Mercurial > libervia-backend
view sat/plugins/plugin_xep_0060.py @ 3836:e183f1fbfa8d
doc (cli/pubsub): add doc for ``reference`` subcommand:
rel 369
author | Goffi <goffi@goffi.org> |
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date | Sun, 10 Jul 2022 16:15:09 +0200 |
parents | 853cbaf56e9e |
children | bc24ce903835 |
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#!/usr/bin/env python3 # SàT plugin for Publish-Subscribe (xep-0060) # Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org) # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Affero General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU Affero General Public License for more details. # You should have received a copy of the GNU Affero General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. from collections import namedtuple from functools import reduce from typing import Any, Dict, List, Optional, Tuple, Union import urllib.error import urllib.parse import urllib.request from twisted.internet import defer, reactor from twisted.words.protocols.jabber import error, jid from twisted.words.xish import domish from wokkel import disco from wokkel import data_form from wokkel import pubsub from wokkel import rsm from wokkel import mam from zope.interface import implementer from sat.core import exceptions from sat.core.constants import Const as C from sat.core.core_types import SatXMPPEntity from sat.core.i18n import _ from sat.core.log import getLogger from sat.tools import utils from sat.tools import sat_defer from sat.tools import xml_tools from sat.tools.common import data_format log = getLogger(__name__) PLUGIN_INFO = { C.PI_NAME: "Publish-Subscribe", C.PI_IMPORT_NAME: "XEP-0060", C.PI_TYPE: "XEP", C.PI_MODES: C.PLUG_MODE_BOTH, C.PI_PROTOCOLS: ["XEP-0060"], C.PI_DEPENDENCIES: [], C.PI_RECOMMENDATIONS: ["XEP-0059", "XEP-0313"], C.PI_MAIN: "XEP_0060", C.PI_HANDLER: "yes", C.PI_DESCRIPTION: _("""Implementation of PubSub Protocol"""), } UNSPECIFIED = "unspecified error" Extra = namedtuple("Extra", ("rsm_request", "extra")) # rsm_request is the rsm.RSMRequest build with rsm_ prefixed keys, or None # extra is a potentially empty dict TIMEOUT = 30 # minimum features that a pubsub service must have to be selectable as default DEFAULT_PUBSUB_MIN_FEAT = { 'http://jabber.org/protocol/pubsub#persistent-items', 'http://jabber.org/protocol/pubsub#publish', 'http://jabber.org/protocol/pubsub#retract-items', } class XEP_0060(object): OPT_ACCESS_MODEL = "pubsub#access_model" OPT_PERSIST_ITEMS = "pubsub#persist_items" OPT_MAX_ITEMS = "pubsub#max_items" OPT_DELIVER_PAYLOADS = "pubsub#deliver_payloads" OPT_SEND_ITEM_SUBSCRIBE = "pubsub#send_item_subscribe" OPT_NODE_TYPE = "pubsub#node_type" OPT_SUBSCRIPTION_TYPE = "pubsub#subscription_type" OPT_SUBSCRIPTION_DEPTH = "pubsub#subscription_depth" OPT_ROSTER_GROUPS_ALLOWED = "pubsub#roster_groups_allowed" OPT_PUBLISH_MODEL = "pubsub#publish_model" OPT_OVERWRITE_POLICY = "pubsub#overwrite_policy" ACCESS_OPEN = "open" ACCESS_PRESENCE = "presence" ACCESS_ROSTER = "roster" ACCESS_PUBLISHER_ROSTER = "publisher-roster" ACCESS_AUTHORIZE = "authorize" ACCESS_WHITELIST = "whitelist" PUBLISH_MODEL_PUBLISHERS = "publishers" PUBLISH_MODEL_SUBSCRIBERS = "subscribers" PUBLISH_MODEL_OPEN = "open" OWPOL_ORIGINAL = "original_publisher" OWPOL_ANY_PUB = "any_publisher" ID_SINGLETON = "current" EXTRA_PUBLISH_OPTIONS = "publish_options" EXTRA_ON_PRECOND_NOT_MET = "on_precondition_not_met" # extra disco needed for RSM, cf. XEP-0060 § 6.5.4 DISCO_RSM = "http://jabber.org/protocol/pubsub#rsm" def __init__(self, host): log.info(_("PubSub plugin initialization")) self.host = host self._rsm = host.plugins.get("XEP-0059") self._mam = host.plugins.get("XEP-0313") self._node_cb = {} # dictionnary of callbacks for node (key: node, value: list of callbacks) self.rt_sessions = sat_defer.RTDeferredSessions() host.bridge.addMethod( "psNodeCreate", ".plugin", in_sign="ssa{ss}s", out_sign="s", method=self._createNode, async_=True, ) host.bridge.addMethod( "psNodeConfigurationGet", ".plugin", in_sign="sss", out_sign="a{ss}", method=self._getNodeConfiguration, async_=True, ) host.bridge.addMethod( "psNodeConfigurationSet", ".plugin", in_sign="ssa{ss}s", out_sign="", method=self._setNodeConfiguration, async_=True, ) host.bridge.addMethod( "psNodeAffiliationsGet", ".plugin", in_sign="sss", out_sign="a{ss}", method=self._getNodeAffiliations, async_=True, ) host.bridge.addMethod( "psNodeAffiliationsSet", ".plugin", in_sign="ssa{ss}s", out_sign="", method=self._setNodeAffiliations, async_=True, ) host.bridge.addMethod( "psNodeSubscriptionsGet", ".plugin", in_sign="sss", out_sign="a{ss}", method=self._getNodeSubscriptions, async_=True, ) host.bridge.addMethod( "psNodeSubscriptionsSet", ".plugin", in_sign="ssa{ss}s", out_sign="", method=self._setNodeSubscriptions, async_=True, ) host.bridge.addMethod( "psNodePurge", ".plugin", in_sign="sss", out_sign="", method=self._purgeNode, async_=True, ) host.bridge.addMethod( "psNodeDelete", ".plugin", in_sign="sss", out_sign="", method=self._deleteNode, async_=True, ) host.bridge.addMethod( "psNodeWatchAdd", ".plugin", in_sign="sss", out_sign="", method=self._addWatch, async_=False, ) host.bridge.addMethod( "psNodeWatchRemove", ".plugin", in_sign="sss", out_sign="", method=self._removeWatch, async_=False, ) host.bridge.addMethod( "psAffiliationsGet", ".plugin", in_sign="sss", out_sign="a{ss}", method=self._getAffiliations, async_=True, ) host.bridge.addMethod( "psItemsGet", ".plugin", in_sign="ssiassss", out_sign="s", method=self._getItems, async_=True, ) host.bridge.addMethod( "psItemSend", ".plugin", in_sign="ssssss", out_sign="s", method=self._sendItem, async_=True, ) host.bridge.addMethod( "psItemsSend", ".plugin", in_sign="ssasss", out_sign="as", method=self._sendItems, async_=True, ) host.bridge.addMethod( "psItemRetract", ".plugin", in_sign="sssbs", out_sign="", method=self._retractItem, async_=True, ) host.bridge.addMethod( "psItemsRetract", ".plugin", in_sign="ssasbs", out_sign="", method=self._retractItems, async_=True, ) host.bridge.addMethod( "psItemRename", ".plugin", in_sign="sssss", out_sign="", method=self._renameItem, async_=True, ) host.bridge.addMethod( "psSubscribe", ".plugin", in_sign="ssss", out_sign="s", method=self._subscribe, async_=True, ) host.bridge.addMethod( "psUnsubscribe", ".plugin", in_sign="sss", out_sign="", method=self._unsubscribe, async_=True, ) host.bridge.addMethod( "psSubscriptionsGet", ".plugin", in_sign="sss", out_sign="s", method=self._subscriptions, async_=True, ) host.bridge.addMethod( "psSubscribeToMany", ".plugin", in_sign="a(ss)sa{ss}s", out_sign="s", method=self._subscribeToMany, ) host.bridge.addMethod( "psGetSubscribeRTResult", ".plugin", in_sign="ss", out_sign="(ua(sss))", method=self._manySubscribeRTResult, async_=True, ) host.bridge.addMethod( "psGetFromMany", ".plugin", in_sign="a(ss)iss", out_sign="s", method=self._getFromMany, ) host.bridge.addMethod( "psGetFromManyRTResult", ".plugin", in_sign="ss", out_sign="(ua(sssasa{ss}))", method=self._getFromManyRTResult, async_=True, ) # high level observer method host.bridge.addSignal( "psEvent", ".plugin", signature="ssssss" ) # args: category, service(jid), node, type (C.PS_ITEMS, C.PS_DELETE), data, profile # low level observer method, used if service/node is in watching list (see psNodeWatch* methods) host.bridge.addSignal( "psEventRaw", ".plugin", signature="sssass" ) # args: service(jid), node, type (C.PS_ITEMS, C.PS_DELETE), list of item_xml, profile def getHandler(self, client): client.pubsub_client = SatPubSubClient(self.host, self) return client.pubsub_client async def profileConnected(self, client): client.pubsub_watching = set() try: client.pubsub_service = jid.JID( self.host.memory.getConfig("", "pubsub_service") ) except RuntimeError: log.info( _( "Can't retrieve pubsub_service from conf, we'll use first one that " "we find" ) ) pubsub_services = await self.host.findServiceEntities( client, "pubsub", "service" ) for service_jid in pubsub_services: infos = await self.host.memory.disco.getInfos(client, service_jid) if not DEFAULT_PUBSUB_MIN_FEAT.issubset(infos.features): continue names = {(n or "").lower() for n in infos.identities.values()} if "libervia pubsub service" in names: # this is the name of Libervia's side project pubsub service, we know # that it is a suitable default pubsub service client.pubsub_service = service_jid break categories = {(i[0] or "").lower() for i in infos.identities.keys()} if "gateway" in categories or "gateway" in names: # we don't want to use a gateway as default pubsub service continue if "jabber:iq:register" in infos.features: # may be present on gateways, and we don't want a service # where registration is needed continue client.pubsub_service = service_jid break else: client.pubsub_service = None pubsub_service_str = ( client.pubsub_service.full() if client.pubsub_service else "PEP" ) log.info(f"default pubsub service: {pubsub_service_str}") def getFeatures(self, profile): try: client = self.host.getClient(profile) except exceptions.ProfileNotSetError: return {} try: return { "service": client.pubsub_service.full() if client.pubsub_service is not None else "" } except AttributeError: if self.host.isConnected(profile): log.debug("Profile is not connected, service is not checked yet") else: log.error("Service should be available !") return {} def parseExtra(self, extra): """Parse extra dictionnary used bridge's extra dictionnaries @param extra(dict): extra data used to configure request @return(Extra): filled Extra instance """ if extra is None: rsm_request = None extra = {} else: # order-by if C.KEY_ORDER_BY in extra: # FIXME: we temporarily manage only one level of ordering # we need to switch to a fully serialised extra data # to be able to encode a whole ordered list extra[C.KEY_ORDER_BY] = [extra.pop(C.KEY_ORDER_BY)] # rsm if self._rsm is None: rsm_request = None else: rsm_request = self._rsm.parseExtra(extra) # mam if self._mam is None: mam_request = None else: mam_request = self._mam.parseExtra(extra, with_rsm=False) if mam_request is not None: assert "mam" not in extra extra["mam"] = mam_request return Extra(rsm_request, extra) def addManagedNode(self, node, **kwargs): """Add a handler for a node @param node(unicode): node to monitor all node *prefixed* with this one will be triggered @param **kwargs: method(s) to call when the node is found the method must be named after PubSub constants in lower case and suffixed with "_cb" e.g.: "items_cb" for C.PS_ITEMS, "delete_cb" for C.PS_DELETE note: only C.PS_ITEMS and C.PS_DELETE are implemented so far """ assert node is not None assert kwargs callbacks = self._node_cb.setdefault(node, {}) for event, cb in kwargs.items(): event_name = event[:-3] assert event_name in C.PS_EVENTS callbacks.setdefault(event_name, []).append(cb) def removeManagedNode(self, node, *args): """Add a handler for a node @param node(unicode): node to monitor @param *args: callback(s) to remove """ assert args try: registred_cb = self._node_cb[node] except KeyError: pass else: for callback in args: for event, cb_list in registred_cb.items(): try: cb_list.remove(callback) except ValueError: pass else: log.debug( "removed callback {cb} for event {event} on node {node}".format( cb=callback, event=event, node=node ) ) if not cb_list: del registred_cb[event] if not registred_cb: del self._node_cb[node] return log.error( "Trying to remove inexistant callback {cb} for node {node}".format( cb=callback, node=node ) ) # def listNodes(self, service, nodeIdentifier='', profile=C.PROF_KEY_NONE): # """Retrieve the name of the nodes that are accessible on the target service. # @param service (JID): target service # @param nodeIdentifier (str): the parent node name (leave empty to retrieve first-level nodes) # @param profile (str): %(doc_profile)s # @return: deferred which fire a list of nodes # """ # client = self.host.getClient(profile) # d = self.host.getDiscoItems(client, service, nodeIdentifier) # d.addCallback(lambda result: [item.getAttribute('node') for item in result.toElement().children if item.hasAttribute('node')]) # return d # def listSubscribedNodes(self, service, nodeIdentifier='', filter_='subscribed', profile=C.PROF_KEY_NONE): # """Retrieve the name of the nodes to which the profile is subscribed on the target service. # @param service (JID): target service # @param nodeIdentifier (str): the parent node name (leave empty to retrieve all subscriptions) # @param filter_ (str): filter the result according to the given subscription type: # - None: do not filter # - 'pending': subscription has not been approved yet by the node owner # - 'unconfigured': subscription options have not been configured yet # - 'subscribed': subscription is complete # @param profile (str): %(doc_profile)s # @return: Deferred list[str] # """ # d = self.subscriptions(service, nodeIdentifier, profile_key=profile) # d.addCallback(lambda subs: [sub.getAttribute('node') for sub in subs if sub.getAttribute('subscription') == filter_]) # return d def _sendItem(self, service, nodeIdentifier, payload, item_id=None, extra_ser="", profile_key=C.PROF_KEY_NONE): client = self.host.getClient(profile_key) service = None if not service else jid.JID(service) payload = xml_tools.parse(payload) extra = data_format.deserialise(extra_ser) d = defer.ensureDeferred(self.sendItem( client, service, nodeIdentifier, payload, item_id or None, extra )) d.addCallback(lambda ret: ret or "") return d def _sendItems(self, service, nodeIdentifier, items, extra_ser=None, profile_key=C.PROF_KEY_NONE): client = self.host.getClient(profile_key) service = None if not service else jid.JID(service) try: items = [xml_tools.parse(item) for item in items] except Exception as e: raise exceptions.DataError(_("Can't parse items: {msg}").format( msg=e)) extra = data_format.deserialise(extra_ser) return defer.ensureDeferred(self.sendItems( client, service, nodeIdentifier, items, extra )) async def sendItem( self, client, service, nodeIdentifier, payload, item_id=None, extra=None ): """High level method to send one item @param service(jid.JID, None): service to send the item to None to use PEP @param NodeIdentifier(unicode): PubSub node to use @param payload(domish.Element): payload of the item to send @param item_id(unicode, None): id to use or None to create one @param extra(dict, None): extra option, not used yet @return (unicode, None): id of the created item """ assert isinstance(payload, domish.Element) item_elt = domish.Element((pubsub.NS_PUBSUB, 'item')) if item_id is not None: item_elt['id'] = item_id item_elt.addChild(payload) published_ids = await self.sendItems( client, service, nodeIdentifier, [item_elt], extra ) try: return published_ids[0] except IndexError: return item_id async def sendItems( self, client: SatXMPPEntity, service: jid.JID, nodeIdentifier: str, items: List[domish.Element], extra: Optional[Dict[str, Any]] = None ) -> List[str]: """High level method to send several items at once @param service: service to send the item to None to use PEP @param NodeIdentifier: PubSub node to use @param items: whole item elements to send, "id" will be used if set @param extra: extra options. Key can be: - self.EXTRA_PUBLISH_OPTIONS(dict): publish options, cf. XEP-0060 § 7.1.5 the dict maps option name to value(s) - self.EXTRA_ON_PRECOND_NOT_MET(str): policy to have when publishing is failing du to failing precondition. Value can be: * raise (default): raise the exception * publish_without_options: re-publish without the publish-options. A warning will be logged showing that the publish-options could not be used @return: ids of the created items """ if extra is None: extra = {} parsed_items = [] for item in items: if item.name != 'item': raise exceptions.DataError(_("Invalid item: {xml}").format(item.toXml())) item_id = item.getAttribute("id") parsed_items.append(pubsub.Item(id=item_id, payload=item.firstChildElement())) publish_options = extra.get(self.EXTRA_PUBLISH_OPTIONS) try: iq_result = await self.publish( client, service, nodeIdentifier, parsed_items, options=publish_options) except error.StanzaError as e: if ((e.condition == 'conflict' and e.appCondition and e.appCondition.name == 'precondition-not-met' and publish_options is not None)): # this usually happens when publish-options can't be set policy = extra.get(self.EXTRA_ON_PRECOND_NOT_MET, 'raise') if policy == 'raise': raise e elif policy == 'publish_without_options': log.warning(_( "Can't use publish-options ({options}) on node {node}, " "re-publishing without them: {reason}").format( options=', '.join(f'{k} = {v}' for k,v in publish_options.items()), node=nodeIdentifier, reason=e, ) ) iq_result = await self.publish( client, service, nodeIdentifier, parsed_items) else: raise exceptions.InternalError( f"Invalid policy in extra's {self.EXTRA_ON_PRECOND_NOT_MET!r}: " f"{policy}" ) else: raise e try: return [item['id'] for item in iq_result.pubsub.publish.elements(pubsub.NS_PUBSUB, 'item')] except AttributeError: return [] async def publish( self, client: SatXMPPEntity, service: jid.JID, nodeIdentifier: str, items: Optional[List[domish.Element]] = None, options: Optional[dict] = None ) -> List[str]: published_ids = await client.pubsub_client.publish( service, nodeIdentifier, items, client.pubsub_client.parent.jid, options=options ) await self.host.trigger.asyncPoint( "XEP-0060_publish", client, service, nodeIdentifier, items, options, published_ids ) return published_ids def _unwrapMAMMessage(self, message_elt): try: item_elt = reduce( lambda elt, ns_name: next(elt.elements(*ns_name)), (message_elt, (mam.NS_MAM, "result"), (C.NS_FORWARD, "forwarded"), (C.NS_CLIENT, "message"), ("http://jabber.org/protocol/pubsub#event", "event"), ("http://jabber.org/protocol/pubsub#event", "items"), ("http://jabber.org/protocol/pubsub#event", "item"), )) except StopIteration: raise exceptions.DataError("Can't find Item in MAM message element") return item_elt def serialiseItems(self, items_data): items, metadata = items_data metadata['items'] = items return data_format.serialise(metadata) def _getItems(self, service="", node="", max_items=10, item_ids=None, sub_id=None, extra="", profile_key=C.PROF_KEY_NONE): """Get items from pubsub node @param max_items(int): maximum number of item to get, C.NO_LIMIT for no limit """ client = self.host.getClient(profile_key) service = jid.JID(service) if service else None max_items = None if max_items == C.NO_LIMIT else max_items extra = self.parseExtra(data_format.deserialise(extra)) d = defer.ensureDeferred(self.getItems( client, service, node, max_items, item_ids, sub_id or None, extra.rsm_request, extra.extra, )) d.addCallback(self.transItemsData) d.addCallback(self.serialiseItems) return d async def getItems( self, client: SatXMPPEntity, service: Optional[jid.JID], node: str, max_items: Optional[int] = None, item_ids: Optional[List[str]] = None, sub_id: Optional[str] = None, rsm_request: Optional[rsm.RSMRequest] = None, extra: Optional[dict] = None ) -> Tuple[List[dict], dict]: """Retrieve pubsub items from a node. @param service (JID, None): pubsub service. @param node (str): node id. @param max_items (int): optional limit on the number of retrieved items. @param item_ids (list[str]): identifiers of the items to be retrieved (can't be used with rsm_request). @param sub_id (str): optional subscription identifier. @param rsm_request (rsm.RSMRequest): RSM request data @return: a deferred couple (list[dict], dict) containing: - list of items - metadata with the following keys: - rsm_first, rsm_last, rsm_count, rsm_index: first, last, count and index value of RSMResponse - service, node: service and node used """ if item_ids and max_items is not None: max_items = None if rsm_request and item_ids: raise ValueError("items_id can't be used with rsm") if extra is None: extra = {} cont, ret = await self.host.trigger.asyncReturnPoint( "XEP-0060_getItems", client, service, node, max_items, item_ids, sub_id, rsm_request, extra ) if not cont: return ret try: mam_query = extra["mam"] except KeyError: d = client.pubsub_client.items( service = service, nodeIdentifier = node, maxItems = max_items, subscriptionIdentifier = sub_id, sender = None, itemIdentifiers = item_ids, orderBy = extra.get(C.KEY_ORDER_BY), rsm_request = rsm_request ) # we have no MAM data here, so we add None d.addErrback(sat_defer.stanza2NotFound) d.addTimeout(TIMEOUT, reactor) items, rsm_response = await d mam_response = None else: # if mam is requested, we have to do a totally different query if self._mam is None: raise exceptions.NotFound("MAM (XEP-0313) plugin is not available") if max_items is not None: raise exceptions.DataError("max_items parameter can't be used with MAM") if item_ids: raise exceptions.DataError("items_ids parameter can't be used with MAM") if mam_query.node is None: mam_query.node = node elif mam_query.node != node: raise exceptions.DataError( "MAM query node is incoherent with getItems's node" ) if mam_query.rsm is None: mam_query.rsm = rsm_request else: if mam_query.rsm != rsm_request: raise exceptions.DataError( "Conflict between RSM request and MAM's RSM request" ) items, rsm_response, mam_response = await self._mam.getArchives( client, mam_query, service, self._unwrapMAMMessage ) try: subscribe = C.bool(extra["subscribe"]) except KeyError: subscribe = False if subscribe: try: await self.subscribe(client, service, node) except error.StanzaError as e: log.warning( f"Could not subscribe to node {node} on service {service}: {e}" ) # TODO: handle mam_response service_jid = service if service else client.jid.userhostJID() metadata = { "service": service_jid, "node": node, "uri": self.getNodeURI(service_jid, node), } if mam_response is not None: # mam_response is a dict with "complete" and "stable" keys # we can put them directly in metadata metadata.update(mam_response) if rsm_request is not None and rsm_response is not None: metadata['rsm'] = rsm_response.toDict() if mam_response is None: index = rsm_response.index count = rsm_response.count if index is None or count is None: # we don't have enough information to know if the data is complete # or not metadata["complete"] = None else: # normally we have a strict equality here but XEP-0059 states # that index MAY be approximative, so just in case… metadata["complete"] = index + len(items) >= count return (items, metadata) # @defer.inlineCallbacks # def getItemsFromMany(self, service, data, max_items=None, sub_id=None, rsm=None, profile_key=C.PROF_KEY_NONE): # """Massively retrieve pubsub items from many nodes. # @param service (JID): target service. # @param data (dict): dictionnary binding some arbitrary keys to the node identifiers. # @param max_items (int): optional limit on the number of retrieved items *per node*. # @param sub_id (str): optional subscription identifier. # @param rsm (dict): RSM request data # @param profile_key (str): %(doc_profile_key)s # @return: a deferred dict with: # - key: a value in (a subset of) data.keys() # - couple (list[dict], dict) containing: # - list of items # - RSM response data # """ # client = self.host.getClient(profile_key) # found_nodes = yield self.listNodes(service, profile=client.profile) # d_dict = {} # for publisher, node in data.items(): # if node not in found_nodes: # log.debug(u"Skip the items retrieval for [{node}]: node doesn't exist".format(node=node)) # continue # avoid pubsub "item-not-found" error # d_dict[publisher] = self.getItems(service, node, max_items, None, sub_id, rsm, client.profile) # defer.returnValue(d_dict) def getOptions(self, service, nodeIdentifier, subscriber, subscriptionIdentifier=None, profile_key=C.PROF_KEY_NONE): client = self.host.getClient(profile_key) return client.pubsub_client.getOptions( service, nodeIdentifier, subscriber, subscriptionIdentifier ) def setOptions(self, service, nodeIdentifier, subscriber, options, subscriptionIdentifier=None, profile_key=C.PROF_KEY_NONE): client = self.host.getClient(profile_key) return client.pubsub_client.setOptions( service, nodeIdentifier, subscriber, options, subscriptionIdentifier ) def _createNode(self, service_s, nodeIdentifier, options, profile_key): client = self.host.getClient(profile_key) return self.createNode( client, jid.JID(service_s) if service_s else None, nodeIdentifier, options ) def createNode(self, client, service, nodeIdentifier=None, options=None): """Create a new node @param service(jid.JID): PubSub service, @param NodeIdentifier(unicode, None): node name use None to create instant node (identifier will be returned by this method) @param option(dict[unicode, unicode], None): node configuration options @return (unicode): identifier of the created node (may be different from requested name) """ # TODO: if pubsub service doesn't hande publish-options, configure it in a second time return client.pubsub_client.createNode(service, nodeIdentifier, options) @defer.inlineCallbacks def createIfNewNode(self, client, service, nodeIdentifier, options=None): """Helper method similar to createNode, but will not fail in case of conflict""" try: yield self.createNode(client, service, nodeIdentifier, options) except error.StanzaError as e: if e.condition == "conflict": pass else: raise e def _getNodeConfiguration(self, service_s, nodeIdentifier, profile_key): client = self.host.getClient(profile_key) d = self.getConfiguration( client, jid.JID(service_s) if service_s else None, nodeIdentifier ) def serialize(form): # FIXME: better more generic dataform serialisation should be available in SàT return {f.var: str(f.value) for f in list(form.fields.values())} d.addCallback(serialize) return d def getConfiguration(self, client, service, nodeIdentifier): request = pubsub.PubSubRequest("configureGet") request.recipient = service request.nodeIdentifier = nodeIdentifier def cb(iq): form = data_form.findForm(iq.pubsub.configure, pubsub.NS_PUBSUB_NODE_CONFIG) form.typeCheck() return form d = request.send(client.xmlstream) d.addCallback(cb) return d def _setNodeConfiguration(self, service_s, nodeIdentifier, options, profile_key): client = self.host.getClient(profile_key) d = self.setConfiguration( client, jid.JID(service_s) if service_s else None, nodeIdentifier, options ) return d def setConfiguration(self, client, service, nodeIdentifier, options): request = pubsub.PubSubRequest("configureSet") request.recipient = service request.nodeIdentifier = nodeIdentifier form = data_form.Form( formType="submit", formNamespace=pubsub.NS_PUBSUB_NODE_CONFIG ) form.makeFields(options) request.options = form d = request.send(client.xmlstream) return d def _getAffiliations(self, service_s, nodeIdentifier, profile_key): client = self.host.getClient(profile_key) d = self.getAffiliations( client, jid.JID(service_s) if service_s else None, nodeIdentifier or None ) return d def getAffiliations(self, client, service, nodeIdentifier=None): """Retrieve affiliations of an entity @param nodeIdentifier(unicode, None): node to get affiliation from None to get all nodes affiliations for this service """ request = pubsub.PubSubRequest("affiliations") request.recipient = service request.nodeIdentifier = nodeIdentifier def cb(iq_elt): try: affiliations_elt = next( iq_elt.pubsub.elements((pubsub.NS_PUBSUB, "affiliations")) ) except StopIteration: raise ValueError( _("Invalid result: missing <affiliations> element: {}").format( iq_elt.toXml ) ) try: return { e["node"]: e["affiliation"] for e in affiliations_elt.elements((pubsub.NS_PUBSUB, "affiliation")) } except KeyError: raise ValueError( _("Invalid result: bad <affiliation> element: {}").format( iq_elt.toXml ) ) d = request.send(client.xmlstream) d.addCallback(cb) return d def _getNodeAffiliations(self, service_s, nodeIdentifier, profile_key): client = self.host.getClient(profile_key) d = self.getNodeAffiliations( client, jid.JID(service_s) if service_s else None, nodeIdentifier ) d.addCallback( lambda affiliations: {j.full(): a for j, a in affiliations.items()} ) return d def getNodeAffiliations(self, client, service, nodeIdentifier): """Retrieve affiliations of a node owned by profile""" request = pubsub.PubSubRequest("affiliationsGet") request.recipient = service request.nodeIdentifier = nodeIdentifier def cb(iq_elt): try: affiliations_elt = next( iq_elt.pubsub.elements((pubsub.NS_PUBSUB_OWNER, "affiliations")) ) except StopIteration: raise ValueError( _("Invalid result: missing <affiliations> element: {}").format( iq_elt.toXml ) ) try: return { jid.JID(e["jid"]): e["affiliation"] for e in affiliations_elt.elements( (pubsub.NS_PUBSUB_OWNER, "affiliation") ) } except KeyError: raise ValueError( _("Invalid result: bad <affiliation> element: {}").format( iq_elt.toXml ) ) d = request.send(client.xmlstream) d.addCallback(cb) return d def _setNodeAffiliations( self, service_s, nodeIdentifier, affiliations, profile_key=C.PROF_KEY_NONE ): client = self.host.getClient(profile_key) affiliations = { jid.JID(jid_): affiliation for jid_, affiliation in affiliations.items() } d = self.setNodeAffiliations( client, jid.JID(service_s) if service_s else None, nodeIdentifier, affiliations, ) return d def setNodeAffiliations(self, client, service, nodeIdentifier, affiliations): """Update affiliations of a node owned by profile @param affiliations(dict[jid.JID, unicode]): affiliations to set check https://xmpp.org/extensions/xep-0060.html#affiliations for a list of possible affiliations """ request = pubsub.PubSubRequest("affiliationsSet") request.recipient = service request.nodeIdentifier = nodeIdentifier request.affiliations = affiliations d = request.send(client.xmlstream) return d def _purgeNode(self, service_s, nodeIdentifier, profile_key): client = self.host.getClient(profile_key) return self.purgeNode( client, jid.JID(service_s) if service_s else None, nodeIdentifier ) def purgeNode(self, client, service, nodeIdentifier): return client.pubsub_client.purgeNode(service, nodeIdentifier) def _deleteNode(self, service_s, nodeIdentifier, profile_key): client = self.host.getClient(profile_key) return self.deleteNode( client, jid.JID(service_s) if service_s else None, nodeIdentifier ) def deleteNode(self, client, service, nodeIdentifier): return client.pubsub_client.deleteNode(service, nodeIdentifier) def _addWatch(self, service_s, node, profile_key): """watch modifications on a node This method should only be called from bridge """ client = self.host.getClient(profile_key) service = jid.JID(service_s) if service_s else client.jid.userhostJID() client.pubsub_watching.add((service, node)) def _removeWatch(self, service_s, node, profile_key): """remove a node watch This method should only be called from bridge """ client = self.host.getClient(profile_key) service = jid.JID(service_s) if service_s else client.jid.userhostJID() client.pubsub_watching.remove((service, node)) def _retractItem( self, service_s, nodeIdentifier, itemIdentifier, notify, profile_key ): return self._retractItems( service_s, nodeIdentifier, (itemIdentifier,), notify, profile_key ) def _retractItems( self, service_s, nodeIdentifier, itemIdentifiers, notify, profile_key ): client = self.host.getClient(profile_key) return self.retractItems( client, jid.JID(service_s) if service_s else None, nodeIdentifier, itemIdentifiers, notify, ) def retractItems( self, client, service, nodeIdentifier, itemIdentifiers, notify=True, ): return client.pubsub_client.retractItems( service, nodeIdentifier, itemIdentifiers, notify=notify ) def _renameItem( self, service, node, item_id, new_id, profile_key=C.PROF_KEY_NONE, ): client = self.host.getClient(profile_key) service = jid.JID(service) if service else None return defer.ensureDeferred(self.renameItem( client, service, node, item_id, new_id )) async def renameItem( self, client: SatXMPPEntity, service: Optional[jid.JID], node: str, item_id: str, new_id: str ) -> None: """Rename an item by recreating it then deleting it we have to recreate then delete because there is currently no rename operation with PubSub """ if not item_id or not new_id: raise ValueError("item_id and new_id must not be empty") # retract must be done last, so if something goes wrong, the exception will stop # the workflow and no accidental delete should happen item_elt = (await self.getItems(client, service, node, item_ids=[item_id]))[0][0] await self.sendItem(client, service, node, item_elt.firstChildElement(), new_id) await self.retractItems(client, service, node, [item_id]) def _subscribe(self, service, nodeIdentifier, options, profile_key=C.PROF_KEY_NONE): client = self.host.getClient(profile_key) service = None if not service else jid.JID(service) d = defer.ensureDeferred( self.subscribe( client, service, nodeIdentifier, options=data_format.deserialise(options) ) ) d.addCallback(lambda subscription: subscription.subscriptionIdentifier or "") return d async def subscribe( self, client: SatXMPPEntity, service: jid.JID, nodeIdentifier: str, sub_jid: Optional[jid.JID] = None, options: Optional[dict] = None ) -> pubsub.Subscription: # TODO: reimplement a subscribtion cache, checking that we have not subscription before trying to subscribe cont, trigger_sub = await self.host.trigger.asyncReturnPoint( "XEP-0060_subscribe", client, service, nodeIdentifier, sub_jid, options, ) if not cont: return trigger_sub subscription = await client.pubsub_client.subscribe( service, nodeIdentifier, sub_jid or client.jid.userhostJID(), options=options, sender=client.jid.userhostJID() ) return subscription def _unsubscribe(self, service, nodeIdentifier, profile_key=C.PROF_KEY_NONE): client = self.host.getClient(profile_key) service = None if not service else jid.JID(service) return defer.ensureDeferred(self.unsubscribe(client, service, nodeIdentifier)) async def unsubscribe( self, client: SatXMPPEntity, service: jid.JID, nodeIdentifier: str, sub_jid: Optional[jid.JID] = None, subscriptionIdentifier: Optional[str] = None, sender: Optional[jid.JID] = None, ) -> None: if not await self.host.trigger.asyncPoint( "XEP-0060_unsubscribe", client, service, nodeIdentifier, sub_jid, subscriptionIdentifier, sender ): return try: await client.pubsub_client.unsubscribe( service, nodeIdentifier, sub_jid or client.jid.userhostJID(), subscriptionIdentifier, sender, ) except error.StanzaError as e: try: next(e.getElement().elements(pubsub.NS_PUBSUB_ERRORS, "not-subscribed")) except StopIteration: raise e else: log.info( f"{sender.full() if sender else client.jid.full()} was not " f"subscribed to node {nodeIdentifier!s} at {service.full()}" ) @utils.ensure_deferred async def _subscriptions( self, service="", nodeIdentifier="", profile_key=C.PROF_KEY_NONE ) -> str: client = self.host.getClient(profile_key) service = None if not service else jid.JID(service) subs = await self.subscriptions(client, service, nodeIdentifier or None) return data_format.serialise(subs) async def subscriptions( self, client: SatXMPPEntity, service: Optional[jid.JID] = None, node: Optional[str] = None ) -> List[Dict[str, Union[str, bool]]]: """Retrieve subscriptions from a service @param service(jid.JID): PubSub service @param nodeIdentifier(unicode, None): node to check None to get all subscriptions """ cont, ret = await self.host.trigger.asyncReturnPoint( "XEP-0060_subscriptions", client, service, node ) if not cont: return ret subs = await client.pubsub_client.subscriptions(service, node) ret = [] for sub in subs: sub_dict = { "service": service.host if service else client.jid.host, "node": sub.nodeIdentifier, "subscriber": sub.subscriber.full(), "state": sub.state, } if sub.subscriptionIdentifier is not None: sub_dict["id"] = sub.subscriptionIdentifier ret.append(sub_dict) return ret ## misc tools ## def getNodeURI(self, service, node, item=None): """Return XMPP URI of a PubSub node @param service(jid.JID): PubSub service @param node(unicode): node @return (unicode): URI of the node """ # FIXME: deprecated, use sat.tools.common.uri instead assert service is not None # XXX: urllib.urlencode use "&" to separate value, while XMPP URL (cf. RFC 5122) # use ";" as a separator. So if more than one value is used in query_data, # urlencode MUST NOT BE USED. query_data = [("node", node.encode("utf-8"))] if item is not None: query_data.append(("item", item.encode("utf-8"))) return "xmpp:{service}?;{query}".format( service=service.userhost(), query=urllib.parse.urlencode(query_data) ) ## methods to manage several stanzas/jids at once ## # generic # def getRTResults( self, session_id, on_success=None, on_error=None, profile=C.PROF_KEY_NONE ): return self.rt_sessions.getResults(session_id, on_success, on_error, profile) def transItemsData(self, items_data, item_cb=lambda item: item.toXml()): """Helper method to transform result from [getItems] the items_data must be a tuple(list[domish.Element], dict[unicode, unicode]) as returned by [getItems]. @param items_data(tuple): tuple returned by [getItems] @param item_cb(callable): method to transform each item @return (tuple): a serialised form ready to go throught bridge """ items, metadata = items_data items = [item_cb(item) for item in items] return (items, metadata) def transItemsDataD(self, items_data, item_cb): """Helper method to transform result from [getItems], deferred version the items_data must be a tuple(list[domish.Element], dict[unicode, unicode]) as returned by [getItems]. metadata values are then casted to unicode and each item is passed to items_cb. An errback is added to item_cb, and when it is fired the value is filtered from final items @param items_data(tuple): tuple returned by [getItems] @param item_cb(callable): method to transform each item (must return a deferred) @return (tuple): a deferred which fire a dict which can be serialised to go throught bridge """ items, metadata = items_data def eb(failure_): log.warning(f"Error while parsing item: {failure_.value}") d = defer.gatherResults([item_cb(item).addErrback(eb) for item in items]) d.addCallback(lambda parsed_items: ( [i for i in parsed_items if i is not None], metadata )) return d def serDList(self, results, failure_result=None): """Serialise a DeferredList result @param results: DeferredList results @param failure_result: value to use as value for failed Deferred (default: empty tuple) @return (list): list with: - failure: empty in case of success, else error message - result """ if failure_result is None: failure_result = () return [ ("", result) if success else (str(result.result) or UNSPECIFIED, failure_result) for success, result in results ] # subscribe # @utils.ensure_deferred async def _getNodeSubscriptions( self, service: str, node: str, profile_key: str ) -> Dict[str, str]: client = self.host.getClient(profile_key) subs = await self.getNodeSubscriptions( client, jid.JID(service) if service else None, node ) return {j.full(): a for j, a in subs.items()} async def getNodeSubscriptions( self, client: SatXMPPEntity, service: Optional[jid.JID], nodeIdentifier: str ) -> Dict[jid.JID, str]: """Retrieve subscriptions to a node @param nodeIdentifier(unicode): node to get subscriptions from """ if not nodeIdentifier: raise exceptions.DataError("node identifier can't be empty") request = pubsub.PubSubRequest("subscriptionsGet") request.recipient = service request.nodeIdentifier = nodeIdentifier iq_elt = await request.send(client.xmlstream) try: subscriptions_elt = next( iq_elt.pubsub.elements((pubsub.NS_PUBSUB, "subscriptions")) ) except StopIteration: raise ValueError( _("Invalid result: missing <subscriptions> element: {}").format( iq_elt.toXml ) ) except AttributeError as e: raise ValueError(_("Invalid result: {}").format(e)) try: return { jid.JID(s["jid"]): s["subscription"] for s in subscriptions_elt.elements( (pubsub.NS_PUBSUB, "subscription") ) } except KeyError: raise ValueError( _("Invalid result: bad <subscription> element: {}").format( iq_elt.toXml ) ) def _setNodeSubscriptions( self, service_s, nodeIdentifier, subscriptions, profile_key=C.PROF_KEY_NONE ): client = self.host.getClient(profile_key) subscriptions = { jid.JID(jid_): subscription for jid_, subscription in subscriptions.items() } d = self.setNodeSubscriptions( client, jid.JID(service_s) if service_s else None, nodeIdentifier, subscriptions, ) return d def setNodeSubscriptions(self, client, service, nodeIdentifier, subscriptions): """Set or update subscriptions of a node owned by profile @param subscriptions(dict[jid.JID, unicode]): subscriptions to set check https://xmpp.org/extensions/xep-0060.html#substates for a list of possible subscriptions """ request = pubsub.PubSubRequest("subscriptionsSet") request.recipient = service request.nodeIdentifier = nodeIdentifier request.subscriptions = { pubsub.Subscription(nodeIdentifier, jid_, state) for jid_, state in subscriptions.items() } d = request.send(client.xmlstream) return d def _manySubscribeRTResult(self, session_id, profile_key=C.PROF_KEY_DEFAULT): """Get real-time results for subcribeToManu session @param session_id: id of the real-time deferred session @param return (tuple): (remaining, results) where: - remaining is the number of still expected results - results is a list of tuple(unicode, unicode, bool, unicode) with: - service: pubsub service - and node: pubsub node - failure(unicode): empty string in case of success, error message else @param profile_key: %(doc_profile_key)s """ profile = self.host.getClient(profile_key).profile d = self.rt_sessions.getResults( session_id, on_success=lambda result: "", on_error=lambda failure: str(failure.value), profile=profile, ) # we need to convert jid.JID to unicode with full() to serialise it for the bridge d.addCallback( lambda ret: ( ret[0], [ (service.full(), node, "" if success else failure or UNSPECIFIED) for (service, node), (success, failure) in ret[1].items() ], ) ) return d def _subscribeToMany( self, node_data, subscriber=None, options=None, profile_key=C.PROF_KEY_NONE ): return self.subscribeToMany( [(jid.JID(service), str(node)) for service, node in node_data], jid.JID(subscriber), options, profile_key, ) def subscribeToMany( self, node_data, subscriber, options=None, profile_key=C.PROF_KEY_NONE ): """Subscribe to several nodes at once. @param node_data (iterable[tuple]): iterable of tuple (service, node) where: - service (jid.JID) is the pubsub service - node (unicode) is the node to subscribe to @param subscriber (jid.JID): optional subscription identifier. @param options (dict): subscription options @param profile_key (str): %(doc_profile_key)s @return (str): RT Deferred session id """ client = self.host.getClient(profile_key) deferreds = {} for service, node in node_data: deferreds[(service, node)] = defer.ensureDeferred( client.pubsub_client.subscribe( service, node, subscriber, options=options ) ) return self.rt_sessions.newSession(deferreds, client.profile) # found_nodes = yield self.listNodes(service, profile=client.profile) # subscribed_nodes = yield self.listSubscribedNodes(service, profile=client.profile) # d_list = [] # for nodeIdentifier in (set(nodeIdentifiers) - set(subscribed_nodes)): # if nodeIdentifier not in found_nodes: # log.debug(u"Skip the subscription to [{node}]: node doesn't exist".format(node=nodeIdentifier)) # continue # avoid sat-pubsub "SubscriptionExists" error # d_list.append(client.pubsub_client.subscribe(service, nodeIdentifier, sub_jid or client.pubsub_client.parent.jid.userhostJID(), options=options)) # defer.returnValue(d_list) # get # def _getFromManyRTResult(self, session_id, profile_key=C.PROF_KEY_DEFAULT): """Get real-time results for getFromMany session @param session_id: id of the real-time deferred session @param profile_key: %(doc_profile_key)s @param return (tuple): (remaining, results) where: - remaining is the number of still expected results - results is a list of tuple with - service (unicode): pubsub service - node (unicode): pubsub node - failure (unicode): empty string in case of success, error message else - items (list[s]): raw XML of items - metadata(dict): serialised metadata """ profile = self.host.getClient(profile_key).profile d = self.rt_sessions.getResults( session_id, on_success=lambda result: ("", self.transItemsData(result)), on_error=lambda failure: (str(failure.value) or UNSPECIFIED, ([], {})), profile=profile, ) d.addCallback( lambda ret: ( ret[0], [ (service.full(), node, failure, items, metadata) for (service, node), (success, (failure, (items, metadata))) in ret[ 1 ].items() ], ) ) return d def _getFromMany( self, node_data, max_item=10, extra="", profile_key=C.PROF_KEY_NONE ): """ @param max_item(int): maximum number of item to get, C.NO_LIMIT for no limit """ max_item = None if max_item == C.NO_LIMIT else max_item extra = self.parseExtra(data_format.deserialise(extra)) return self.getFromMany( [(jid.JID(service), str(node)) for service, node in node_data], max_item, extra.rsm_request, extra.extra, profile_key, ) def getFromMany(self, node_data, max_item=None, rsm_request=None, extra=None, profile_key=C.PROF_KEY_NONE): """Get items from many nodes at once @param node_data (iterable[tuple]): iterable of tuple (service, node) where: - service (jid.JID) is the pubsub service - node (unicode) is the node to get items from @param max_items (int): optional limit on the number of retrieved items. @param rsm_request (RSMRequest): RSM request data @param profile_key (unicode): %(doc_profile_key)s @return (str): RT Deferred session id """ client = self.host.getClient(profile_key) deferreds = {} for service, node in node_data: deferreds[(service, node)] = defer.ensureDeferred(self.getItems( client, service, node, max_item, rsm_request=rsm_request, extra=extra )) return self.rt_sessions.newSession(deferreds, client.profile) @implementer(disco.IDisco) class SatPubSubClient(rsm.PubSubClient): def __init__(self, host, parent_plugin): self.host = host self.parent_plugin = parent_plugin rsm.PubSubClient.__init__(self) def connectionInitialized(self): rsm.PubSubClient.connectionInitialized(self) def _getNodeCallbacks(self, node, event): """Generate callbacks from given node and event @param node(unicode): node used for the item any registered node which prefix the node will match @param event(unicode): one of C.PS_ITEMS, C.PS_RETRACT, C.PS_DELETE @return (iterator[callable]): callbacks for this node/event """ for registered_node, callbacks_dict in self.parent_plugin._node_cb.items(): if not node.startswith(registered_node): continue try: for callback in callbacks_dict[event]: yield callback except KeyError: continue def itemsReceived(self, event): log.debug("Pubsub items received") for callback in self._getNodeCallbacks(event.nodeIdentifier, C.PS_ITEMS): d = utils.asDeferred(callback, self.parent, event) d.addErrback(lambda f: log.error( f"Error while running items event callback {callback}: {f}" )) client = self.parent if (event.sender, event.nodeIdentifier) in client.pubsub_watching: raw_items = [i.toXml() for i in event.items] self.host.bridge.psEventRaw( event.sender.full(), event.nodeIdentifier, C.PS_ITEMS, raw_items, client.profile, ) def deleteReceived(self, event): log.debug(("Publish node deleted")) for callback in self._getNodeCallbacks(event.nodeIdentifier, C.PS_DELETE): d = utils.asDeferred(callback, self.parent, event) d.addErrback(lambda f: log.error( f"Error while running delete event callback {callback}: {f}" )) client = self.parent if (event.sender, event.nodeIdentifier) in client.pubsub_watching: self.host.bridge.psEventRaw( event.sender.full(), event.nodeIdentifier, C.PS_DELETE, [], client.profile ) def purgeReceived(self, event): log.debug(("Publish node purged")) for callback in self._getNodeCallbacks(event.nodeIdentifier, C.PS_PURGE): d = utils.asDeferred(callback, self.parent, event) d.addErrback(lambda f: log.error( f"Error while running purge event callback {callback}: {f}" )) client = self.parent if (event.sender, event.nodeIdentifier) in client.pubsub_watching: self.host.bridge.psEventRaw( event.sender.full(), event.nodeIdentifier, C.PS_PURGE, [], client.profile ) def subscriptions(self, service, nodeIdentifier, sender=None): """Return the list of subscriptions to the given service and node. @param service: The publish subscribe service to retrieve the subscriptions from. @type service: L{JID<twisted.words.protocols.jabber.jid.JID>} @param nodeIdentifier: The identifier of the node (leave empty to retrieve all subscriptions). @type nodeIdentifier: C{unicode} @return (list[pubsub.Subscription]): list of subscriptions """ request = pubsub.PubSubRequest("subscriptions") request.recipient = service request.nodeIdentifier = nodeIdentifier request.sender = sender d = request.send(self.xmlstream) def cb(iq): subs = [] for subscription_elt in iq.pubsub.subscriptions.elements( pubsub.NS_PUBSUB, "subscription" ): subscription = pubsub.Subscription( subscription_elt["node"], jid.JID(subscription_elt["jid"]), subscription_elt["subscription"], subscriptionIdentifier=subscription_elt.getAttribute("subid"), ) subs.append(subscription) return subs return d.addCallback(cb) def purgeNode(self, service, nodeIdentifier): """Purge a node (i.e. delete all items from it) @param service(jid.JID, None): service to send the item to None to use PEP @param NodeIdentifier(unicode): PubSub node to use """ # TODO: propose this upstream and remove it once merged request = pubsub.PubSubRequest('purge') request.recipient = service request.nodeIdentifier = nodeIdentifier return request.send(self.xmlstream) def getDiscoInfo(self, requestor, service, nodeIdentifier=""): disco_info = [] self.host.trigger.point("PubSub Disco Info", disco_info, self.parent.profile) return disco_info def getDiscoItems(self, requestor, service, nodeIdentifier=""): return []