added plugin xep-0115: entity capabilities

src/plugins/plugin_xep_0115.py

@@ -0,0 +1,201 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+"""
+SAT plugin for managing xep-0115
+Copyright (C) 2009, 2010, 2011  Jérôme Poisson (goffi@goffi.org)
+
+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 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+from logging import debug, info, error, warning
+from twisted.words.xish import domish
+from twisted.words.protocols.jabber import client, jid, xmlstream
+from twisted.words.protocols.jabber import error as jab_error
+from twisted.words.protocols.jabber.xmlstream import IQ
+import os.path
+import types
+
+from zope.interface import implements
+
+from wokkel import disco, iwokkel
+
+from hashlib import sha1
+from base64 import b64encode
+
+try:
+    from twisted.words.protocols.xmlstream import XMPPHandler
+except ImportError:
+    from wokkel.subprotocols import XMPPHandler
+
+PRESENCE = '/presence'
+NS_ENTITY_CAPABILITY = 'http://jabber.org/protocol/caps'
+CAPABILITY_UPDATE = PRESENCE + '/c[@xmlns="' +  NS_ENTITY_CAPABILITY + '"]'
+
+PLUGIN_INFO = {
+"name": "XEP 0115 Plugin",
+"import_name": "XEP_0115",
+"type": "XEP",
+"protocols": ["XEP-0115"],
+"dependencies": [],
+"main": "XEP_0115",
+"handler": "yes",
+"description": _("""Implementation of entity capabilities""")
+}
+
+class HashGenerationError(Exception):
+    pass
+
+class ByteIdentity(object):
+    """This class manage identity as bytes (needed for i;octet sort),
+    it is used for the hash generation"""
+
+    def __init__(self, identity, lang=None):
+        assert isinstance(identity, disco.DiscoIdentity)
+        self.category = identity.category.encode('utf-8')
+        self.idType = identity.type.encode('utf-8')
+        self.name = identity.name.encode('utf-8') if identity.name else ''
+        self.lang = lang.encode('utf-8') if lang else ''
+
+    def __str__(self):
+        return "%s/%s/%s/%s" % (self.category, self.idType, self.lang, self.name)
+           
+
+class XEP_0115():
+    cap_hash = None
+
+    def __init__(self, host):
+        info(_("Plugin XEP_0115 initialization"))
+        self.host = host
+        host.trigger.add("Disco Handled", self.checkHash)
+        self.hash_cache = host.memory.getPrivate("entity_capabilities_cache") or {}  #key = hash or jid
+        self.jid_hash = {} #jid to hash mapping, map to a discoInfo if the hash method is unknown 
+
+    def checkHash(self, profile):
+        if not XEP_0115.cap_hash:
+            XEP_0115.cap_hash = self.generateHash(profile)
+        else:
+            self.presenceHack(profile)
+        return True
+        
+    def getHandler(self, profile):
+        return XEP_0115_handler(self, profile)
+
+    def presenceHack(self, profile):
+        """modify SatPresenceProtocol to add capabilities data"""
+        client=self.host.getClient(profile)
+        presenceInst = client.presence
+        def hacked_send(self, obj):
+            obj.addChild(self._c_elt)
+            self._legacy_send(obj)
+        new_send = types.MethodType(hacked_send, presenceInst, presenceInst.__class__)
+        presenceInst._legacy_send = presenceInst.send
+        presenceInst.send = new_send
+        c_elt = domish.Element((NS_ENTITY_CAPABILITY,'c'))
+        c_elt['hash']='sha-1'
+        c_elt['node']='http://wiki.goffi.org/wiki/Salut_%C3%A0_Toi'
+        c_elt['ver']=XEP_0115.cap_hash
+        presenceInst._c_elt = c_elt
+
+
+    def generateHash(self, profile_key="@DEFAULT@"):
+        """This method generate a sha1 hash as explained in xep-0115 #5.1
+        it then store it in XEP_0115.cap_hash"""
+        profile = self.host.memory.getProfileName(profile_key)
+        if not profile:
+            error ('Requesting hash for an inexistant profile')
+            raise HashGenerationError
+
+        client = self.host.getClient(profile_key)
+        if not client:
+            error ('Requesting hash for an inexistant client')
+            raise HashGenerationError
+        
+        def generateHash_2(services, profile):
+            _s=[]
+            byte_identities = [ByteIdentity(identity) for identity in filter(lambda x:isinstance(x,disco.DiscoIdentity),services)] #FIXME: lang must be managed here
+            byte_identities.sort(key=lambda i:i.lang)
+            byte_identities.sort(key=lambda i:i.idType)
+            byte_identities.sort(key=lambda i:i.category)
+            for identity in byte_identities:
+                _s.append(str(identity))
+                _s.append('<')
+            byte_features = [feature.encode('utf-8') for feature in filter(lambda x:isinstance(x,disco.DiscoFeature),services)]
+            byte_features.sort() #XXX: the default sort has the same behaviour as the requested RFC 4790 i;octet sort
+            for feature in byte_features:
+                _s.append(feature)
+                _s.append('<')
+            #TODO: manage XEP-0128 data form here
+            XEP_0115.cap_hash = b64encode(sha1(''.join(_s)).digest())
+            debug(_('Capability hash generated: [%s]') % XEP_0115.cap_hash)
+            self.presenceHack(profile)
+            
+        services = client.discoHandler.info(client.jid, client.jid, '').addCallback(generateHash_2, profile)
+   
+class XEP_0115_handler(XMPPHandler):
+    implements(iwokkel.IDisco)
+   
+    def __init__(self, plugin_parent, profile):
+        self.plugin_parent = plugin_parent
+        self.host = plugin_parent.host
+        self.profile = profile
+
+    def connectionInitialized(self):
+        self.xmlstream.addObserver(CAPABILITY_UPDATE, self.update)
+    
+    def getDiscoInfo(self, requestor, target, nodeIdentifier=''):
+        return [disco.DiscoFeature(NS_ENTITY_CAPABILITY)]
+
+    def getDiscoItems(self, requestor, target, nodeIdentifier=''):
+        return []
+
+    def _updateCache(self, discoResult, from_jid, key):
+        """Actually update the cache
+        @param discoResult: result of the requestInfo
+        @param known_hash: True if it's a hash method we know, we don't save the cache else"""
+        if key:
+            self.plugin_parent.jid_hash[from_jid] = key
+            self.plugin_parent.hash_cache[key] = discoResult
+        else:
+            #No key, that mean unknown hash method
+            self.plugin_parent.jid_hash[from_jid] = discoResult
+        self.host.memory.setPrivate("entity_capabilities_cache", self.plugin_parent.hash_cache)
+
+
+    def update(self, presence):
+        """
+        Manage the capabilities of the entity
+        Check if we know the version of this capatilities
+        and get the capibilities if necessary
+        """
+        from_jid = jid.JID(presence['from'])
+        c_elem = filter (lambda x:x.name == "c", presence.elements())[0] #We only want the "c" element
+        try:
+            ver=c_elem['ver']
+            hash=c_elem['hash']
+            node=c_elem['node']
+        except KeyError:
+            warning('Received invalid capabilities tag')
+            return
+        if not self.plugin_parent.jid_hash.has_key(from_jid):
+            if self.plugin_parent.hash_cache.has_key(ver):
+                #we know that hash, we just link it with the jid
+                self.plugin_parent.jid_hash[from_jid] = ver
+            else:
+                if hash!='sha-1':
+                    #unknown hash method
+                    warning('Unknown hash for entity capabilities: [%s]' % hash)
+                self.parent.disco.requestInfo(from_jid).addCallback(self._updateCache, from_jid, ver if hash=='sha-1' else None )
+        #TODO: me must manage the full algorithm described at XEP-0115 #5.4 part 3
+