was_last_subscriber, has_follow_up_messages def removeSubscriber(self, subscription, session, reason=None): """ Actively unsubscribe a subscriber session from a subscription. """ was_subscribed, was_last_subscriber, _ = self._unsubscribe(subscription, session) if 'subscriber' in session._session_roles and session._session_roles['subscriber'] and session._session_roles['subscriber'].subscription_revocation: reply = message.Unsubscribed(0, subscription=subscription.id, reason=reason) reply.correlation_uri = subscription.uri self._router.send(session, reply) return was_subscribed, was_last_subscriber
class Broker(object): """ Basic WAMP broker. """ log = make_logger() def __init__(self, router, reactor, options=None): """ :param router: The router this dealer is part of. :type router: Object that implements :class:`crossbar.router.interfaces.IRouter`. :param options: Router options. :type options: Instance of :class:`crossbar.router.types.RouterOptions`. """ self._router = router self._reactor = reactor self._options = options or RouterOptions() # generator for WAMP request IDs self._request_id_gen = util.IdGenerator() # subscription map managed by this broker self._subscription_map = UriObservationMap() # map: session -> set of subscriptions (needed for detach) self._session_to_subscriptions = {} # check all topic URIs with strict rules self._option_uri_strict = self._options.uri_check == RouterOptions.URI_CHECK_STRICT # supported features from "WAMP Advanced Profile" self._role_features = role.RoleBrokerFeatures( publisher_identification=True, pattern_based_subscription=True, session_meta_api=True, subscription_meta_api=True, subscriber_blackwhite_listing=True, publisher_exclusion=True, subscription_revocation=True, event_retention=True, payload_transparency=True, payload_encryption_cryptobox=True) # store for event history if self._router._store: self._event_store = self._router._store.event_store else: self._event_store = None # if there is a store, let the store attach itself to all the subscriptions # it is configured to track if self._event_store: self._event_store.attach_subscription_map(self._subscription_map) def attach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.attach` """ if session not in self._session_to_subscriptions: self._session_to_subscriptions[session] = set() else: raise Exception(u"session with ID {} already attached".format( session._session_id)) def detach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.detach` """ if session in self._session_to_subscriptions: for subscription in self._session_to_subscriptions[session]: was_subscribed, was_last_subscriber = self._subscription_map.drop_observer( session, subscription) was_deleted = False # delete it if there are no subscribers and no retained events # if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: was_deleted = True self._subscription_map.delete_observation(subscription) # publish WAMP meta events, if we have a service session, but # not for the meta API itself! # if self._router._realm and \ self._router._realm.session and \ not subscription.uri.startswith(u'wamp.'): def _publish(): service_session = self._router._realm.session options = types.PublishOptions(correlation_id=None) if was_subscribed: service_session.publish( u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id, options=options, ) if was_deleted: service_session.publish( u'wamp.subscription.on_delete', session._session_id, subscription.id, options=options, ) # we postpone actual sending of meta events until we return to this client session self._reactor.callLater(0, _publish) del self._session_to_subscriptions[session] else: raise Exception("session with ID {} not attached".format( session._session_id)) def _filter_publish_receivers(self, receivers, publish): """ Internal helper. Does all filtering on a candidate set of Publish receivers, based on all the white/blacklist options in 'publish'. """ # filter by "eligible" receivers # if publish.eligible: # map eligible session IDs to eligible sessions eligible = set() for session_id in publish.eligible: if session_id in self._router._session_id_to_session: eligible.add( self._router._session_id_to_session[session_id]) # filter receivers for eligible sessions receivers = eligible & receivers # if "eligible_authid" we only accept receivers that have the correct authid if publish.eligible_authid: eligible = set() for aid in publish.eligible_authid: eligible.update( self._router._authid_to_sessions.get(aid, set())) receivers = receivers & eligible # if "eligible_authrole" we only accept receivers that have the correct authrole if publish.eligible_authrole: eligible = set() for ar in publish.eligible_authrole: eligible.update( self._router._authrole_to_sessions.get(ar, set())) receivers = receivers & eligible # remove "excluded" receivers # if publish.exclude: # map excluded session IDs to excluded sessions exclude = set() for s in publish.exclude: if s in self._router._session_id_to_session: exclude.add(self._router._session_id_to_session[s]) # filter receivers for excluded sessions if exclude: receivers = receivers - exclude # remove auth-id based receivers if publish.exclude_authid: for aid in publish.exclude_authid: receivers = receivers - self._router._authid_to_sessions.get( aid, set()) # remove authrole based receivers if publish.exclude_authrole: for ar in publish.exclude_authrole: receivers = receivers - self._router._authrole_to_sessions.get( ar, set()) return receivers def processPublish(self, session, publish): """ Implements :func:`crossbar.router.interfaces.IBroker.processPublish` """ if self._router.is_traced: if not publish.correlation_id: publish.correlation_id = self._router.new_correlation_id() publish.correlation_is_anchor = True if not publish.correlation_uri: publish.correlation_uri = publish.topic # check topic URI: for PUBLISH, must be valid URI (either strict or loose), and # all URI components must be non-empty if self._option_uri_strict: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(publish.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(publish.topic) if not uri_is_valid: if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [ u"publish with invalid topic URI '{0}' (URI strict checking {1})" .format(publish.topic, self._option_uri_strict) ]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) return # disallow publication to topics starting with "wamp." other than for # trusted sessions (that are sessions built into Crossbar.io routing core) # if session._authrole is not None and session._authrole != u"trusted": is_restricted = publish.topic.startswith(u"wamp.") if is_restricted: if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [ u"publish with restricted topic URI '{0}'".format( publish.topic) ]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) return # get subscriptions active on the topic published to # subscriptions = self._subscription_map.match_observations( publish.topic) # check if the event is being persisted by checking if we ourself are among the observers # on _any_ matching subscription # we've been previously added to observer lists on subscriptions ultimately from # node configuration and during the broker starts up. store_event = False if self._event_store: for subscription in subscriptions: if self._event_store in subscription.observers: store_event = True break if store_event: self.log.debug('Persisting event on topic "{topic}"', topic=publish.topic) # check if the event is to be retained by inspecting the 'retain' flag retain_event = False if publish.retain: retain_event = True # go on if (otherwise there isn't anything to do anyway): # # - there are any active subscriptions OR # - the publish is to be acknowledged OR # - the event is to be persisted OR # - the event is to be retained # if not (subscriptions or publish.acknowledge or store_event or retain_event): # the received PUBLISH message is the only one received/sent # for this WAMP action, so mark it as "last" (there is another code path below!) if self._router.is_traced and publish.correlation_is_last is None: publish.correlation_is_last = True else: # validate payload # if publish.payload is None: try: self._router.validate('event', publish.topic, publish.args, publish.kwargs) except Exception as e: if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_ARGUMENT, [ u"publish to topic URI '{0}' with invalid application payload: {1}" .format(publish.topic, e) ]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) return # authorize PUBLISH action # d = self._router.authorize(session, publish.topic, u'publish', options=publish.marshal_options()) def on_authorize_success(authorization): # the call to authorize the action _itself_ succeeded. now go on depending on whether # the action was actually authorized or not .. # if not authorization[u'allow']: if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.NOT_AUTHORIZED, [ u"session not authorized to publish to topic '{0}'" .format(publish.topic) ]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) else: # new ID for the publication # publication = util.id() # publisher disclosure # if authorization[u'disclose']: disclose = True elif (publish.topic.startswith(u"wamp.") or publish.topic.startswith(u"crossbar.")): disclose = True else: disclose = False if disclose: publisher = session._session_id publisher_authid = session._authid publisher_authrole = session._authrole else: publisher = None publisher_authid = None publisher_authrole = None # skip publisher # if publish.exclude_me is None or publish.exclude_me: me_also = False else: me_also = True # persist event (this is done only once, regardless of the number of subscriptions # the event matches on) # if store_event: self._event_store.store_event(session._session_id, publication, publish.topic, publish.args, publish.kwargs) # retain event on the topic # if retain_event: retained_event = RetainedEvent(publish, publisher, publisher_authid, publisher_authrole) observation = self._subscription_map.get_observation( publish.topic) if not observation: # No observation, lets make a new one observation = self._subscription_map.create_observation( publish.topic, extra=SubscriptionExtra()) else: # this can happen if event-history is # enabled on the topic: the event-store # creates an observation before any client # could possible hit the code above if observation.extra is None: observation.extra = SubscriptionExtra() elif not isinstance(observation.extra, SubscriptionExtra): raise Exception( "incorrect 'extra' for '{}'".format( publish.topic)) if observation.extra.retained_events: if not publish.eligible and not publish.exclude: observation.extra.retained_events = [ retained_event ] else: observation.extra.retained_events.append( retained_event) else: observation.extra.retained_events = [ retained_event ] subscription_to_receivers = {} total_receivers_cnt = 0 # iterate over all subscriptions and determine actual receivers of the event # under the respective subscription. also persist events (independent of whether # there is any actual receiver right now on the subscription) # for subscription in subscriptions: # persist event history, but check if it is persisted on the individual subscription! # if store_event and self._event_store in subscription.observers: self._event_store.store_event_history( publication, subscription.id) # initial list of receivers are all subscribers on a subscription .. # receivers = subscription.observers receivers = self._filter_publish_receivers( receivers, publish) # if receivers is non-empty, dispatch event .. # receivers_cnt = len(receivers) - (1 if self in receivers else 0) if receivers_cnt: total_receivers_cnt += receivers_cnt subscription_to_receivers[subscription] = receivers # send publish acknowledge before dispatching # if publish.acknowledge: if self._router.is_traced: publish.correlation_is_last = False reply = message.Published(publish.request, publication) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False reply.correlation_is_last = total_receivers_cnt == 0 self._router.send(session, reply) else: if self._router.is_traced and publish.correlation_is_last is None: if total_receivers_cnt == 0: publish.correlation_is_last = True else: publish.correlation_is_last = False # now actually dispatch the events! # for chunked dispatching, this will be filled with deferreds for each chunk # processed. when the complete list of deferreds is done, that means the # event has been sent out to all applicable receivers all_dl = [] if total_receivers_cnt: # list of receivers that should have received the event, but we could not # send the event, since the receiver has disappeared in the meantime vanished_receivers = [] for subscription, receivers in subscription_to_receivers.items( ): self.log.debug( 'dispatching for subscription={subscription}', subscription=subscription) # for pattern-based subscriptions, the EVENT must contain # the actual topic being published to # if subscription.match != message.Subscribe.MATCH_EXACT: topic = publish.topic else: topic = None if publish.payload: msg = message.Event( subscription.id, publication, payload=publish.payload, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic, enc_algo=publish.enc_algo, enc_key=publish.enc_key, enc_serializer=publish.enc_serializer) else: msg = message.Event( subscription.id, publication, args=publish.args, kwargs=publish.kwargs, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic) # if the publish message had a correlation ID, this will also be the # correlation ID of the event message sent out msg.correlation_id = publish.correlation_id msg.correlation_uri = publish.topic msg.correlation_is_anchor = False msg.correlation_is_last = False chunk_size = self._options.event_dispatching_chunk_size if chunk_size and len(receivers) > chunk_size: self.log.debug( 'chunked dispatching to {receivers_size} with chunk_size={chunk_size}', receivers_size=len(receivers), chunk_size=chunk_size) else: self.log.debug( 'unchunked dispatching to {receivers_size} receivers', receivers_size=len(receivers)) # note that we're using one code-path for both chunked and unchunked # dispatches; the *first* chunk is always done "synchronously" (before # the first call-later) so "un-chunked mode" really just means we know # we'll be done right now and NOT do a call_later... # a Deferred that fires when all chunks are done all_d = txaio.create_future() all_dl.append(all_d) # all the event messages are the same except for the last one, which # needs to have the "is_last" flag set if we're doing a trace if self._router.is_traced: last_msg = copy.deepcopy(msg) last_msg.correlation_id = msg.correlation_id last_msg.correlation_uri = msg.correlation_uri last_msg.correlation_is_anchor = False last_msg.correlation_is_last = True def _notify_some(receivers): # we do a first pass over the proposed chunk of receivers # because not all of them will have a transport, and if this # will be the last chunk of receivers we need to figure out # which event is last... receivers_this_chunk = [] for receiver in receivers[:chunk_size]: if (me_also or receiver != session ) and receiver != self._event_store: # the receiving subscriber session might have no transport, # or no longer be joined if receiver._session_id and receiver._transport: receivers_this_chunk.append( receiver) else: vanished_receivers.append(receiver) receivers = receivers[chunk_size:] # XXX note there's still going to be some edge-cases here .. if # we are NOT the last chunk, but all the next chunk's receivers # (could be only 1 in that chunk!) vanish before we run our next # batch, then a "last" event will never go out ... # we now actually do the deliveries, but now we know which # receiver is the last one if receivers or not self._router.is_traced: # NOT the last chunk (or we're not traced so don't care) for receiver in receivers_this_chunk: self._router.send(receiver, msg) else: # last chunk, so last receiver gets the different message for receiver in receivers_this_chunk[:-1]: self._router.send(receiver, msg) # we might have zero valid receivers if receivers_this_chunk: self._router.send( receivers_this_chunk[-1], last_msg) if receivers: # still more to do .. return txaio.call_later( 0, _notify_some, receivers) else: # all done! resolve all_d, which represents all receivers # to a single subscription matching the event txaio.resolve(all_d, None) _notify_some(list(receivers)) return txaio.gather(all_dl) def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ self.log.failure("Authorization failed", failure=err) if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.AUTHORIZATION_FAILED, [ u"failed to authorize session for publishing to topic URI '{0}': {1}" .format(publish.topic, err.value) ]) reply.correlation_id = publish.correlation_id reply.correlation_uri = publish.topic reply.correlation_is_anchor = False self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processSubscribe(self, session, subscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processSubscribe` """ if self._router.is_traced: if not subscribe.correlation_id: subscribe.correlation_id = self._router.new_correlation_id() subscribe.correlation_is_anchor = True subscribe.correlation_is_last = False if not subscribe.correlation_uri: subscribe.correlation_uri = subscribe.topic # check topic URI: for SUBSCRIBE, must be valid URI (either strict or loose), and all # URI components must be non-empty for normal subscriptions, may be empty for # wildcard subscriptions and must be non-empty for all but the last component for # prefix subscriptions # if self._option_uri_strict: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_STRICT_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_STRICT_LAST_EMPTY.match( subscribe.topic) else: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(subscribe.topic) else: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_LOOSE_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_LOOSE_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(subscribe.topic) if not uri_is_valid: reply = message.Error( message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.INVALID_URI, [ u"subscribe for invalid topic URI '{0}'".format( subscribe.topic) ]) reply.correlation_id = subscribe.correlation_id reply.correlation_uri = subscribe.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) return # authorize SUBSCRIBE action # d = self._router.authorize(session, subscribe.topic, u'subscribe', options=subscribe.marshal_options()) def on_authorize_success(authorization): if not authorization[u'allow']: # error reply since session is not authorized to subscribe # replies = [ message.Error( message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.NOT_AUTHORIZED, [ u"session is not authorized to subscribe to topic '{0}'" .format(subscribe.topic) ]) ] replies[0].correlation_id = subscribe.correlation_id replies[0].correlation_uri = subscribe.topic replies[0].correlation_is_anchor = False replies[0].correlation_is_last = True else: # ok, session authorized to subscribe. now get the subscription # subscription, was_already_subscribed, is_first_subscriber = self._subscription_map.add_observer( session, subscribe.topic, subscribe.match, extra=SubscriptionExtra()) if not was_already_subscribed: self._session_to_subscriptions[session].add(subscription) # publish WAMP meta events, if we have a service session, but # not for the meta API itself! # if self._router._realm and \ self._router._realm.session and \ not subscription.uri.startswith(u'wamp.') and \ (is_first_subscriber or not was_already_subscribed): has_follow_up_messages = True def _publish(): service_session = self._router._realm.session options = types.PublishOptions( correlation_id=subscribe.correlation_id, correlation_is_anchor=False, correlation_is_last=False, ) if is_first_subscriber: subscription_details = { u'id': subscription.id, u'created': subscription.created, u'uri': subscription.uri, u'match': subscription.match, } service_session.publish( u'wamp.subscription.on_create', session._session_id, subscription_details, options=options, ) if not was_already_subscribed: options.correlation_is_last = True service_session.publish( u'wamp.subscription.on_subscribe', session._session_id, subscription.id, options=options, ) # we postpone actual sending of meta events until we return to this client session self._reactor.callLater(0, _publish) else: has_follow_up_messages = False # check for retained events # def _get_retained_event(): if subscription.extra.retained_events: retained_events = list( subscription.extra.retained_events) retained_events.reverse() for retained_event in retained_events: authorized = False if not retained_event.publish.exclude and not retained_event.publish.eligible: authorized = True elif session._session_id in retained_event.publish.eligible and session._session_id not in retained_event.publish.exclude: authorized = True if authorized: publication = util.id() if retained_event.publish.payload: msg = message.Event( subscription.id, publication, payload=retained_event.publish.payload, enc_algo=retained_event.publish. enc_algo, enc_key=retained_event.publish.enc_key, enc_serializer=retained_event.publish. enc_serializer, publisher=retained_event.publisher, publisher_authid=retained_event. publisher_authid, publisher_authrole=retained_event. publisher_authrole, retained=True) else: msg = message.Event( subscription.id, publication, args=retained_event.publish.args, kwargs=retained_event.publish.kwargs, publisher=retained_event.publisher, publisher_authid=retained_event. publisher_authid, publisher_authrole=retained_event. publisher_authrole, retained=True) msg.correlation_id = subscribe.correlation_id msg.correlation_uri = subscribe.topic msg.correlation_is_anchor = False msg.correlation_is_last = False return [msg] return [] # acknowledge subscribe with subscription ID # replies = [ message.Subscribed(subscribe.request, subscription.id) ] replies[0].correlation_id = subscribe.correlation_id replies[0].correlation_uri = subscribe.topic replies[0].correlation_is_anchor = False replies[0].correlation_is_last = False if subscribe.get_retained: replies.extend(_get_retained_event()) replies[-1].correlation_is_last = not has_follow_up_messages # send out reply to subscribe requestor # [self._router.send(session, reply) for reply in replies] def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ self.log.failure("Authorization of 'subscribe' for '{uri}' failed", uri=subscribe.topic, failure=err) reply = message.Error( message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.AUTHORIZATION_FAILED, [ u"failed to authorize session for subscribing to topic URI '{0}': {1}" .format(subscribe.topic, err.value) ]) reply.correlation_id = subscribe.correlation_id reply.correlation_uri = subscribe.topic reply.correlation_is_anchor = False reply.correlation_is_last = True self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processUnsubscribe(self, session, unsubscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processUnsubscribe` """ if self._router.is_traced: if not unsubscribe.correlation_id: unsubscribe.correlation_id = self._router.new_correlation_id() unsubscribe.correlation_is_anchor = True unsubscribe.correlation_is_last = False # get subscription by subscription ID or None (if it doesn't exist on this broker) # subscription = self._subscription_map.get_observation_by_id( unsubscribe.subscription) if subscription: if self._router.is_traced and not unsubscribe.correlation_uri: unsubscribe.correlation_uri = subscription.uri if session in subscription.observers: was_subscribed, was_last_subscriber, has_follow_up_messages = self._unsubscribe( subscription, session, unsubscribe) reply = message.Unsubscribed(unsubscribe.request) if self._router.is_traced: reply.correlation_uri = subscription.uri reply.correlation_is_last = not has_follow_up_messages else: # subscription exists on this broker, but the session that wanted to unsubscribe wasn't subscribed # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) if self._router.is_traced: reply.correlation_uri = reply.error reply.correlation_is_last = True else: # subscription doesn't even exist on this broker # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) if self._router.is_traced: reply.correlation_uri = reply.error reply.correlation_is_last = True if self._router.is_traced: reply.correlation_id = unsubscribe.correlation_id reply.correlation_is_anchor = False self._router.send(session, reply) def _unsubscribe(self, subscription, session, unsubscribe=None): # drop session from subscription observers # was_subscribed, was_last_subscriber = self._subscription_map.drop_observer( session, subscription) was_deleted = False if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: self._subscription_map.delete_observation(subscription) was_deleted = True # remove subscription from session->subscriptions map # if was_subscribed: self._session_to_subscriptions[session].discard(subscription) # publish WAMP meta events, if we have a service session, but # not for the meta API itself! # if self._router._realm and \ self._router._realm.session and \ not subscription.uri.startswith(u'wamp.') and \ (was_subscribed or was_deleted): has_follow_up_messages = True def _publish(): service_session = self._router._realm.session if unsubscribe and self._router.is_traced: options = types.PublishOptions( correlation_id=unsubscribe.correlation_id, correlation_is_anchor=False, correlation_is_last=False) else: options = None if was_subscribed: service_session.publish( u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id, options=options, ) if was_deleted: if options: options.correlation_is_last = True service_session.publish( u'wamp.subscription.on_delete', session._session_id, subscription.id, options=options, ) # we postpone actual sending of meta events until we return to this client session self._reactor.callLater(0, _publish) else: has_follow_up_messages = False return was_subscribed, was_last_subscriber, has_follow_up_messages def removeSubscriber(self, subscription, session, reason=None): """ Actively unsubscribe a subscriber session from a subscription. """ was_subscribed, was_last_subscriber, _ = self._unsubscribe( subscription, session) if 'subscriber' in session._session_roles and session._session_roles[ 'subscriber'] and session._session_roles[ 'subscriber'].subscription_revocation: reply = message.Unsubscribed(0, subscription=subscription.id, reason=reason) reply.correlation_uri = subscription.uri self._router.send(session, reply) return was_subscribed, was_last_subscriber
class Broker(object): """ Basic WAMP broker. """ log = make_logger() def __init__(self, router, options=None): """ :param router: The router this dealer is part of. :type router: Object that implements :class:`crossbar.router.interfaces.IRouter`. :param options: Router options. :type options: Instance of :class:`crossbar.router.types.RouterOptions`. """ self._router = router self._options = options or RouterOptions() # subscription map managed by this broker self._subscription_map = UriObservationMap() # map: session -> set of subscriptions (needed for detach) self._session_to_subscriptions = {} # check all topic URIs with strict rules self._option_uri_strict = self._options.uri_check == RouterOptions.URI_CHECK_STRICT # supported features from "WAMP Advanced Profile" self._role_features = role.RoleBrokerFeatures(publisher_identification=True, pattern_based_subscription=True, session_meta_api=True, subscription_meta_api=True, subscriber_blackwhite_listing=True, publisher_exclusion=True, subscription_revocation=True, event_retention=True, payload_transparency=True, payload_encryption_cryptobox=True) # store for event history if self._router._store: self._event_store = self._router._store.event_store else: self._event_store = None # if there is a store, let the store attach itself to all the subscriptions # it is configured to track if self._event_store: self._event_store.attach_subscription_map(self._subscription_map) def attach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.attach` """ if session not in self._session_to_subscriptions: self._session_to_subscriptions[session] = set() else: raise Exception(u"session with ID {} already attached".format(session._session_id)) def detach(self, session): """ Implements :func:`crossbar.router.interfaces.IBroker.detach` """ if session in self._session_to_subscriptions: for subscription in self._session_to_subscriptions[session]: was_subscribed, was_last_subscriber = self._subscription_map.drop_observer(session, subscription) was_deleted = False # delete it if there are no subscribers and no retained events # if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: was_deleted = True self._subscription_map.delete_observation(subscription) # publish WAMP meta events # if self._router._realm: service_session = self._router._realm.session if service_session and not subscription.uri.startswith(u'wamp.'): if was_subscribed: service_session.publish(u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id) if was_deleted: service_session.publish(u'wamp.subscription.on_delete', session._session_id, subscription.id) del self._session_to_subscriptions[session] else: raise Exception("session with ID {} not attached".format(session._session_id)) def processPublish(self, session, publish): """ Implements :func:`crossbar.router.interfaces.IBroker.processPublish` """ # check topic URI: for PUBLISH, must be valid URI (either strict or loose), and # all URI components must be non-empty if self._option_uri_strict: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(publish.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(publish.topic) if not uri_is_valid: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [u"publish with invalid topic URI '{0}' (URI strict checking {1})".format(publish.topic, self._option_uri_strict)]) self._router.send(session, reply) return # disallow publication to topics starting with "wamp." and "crossbar." other than for # trusted sessions (that are sessions built into Crossbar.io) # if session._authrole is not None and session._authrole != u"trusted": is_restricted = publish.topic.startswith(u"wamp.") or publish.topic.startswith(u"crossbar.") if is_restricted: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_URI, [u"publish with restricted topic URI '{0}'".format(publish.topic)]) self._router.send(session, reply) return # get subscriptions active on the topic published to # subscriptions = self._subscription_map.match_observations(publish.topic) # check if the event is being persisted by checking if we ourself are among the observers # on _any_ matching subscription # we've been previously added to observer lists on subscriptions ultimately from # node configuration and during the broker starts up. store_event = False if self._event_store: for subscription in subscriptions: if self._event_store in subscription.observers: store_event = True break if store_event: self.log.debug('Persisting event on topic "{topic}"', topic=publish.topic) # check if the event is to be retained by inspecting the 'retain' flag retain_event = False if publish.retain: retain_event = True # go on if (otherwise there isn't anything to do anyway): # # - there are any active subscriptions OR # - the publish is to be acknowledged OR # - the event is to be persisted OR # - the event is to be retained # if subscriptions or publish.acknowledge or store_event or retain_event: # validate payload # if publish.payload is None: try: self._router.validate('event', publish.topic, publish.args, publish.kwargs) except Exception as e: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.INVALID_ARGUMENT, [u"publish to topic URI '{0}' with invalid application payload: {1}".format(publish.topic, e)]) self._router.send(session, reply) return # authorize PUBLISH action # d = self._router.authorize(session, publish.topic, u'publish') def on_authorize_success(authorization): # the call to authorize the action _itself_ succeeded. now go on depending on whether # the action was actually authorized or not .. # if not authorization[u'allow']: if publish.acknowledge: reply = message.Error(message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.NOT_AUTHORIZED, [u"session not authorized to publish to topic '{0}'".format(publish.topic)]) self._router.send(session, reply) else: # new ID for the publication # publication = util.id() # persist event (this is done only once, regardless of the number of subscriptions # the event matches on) # if store_event: self._event_store.store_event(session._session_id, publication, publish.topic, publish.args, publish.kwargs) # retain event on the topic # if retain_event: observation = self._subscription_map.get_observation(publish.topic) if not observation: # No observation, lets make a new one observation = self._subscription_map.create_observation(publish.topic, extra=SubscriptionExtra()) if observation.extra.retained_events: if not publish.eligible and not publish.exclude: observation.extra.retained_events = [publish] else: observation.extra.retained_events.append(publish) else: observation.extra.retained_events = [publish] # send publish acknowledge immediately when requested # if publish.acknowledge: reply = message.Published(publish.request, publication) self._router.send(session, reply) # publisher disclosure # if authorization[u'disclose']: disclose = True elif (publish.topic.startswith(u"wamp.") or publish.topic.startswith(u"crossbar.")): disclose = True else: disclose = False if disclose: publisher = session._session_id publisher_authid = session._authid publisher_authrole = session._authrole else: publisher = None publisher_authid = None publisher_authrole = None # skip publisher # if publish.exclude_me is None or publish.exclude_me: me_also = False else: me_also = True # iterate over all subscriptions .. # for subscription in subscriptions: # persist event history, but check if it is persisted on the individual subscription! # if store_event and self._event_store in subscription.observers: self._event_store.store_event_history(publication, subscription.id) # initial list of receivers are all subscribers on a subscription .. # receivers = subscription.observers # filter by "eligible" receivers # if publish.eligible: # map eligible session IDs to eligible sessions eligible = [] for session_id in publish.eligible: if session_id in self._router._session_id_to_session: eligible.append(self._router._session_id_to_session[session_id]) # filter receivers for eligible sessions receivers = set(eligible) & receivers # remove "excluded" receivers # if publish.exclude: # map excluded session IDs to excluded sessions exclude = [] for s in publish.exclude: if s in self._router._session_id_to_session: exclude.append(self._router._session_id_to_session[s]) # filter receivers for excluded sessions if exclude: receivers = receivers - set(exclude) # if receivers is non-empty, dispatch event .. # receivers_cnt = len(receivers) - (1 if self in receivers else 0) if receivers_cnt: # for pattern-based subscriptions, the EVENT must contain # the actual topic being published to # if subscription.match != message.Subscribe.MATCH_EXACT: topic = publish.topic else: topic = None if publish.payload: msg = message.Event(subscription.id, publication, payload=publish.payload, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic, enc_algo=publish.enc_algo, enc_key=publish.enc_key, enc_serializer=publish.enc_serializer) else: msg = message.Event(subscription.id, publication, args=publish.args, kwargs=publish.kwargs, publisher=publisher, publisher_authid=publisher_authid, publisher_authrole=publisher_authrole, topic=topic) for receiver in receivers: if (me_also or receiver != session) and receiver != self._event_store: # the receiving subscriber session # might have no transport, or no # longer be joined if receiver._session_id and receiver._transport: self._router.send(receiver, msg) def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ self.log.failure("Authorization failed", failure=err) if publish.acknowledge: reply = message.Error( message.Publish.MESSAGE_TYPE, publish.request, ApplicationError.AUTHORIZATION_FAILED, [u"failed to authorize session for publishing to topic URI '{0}': {1}".format(publish.topic, err.value)] ) self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processSubscribe(self, session, subscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processSubscribe` """ # check topic URI: for SUBSCRIBE, must be valid URI (either strict or loose), and all # URI components must be non-empty for normal subscriptions, may be empty for # wildcard subscriptions and must be non-empty for all but the last component for # prefix subscriptions # if self._option_uri_strict: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_STRICT_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_STRICT_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_STRICT_NON_EMPTY.match(subscribe.topic) else: if subscribe.match == u"wildcard": uri_is_valid = _URI_PAT_LOOSE_EMPTY.match(subscribe.topic) elif subscribe.match == u"prefix": uri_is_valid = _URI_PAT_LOOSE_LAST_EMPTY.match(subscribe.topic) else: uri_is_valid = _URI_PAT_LOOSE_NON_EMPTY.match(subscribe.topic) if not uri_is_valid: reply = message.Error(message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.INVALID_URI, [u"subscribe for invalid topic URI '{0}'".format(subscribe.topic)]) self._router.send(session, reply) return # authorize SUBSCRIBE action # d = self._router.authorize(session, subscribe.topic, u'subscribe') def on_authorize_success(authorization): if not authorization[u'allow']: # error reply since session is not authorized to subscribe # replies = [message.Error(message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.NOT_AUTHORIZED, [u"session is not authorized to subscribe to topic '{0}'".format(subscribe.topic)])] else: # ok, session authorized to subscribe. now get the subscription # subscription, was_already_subscribed, is_first_subscriber = self._subscription_map.add_observer(session, subscribe.topic, subscribe.match, extra=SubscriptionExtra()) if not was_already_subscribed: self._session_to_subscriptions[session].add(subscription) # publish WAMP meta events # if self._router._realm: service_session = self._router._realm.session if service_session and not subscription.uri.startswith(u'wamp.'): if is_first_subscriber: subscription_details = { u'id': subscription.id, u'created': subscription.created, u'uri': subscription.uri, u'match': subscription.match, } service_session.publish(u'wamp.subscription.on_create', session._session_id, subscription_details) if not was_already_subscribed: service_session.publish(u'wamp.subscription.on_subscribe', session._session_id, subscription.id) # check for retained events # def _get_retained_event(): if subscription.extra.retained_events: retained_events = list(subscription.extra.retained_events) retained_events.reverse() for publish in retained_events: authorised = False if not publish.exclude and not publish.eligible: authorised = True elif session._session_id in publish.eligible and session._session_id not in publish.exclude: authorised = True if authorised: publication = util.id() if publish.payload: msg = message.Event(subscription.id, publication, payload=publish.payload, retained=True, enc_algo=publish.enc_algo, enc_key=publish.enc_key, enc_serializer=publish.enc_serializer) else: msg = message.Event(subscription.id, publication, args=publish.args, kwargs=publish.kwargs, retained=True) return [msg] return [] # acknowledge subscribe with subscription ID # replies = [message.Subscribed(subscribe.request, subscription.id)] if subscribe.get_retained: replies.extend(_get_retained_event()) # send out reply to subscribe requestor # [self._router.send(session, reply) for reply in replies] def on_authorize_error(err): """ the call to authorize the action _itself_ failed (note this is different from the call to authorize succeed, but the authorization being denied) """ # XXX same as another code-block, can we collapse? self.log.failure("Authorization failed", failure=err) reply = message.Error( message.Subscribe.MESSAGE_TYPE, subscribe.request, ApplicationError.AUTHORIZATION_FAILED, [u"failed to authorize session for subscribing to topic URI '{0}': {1}".format(subscribe.topic, err.value)] ) self._router.send(session, reply) txaio.add_callbacks(d, on_authorize_success, on_authorize_error) def processUnsubscribe(self, session, unsubscribe): """ Implements :func:`crossbar.router.interfaces.IBroker.processUnsubscribe` """ # get subscription by subscription ID or None (if it doesn't exist on this broker) # subscription = self._subscription_map.get_observation_by_id(unsubscribe.subscription) if subscription: if session in subscription.observers: was_subscribed, was_last_subscriber = self._unsubscribe(subscription, session) reply = message.Unsubscribed(unsubscribe.request) else: # subscription exists on this broker, but the session that wanted to unsubscribe wasn't subscribed # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) else: # subscription doesn't even exist on this broker # reply = message.Error(message.Unsubscribe.MESSAGE_TYPE, unsubscribe.request, ApplicationError.NO_SUCH_SUBSCRIPTION) self._router.send(session, reply) def _unsubscribe(self, subscription, session): # drop session from subscription observers # was_subscribed, was_last_subscriber = self._subscription_map.drop_observer(session, subscription) was_deleted = False if was_subscribed and was_last_subscriber and not subscription.extra.retained_events: was_deleted = True self._subscription_map.delete_observation(subscription) # remove subscription from session->subscriptions map # if was_subscribed: self._session_to_subscriptions[session].discard(subscription) # publish WAMP meta events # if self._router._realm: service_session = self._router._realm.session if service_session and not subscription.uri.startswith(u'wamp.'): if was_subscribed: service_session.publish(u'wamp.subscription.on_unsubscribe', session._session_id, subscription.id) if was_deleted: service_session.publish(u'wamp.subscription.on_delete', session._session_id, subscription.id) return was_subscribed, was_last_subscriber def removeSubscriber(self, subscription, session, reason=None): """ Actively unsubscribe a subscriber session from a subscription. """ was_subscribed, was_last_subscriber = self._unsubscribe(subscription, session) if 'subscriber' in session._session_roles and session._session_roles['subscriber'] and session._session_roles['subscriber'].subscription_revocation: reply = message.Unsubscribed(0, subscription=subscription.id, reason=reason) self._router.send(session, reply) return was_subscribed, was_last_subscriber