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
