## dispatcher_nb.py ## based on dispatcher.py ## ## Copyright (C) 2003-2005 Alexey "Snake" Nezhdanov ## modified by Dimitur Kirov ## ## This program is free software; you can redistribute it and/or modify ## it under the terms of the GNU General Public License as published by ## the Free Software Foundation; either version 2, 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 General Public License for more details. """ Main xmpp decision making logic. Provides library with methods to assign different handlers to different XMPP stanzas and namespaces """ import simplexml, sys, locale from xml.parsers.expat import ExpatError from plugin import PlugIn from protocol import (NS_STREAMS, NS_XMPP_STREAMS, NS_HTTP_BIND, Iq, Presence, Message, Protocol, Node, Error, ERR_FEATURE_NOT_IMPLEMENTED, StreamError) import logging log = logging.getLogger('gajim.c.x.dispatcher_nb') #: default timeout to wait for response for our id DEFAULT_TIMEOUT_SECONDS = 25 outgoingID = 0 XML_DECLARATION = '' # FIXME: ugly class Dispatcher(): """ Why is this here - I needed to redefine Dispatcher for BOSH and easiest way was to inherit original Dispatcher (now renamed to XMPPDispatcher). Trouble is that reference used to access dispatcher instance is in Client attribute named by __class__.__name__ of the dispatcher instance .. long story short: I wrote following to avoid changing each client.Dispatcher.whatever() in xmpp If having two kinds of dispatcher will go well, I will rewrite the dispatcher references in other scripts """ def PlugIn(self, client_obj, after_SASL=False, old_features=None): if client_obj.protocol_type == 'XMPP': XMPPDispatcher().PlugIn(client_obj) elif client_obj.protocol_type == 'BOSH': BOSHDispatcher().PlugIn(client_obj, after_SASL, old_features) else: assert False # should never be reached @classmethod def get_instance(cls, *args, **kwargs): """ Factory Method for object creation Use this instead of directly initializing the class in order to make unit testing much easier. """ return cls(*args, **kwargs) class XMPPDispatcher(PlugIn): """ Handles XMPP stream and is the first who takes control over a fresh stanza Is plugged into NonBlockingClient but can be replugged to restart handled stream headers (used by SASL f.e.). """ def __init__(self): PlugIn.__init__(self) self.handlers = {} self._expected = {} self._defaultHandler = None self._pendingExceptions = [] self._eventHandler = None self._cycleHandlers = [] self._exported_methods=[self.RegisterHandler, self.RegisterDefaultHandler, self.RegisterEventHandler, self.UnregisterCycleHandler, self.RegisterCycleHandler, self.RegisterHandlerOnce, self.UnregisterHandler, self.RegisterProtocol, self.SendAndWaitForResponse, self.SendAndCallForResponse, self.getAnID, self.Event, self.send] # Let the dispatcher know if there is support for stream management self.sm = None def getAnID(self): global outgoingID outgoingID += 1 return repr(outgoingID) def dumpHandlers(self): """ Return set of user-registered callbacks in it's internal format. Used within the library to carry user handlers set over Dispatcher replugins """ return self.handlers def restoreHandlers(self, handlers): """ Restore user-registered callbacks structure from dump previously obtained via dumpHandlers. Used within the library to carry user handlers set over Dispatcher replugins. """ self.handlers = handlers def _init(self): """ Register default namespaces/protocols/handlers. Used internally """ # FIXME: inject dependencies, do not rely that they are defined by our # owner self.RegisterNamespace('unknown') self.RegisterNamespace(NS_STREAMS) self.RegisterNamespace(self._owner.defaultNamespace) self.RegisterProtocol('iq', Iq) self.RegisterProtocol('presence', Presence) self.RegisterProtocol('message', Message) self.RegisterDefaultHandler(self.returnStanzaHandler) self.RegisterEventHandler(self._owner._caller._event_dispatcher) self.on_responses = {} def plugin(self, owner): """ Plug the Dispatcher instance into Client class instance and send initial stream header. Used internally """ self._init() self._owner.lastErrNode = None self._owner.lastErr = None self._owner.lastErrCode = None if hasattr(self._owner, 'StreamInit'): self._owner.StreamInit() else: self.StreamInit() def plugout(self): """ Prepare instance to be destructed """ self.Stream.dispatch = None self.Stream.features = None self.Stream.destroy() self._owner = None self.Stream = None def StreamInit(self): """ Send an initial stream header """ self._owner.Connection.sendqueue = [] self.Stream = simplexml.NodeBuilder() self.Stream.dispatch = self.dispatch self.Stream._dispatch_depth = 2 self.Stream.stream_header_received = self._check_stream_start self.Stream.features = None self._metastream = Node('stream:stream') self._metastream.setNamespace(self._owner.Namespace) self._metastream.setAttr('version', '1.0') self._metastream.setAttr('xmlns:stream', NS_STREAMS) self._metastream.setAttr('to', self._owner.Server) if locale.getdefaultlocale()[0]: self._metastream.setAttr('xml:lang', locale.getdefaultlocale()[0].split('_')[0]) self._owner.send("%s%s>" % (XML_DECLARATION, str(self._metastream)[:-2])) def _check_stream_start(self, ns, tag, attrs): if ns != NS_STREAMS or tag!='stream': raise ValueError('Incorrect stream start: (%s,%s). Terminating.' % (tag, ns)) def ProcessNonBlocking(self, data): """ Check incoming stream for data waiting :param data: data received from transports/IO sockets :return: 1) length of processed data if some data were processed; 2) '0' string if no data were processed but link is alive; 3) 0 (zero) if underlying connection is closed. """ # FIXME: # When an error occurs we disconnect the transport directly. Client's # disconnect method will never be called. # Is this intended? # also look at transports start_disconnect() for handler in self._cycleHandlers: handler(self) if len(self._pendingExceptions) > 0: _pendingException = self._pendingExceptions.pop() raise _pendingException[0], _pendingException[1], _pendingException[2] try: self.Stream.Parse(data) # end stream:stream tag received if self.Stream and self.Stream.has_received_endtag(): self._owner.disconnect(self.Stream.streamError) return 0 except ExpatError: log.error('Invalid XML received from server. Forcing disconnect.') self._owner.Connection.disconnect() return 0 except ValueError, e: log.debug('ValueError: %s' % str(e)) self._owner.Connection.pollend() return 0 if len(self._pendingExceptions) > 0: _pendingException = self._pendingExceptions.pop() raise _pendingException[0], _pendingException[1], _pendingException[2] if len(data) == 0: return '0' return len(data) def RegisterNamespace(self, xmlns, order='info'): """ Create internal structures for newly registered namespace You can register handlers for this namespace afterwards. By default one namespace is already registered (jabber:client or jabber:component:accept depending on context. """ log.debug('Registering namespace "%s"' % xmlns) self.handlers[xmlns] = {} self.RegisterProtocol('unknown', Protocol, xmlns=xmlns) self.RegisterProtocol('default', Protocol, xmlns=xmlns) def RegisterProtocol(self, tag_name, Proto, xmlns=None, order='info'): """ Used to declare some top-level stanza name to dispatcher Needed to start registering handlers for such stanzas. Iq, message and presence protocols are registered by default. """ if not xmlns: xmlns=self._owner.defaultNamespace log.debug('Registering protocol "%s" as %s(%s)' %(tag_name, Proto, xmlns)) self.handlers[xmlns][tag_name] = {type:Proto, 'default':[]} def RegisterNamespaceHandler(self, xmlns, handler, typ='', ns='', makefirst=0, system=0): """ Register handler for processing all stanzas for specified namespace """ self.RegisterHandler('default', handler, typ, ns, xmlns, makefirst, system) def RegisterHandler(self, name, handler, typ='', ns='', xmlns=None, makefirst=False, system=False): """ Register user callback as stanzas handler of declared type Callback arguments: dispatcher instance (for replying), incoming return of previous handlers. The callback must raise xmpp.NodeProcessed just before return if it wants to prevent other callbacks to be called with the same stanza as argument _and_, more importantly library from returning stanza to sender with error set. :param name: name of stanza. F.e. "iq". :param handler: user callback. :param typ: value of stanza's "type" attribute. If not specified any value will match :param ns: namespace of child that stanza must contain. :param makefirst: insert handler in the beginning of handlers list instead of adding it to the end. Note that more common handlers i.e. w/o "typ" and " will be called first nevertheless. :param system: call handler even if NodeProcessed Exception were raised already. """ if not xmlns: xmlns=self._owner.defaultNamespace log.debug('Registering handler %s for "%s" type->%s ns->%s(%s)' % (handler, name, typ, ns, xmlns)) if not typ and not ns: typ='default' if xmlns not in self.handlers: self.RegisterNamespace(xmlns, 'warn') if name not in self.handlers[xmlns]: self.RegisterProtocol(name, Protocol, xmlns, 'warn') if typ+ns not in self.handlers[xmlns][name]: self.handlers[xmlns][name][typ+ns]=[] if makefirst: self.handlers[xmlns][name][typ+ns].insert(0, {'func':handler, 'system':system}) else: self.handlers[xmlns][name][typ+ns].append({'func':handler, 'system':system}) def RegisterHandlerOnce(self, name, handler, typ='', ns='', xmlns=None, makefirst=0, system=0): """ Unregister handler after first call (not implemented yet) """ # FIXME Drop or implement if not xmlns: xmlns = self._owner.defaultNamespace self.RegisterHandler(name, handler, typ, ns, xmlns, makefirst, system) def UnregisterHandler(self, name, handler, typ='', ns='', xmlns=None): """ Unregister handler. "typ" and "ns" must be specified exactly the same as with registering. """ if not xmlns: xmlns = self._owner.defaultNamespace if not typ and not ns: typ='default' if xmlns not in self.handlers: return if name not in self.handlers[xmlns]: return if typ+ns not in self.handlers[xmlns][name]: return for pack in self.handlers[xmlns][name][typ+ns]: if pack['func'] == handler: try: self.handlers[xmlns][name][typ+ns].remove(pack) except ValueError: pass def RegisterDefaultHandler(self, handler): """ Specify the handler that will be used if no NodeProcessed exception were raised. This is returnStanzaHandler by default. """ self._defaultHandler = handler def RegisterEventHandler(self, handler): """ Register handler that will process events. F.e. "FILERECEIVED" event. See common/connection: _event_dispatcher() """ self._eventHandler = handler def returnStanzaHandler(self, conn, stanza): """ Return stanza back to the sender with error set """ if stanza.getType() in ('get', 'set'): conn._owner.send(Error(stanza, ERR_FEATURE_NOT_IMPLEMENTED)) def RegisterCycleHandler(self, handler): """ Register handler that will be called on every Dispatcher.Process() call """ if handler not in self._cycleHandlers: self._cycleHandlers.append(handler) def UnregisterCycleHandler(self, handler): """ Unregister handler that will is called on every Dispatcher.Process() call """ if handler in self._cycleHandlers: self._cycleHandlers.remove(handler) def Event(self, realm, event, data): """ Raise some event :param realm: scope of event. Usually a namespace. :param event: the event itself. F.e. "SUCCESSFUL SEND". :param data: data that comes along with event. Depends on event. """ if self._eventHandler: self._eventHandler(realm, event, data) else: log.warning('Received unhandled event: %s' % event) def dispatch(self, stanza, session=None, direct=0): """ Main procedure that performs XMPP stanza recognition and calling apppropriate handlers for it. Called by simplexml """ # FIXME: Where do we set session and direct. Why? What are those intended # to do? #log.info('dispatch called: stanza = %s, session = %s, direct= %s' # % (stanza, session, direct)) if not session: session = self session.Stream._mini_dom = None name = stanza.getName() if name == 'features': self._owner.got_features = True session.Stream.features = stanza xmlns = stanza.getNamespace() # log.info('in dispatch, getting ns for %s, and the ns is %s' # % (stanza, xmlns)) if xmlns not in self.handlers: log.warn("Unknown namespace: " + xmlns) xmlns = 'unknown' # features stanza has been handled before if name not in self.handlers[xmlns]: if name != 'features': log.warn("Unknown stanza: " + name) else: log.debug("Got %s/%s stanza" % (xmlns, name)) name='unknown' else: log.debug("Got %s/%s stanza" % (xmlns, name)) if stanza.__class__.__name__ == 'Node': # FIXME: this cannot work stanza=self.handlers[xmlns][name][type](node=stanza) typ = stanza.getType() if not typ: typ = '' stanza.props = stanza.getProperties() ID = stanza.getID() # If server supports stream management if self.sm and self.sm.enabled and (stanza.getName() != 'r' and stanza.getName() != 'a' and stanza.getName() != 'enabled' and stanza.getName() != 'resumed'): # increments the number of stanzas that has been handled self.sm.in_h = self.sm.in_h + 1 list_ = ['default'] # we will use all handlers: if typ in self.handlers[xmlns][name]: list_.append(typ) # from very common... for prop in stanza.props: if prop in self.handlers[xmlns][name]: list_.append(prop) if typ and typ+prop in self.handlers[xmlns][name]: list_.append(typ+prop) # ...to very particular chain = self.handlers[xmlns]['default']['default'] for key in list_: if key: chain = chain + self.handlers[xmlns][name][key] if ID in session._expected: user = 0 if isinstance(session._expected[ID], tuple): cb, args = session._expected[ID] log.debug("Expected stanza arrived. Callback %s(%s) found!" % (cb, args)) try: cb(session,stanza,**args) except Exception, typ: if typ.__class__.__name__ != 'NodeProcessed': raise else: log.debug("Expected stanza arrived!") session._expected[ID] = stanza else: user = 1 for handler in chain: if user or handler['system']: try: handler['func'](session, stanza) except Exception, typ: if typ.__class__.__name__ != 'NodeProcessed': self._pendingExceptions.insert(0, sys.exc_info()) return user=0 if user and self._defaultHandler: self._defaultHandler(session, stanza) def _WaitForData(self, data): """ Internal wrapper around ProcessNonBlocking. Will check for """ if data is None: return res = self.ProcessNonBlocking(data) # 0 result indicates that we have closed the connection, e.g. # we have released dispatcher, so self._owner has no methods if not res: return for (_id, _iq) in self._expected.items(): if _iq is None: # If the expected Stanza would have arrived, ProcessNonBlocking # would have placed the reply stanza in there continue if _id in self.on_responses: if len(self._expected) == 1: self._owner.onreceive(None) resp, args = self.on_responses[_id] del self.on_responses[_id] if args is None: resp(_iq) else: resp(self._owner, _iq, **args) del self._expected[_id] def SendAndWaitForResponse(self, stanza, timeout=None, func=None, args=None): """ Send stanza and wait for recipient's response to it. Will call transports on_timeout callback if response is not retrieved in time Be aware: Only timeout of latest call of SendAndWait is active. """ if timeout is None: timeout = DEFAULT_TIMEOUT_SECONDS _waitid = self.send(stanza) if func: self.on_responses[_waitid] = (func, args) if timeout: self._owner.set_timeout(timeout) self._owner.onreceive(self._WaitForData) self._expected[_waitid] = None return _waitid def SendAndCallForResponse(self, stanza, func=None, args=None): """ Put stanza on the wire and call back when recipient replies. Additional callback arguments can be specified in args """ self.SendAndWaitForResponse(stanza, 0, func, args) def send(self, stanza, now=False): """ Wrap transports send method when plugged into NonBlockingClient. Makes sure stanzas get ID and from tag. """ ID = None if type(stanza) not in [type(''), type(u'')]: if isinstance(stanza, Protocol): ID = stanza.getID() if ID is None: stanza.setID(self.getAnID()) ID = stanza.getID() if self._owner._registered_name and not stanza.getAttr('from'): stanza.setAttr('from', self._owner._registered_name) # If no ID then it is a whitespace if self.sm and self.sm.enabled and ID: self.sm.uqueue.append(stanza) self.sm.out_h = self.sm.out_h + 1 if len(self.sm.uqueue) > self.sm.max_queue: self.sm.request_ack() self._owner.Connection.send(stanza, now) return ID class BOSHDispatcher(XMPPDispatcher): def PlugIn(self, owner, after_SASL=False, old_features=None): self.old_features = old_features self.after_SASL = after_SASL XMPPDispatcher.PlugIn(self, owner) def StreamInit(self): """ Send an initial stream header """ self.Stream = simplexml.NodeBuilder() self.Stream.dispatch = self.dispatch self.Stream._dispatch_depth = 2 self.Stream.stream_header_received = self._check_stream_start self.Stream.features = self.old_features self._metastream = Node('stream:stream') self._metastream.setNamespace(self._owner.Namespace) self._metastream.setAttr('version', '1.0') self._metastream.setAttr('xmlns:stream', NS_STREAMS) self._metastream.setAttr('to', self._owner.Server) if locale.getdefaultlocale()[0]: self._metastream.setAttr('xml:lang', locale.getdefaultlocale()[0].split('_')[0]) self.restart = True self._owner.Connection.send_init(after_SASL=self.after_SASL) def StreamTerminate(self): """ Send a stream terminator """ self._owner.Connection.send_terminator() def ProcessNonBlocking(self, data=None): if self.restart: fromstream = self._metastream fromstream.setAttr('from', fromstream.getAttr('to')) fromstream.delAttr('to') data = '%s%s>%s' % (XML_DECLARATION, str(fromstream)[:-2], data) self.restart = False return XMPPDispatcher.ProcessNonBlocking(self, data) def dispatch(self, stanza, session=None, direct=0): if stanza.getName() == 'body' and stanza.getNamespace() == NS_HTTP_BIND: stanza_attrs = stanza.getAttrs() if 'authid' in stanza_attrs: # should be only in init response # auth module expects id of stream in document attributes self.Stream._document_attrs['id'] = stanza_attrs['authid'] self._owner.Connection.handle_body_attrs(stanza_attrs) children = stanza.getChildren() if children: for child in children: # if child doesn't have any ns specified, simplexml (or expat) # thinks it's of parent's (BOSH body) namespace, so we have to # rewrite it to jabber:client if child.getNamespace() == NS_HTTP_BIND: child.setNamespace(self._owner.defaultNamespace) XMPPDispatcher.dispatch(self, child, session, direct) else: XMPPDispatcher.dispatch(self, stanza, session, direct)