From 78bd21b7cfe34f2183d052a292df01f1d3ad9269 Mon Sep 17 00:00:00 2001
From: Lance Stout <lancestout@gmail.com>
Date: Mon, 11 Feb 2013 18:08:34 -0800
Subject: Support using messages for IBB data transfer.
---
sleekxmpp/plugins/xep_0047/ibb.py | 20 ++++++++++-----
sleekxmpp/plugins/xep_0047/stream.py | 47 ++++++++++++++++++++++++------------
2 files changed, 45 insertions(+), 22 deletions(-)
diff --git a/sleekxmpp/plugins/xep_0047/ibb.py b/sleekxmpp/plugins/xep_0047/ibb.py
index fb48a9b9..e341433f 100644
--- a/sleekxmpp/plugins/xep_0047/ibb.py
+++ b/sleekxmpp/plugins/xep_0047/ibb.py
@@ -36,6 +36,7 @@ class XEP_0047(BasePlugin):
register_stanza_plugin(Iq, Open)
register_stanza_plugin(Iq, Close)
register_stanza_plugin(Iq, Data)
+ register_stanza_plugin(Message, Data)
self.xmpp.register_handler(Callback(
'IBB Open',
@@ -52,10 +53,16 @@ class XEP_0047(BasePlugin):
StanzaPath('iq@type=set/ibb_data'),
self._handle_data))
+ self.xmpp.register_handler(Callback(
+ 'IBB Message Data',
+ StanzaPath('message/ibb_data'),
+ self._handle_data))
+
def plugin_end(self):
self.xmpp.remove_handler('IBB Open')
self.xmpp.remove_handler('IBB Close')
self.xmpp.remove_handler('IBB Data')
+ self.xmpp.remove_handler('IBB Message Data')
self.xmpp['xep_0030'].del_feature(feature='http://jabber.org/protocol/ibb')
def session_bind(self, jid):
@@ -69,7 +76,7 @@ class XEP_0047(BasePlugin):
return True
return False
- def open_stream(self, jid, block_size=4096, sid=None, window=1,
+ def open_stream(self, jid, block_size=4096, sid=None, window=1, use_messages=False,
ifrom=None, block=True, timeout=None, callback=None):
if sid is None:
sid = str(uuid.uuid4())
@@ -83,7 +90,8 @@ class XEP_0047(BasePlugin):
iq['ibb_open']['stanza'] = 'iq'
stream = IBBytestream(self.xmpp, sid, block_size,
- iq['to'], iq['from'], window)
+ iq['to'], iq['from'], window,
+ use_messages)
with self._stream_lock:
self.pending_streams[iq['id']] = stream
@@ -139,11 +147,11 @@ class XEP_0047(BasePlugin):
self.xmpp.event('ibb_stream_start', stream)
- def _handle_data(self, iq):
- sid = iq['ibb_data']['sid']
+ def _handle_data(self, stanza):
+ sid = stanza['ibb_data']['sid']
stream = self.streams.get(sid, None)
- if stream is not None and iq['from'] != stream.sender:
- stream._recv_data(iq)
+ if stream is not None and stanza['from'] != stream.sender:
+ stream._recv_data(stanza)
else:
raise XMPPError('item-not-found')
diff --git a/sleekxmpp/plugins/xep_0047/stream.py b/sleekxmpp/plugins/xep_0047/stream.py
index b49a077b..adc86450 100644
--- a/sleekxmpp/plugins/xep_0047/stream.py
+++ b/sleekxmpp/plugins/xep_0047/stream.py
@@ -2,6 +2,7 @@ import socket
import threading
import logging
+from sleekxmpp.stanza import Iq
from sleekxmpp.util import Queue
from sleekxmpp.exceptions import XMPPError
@@ -11,11 +12,12 @@ log = logging.getLogger(__name__)
class IBBytestream(object):
- def __init__(self, xmpp, sid, block_size, to, ifrom, window_size=1):
+ def __init__(self, xmpp, sid, block_size, to, ifrom, window_size=1, use_messages=False):
self.xmpp = xmpp
self.sid = sid
self.block_size = block_size
self.window_size = window_size
+ self.use_messages = use_messages
self.receiver = to
self.sender = ifrom
@@ -46,16 +48,27 @@ class IBBytestream(object):
with self._send_seq_lock:
self.send_seq = (self.send_seq + 1) % 65535
seq = self.send_seq
- iq = self.xmpp.Iq()
- iq['type'] = 'set'
- iq['to'] = self.receiver
- iq['from'] = self.sender
- iq['ibb_data']['sid'] = self.sid
- iq['ibb_data']['seq'] = seq
- iq['ibb_data']['data'] = data
- self.window_empty.clear()
- self.window_ids.add(iq['id'])
- iq.send(block=False, callback=self._recv_ack)
+ if self.use_messages:
+ msg = self.xmpp.Message()
+ msg['to'] = self.receiver
+ msg['from'] = self.sender
+ msg['id'] = self.xmpp.new_id()
+ msg['ibb_data']['sid'] = self.sid
+ msg['ibb_data']['seq'] = seq
+ msg['ibb_data']['data'] = data
+ msg.send()
+ self.send_window.release()
+ else:
+ iq = self.xmpp.Iq()
+ iq['type'] = 'set'
+ iq['to'] = self.receiver
+ iq['from'] = self.sender
+ iq['ibb_data']['sid'] = self.sid
+ iq['ibb_data']['seq'] = seq
+ iq['ibb_data']['data'] = data
+ self.window_empty.clear()
+ self.window_ids.add(iq['id'])
+ iq.send(block=False, callback=self._recv_ack)
return len(data)
def sendall(self, data):
@@ -71,23 +84,25 @@ class IBBytestream(object):
if iq['type'] == 'error':
self.close()
- def _recv_data(self, iq):
+ def _recv_data(self, stanza):
with self._recv_seq_lock:
- new_seq = iq['ibb_data']['seq']
+ new_seq = stanza['ibb_data']['seq']
if new_seq != (self.recv_seq + 1) % 65535:
self.close()
raise XMPPError('unexpected-request')
self.recv_seq = new_seq
- data = iq['ibb_data']['data']
+ data = stanza['ibb_data']['data']
if len(data) > self.block_size:
self.close()
raise XMPPError('not-acceptable')
self.recv_queue.put(data)
self.xmpp.event('ibb_stream_data', {'stream': self, 'data': data})
- iq.reply()
- iq.send()
+
+ if isinstance(stanza, Iq):
+ stanza.reply()
+ stanza.send()
def recv(self, *args, **kwargs):
return self.read(block=True)
--
cgit v1.2.3
From fbf79755d72e35b365729d6f7e7d85fdadfb1403 Mon Sep 17 00:00:00 2001
From: Lance Stout <lancestout@gmail.com>
Date: Mon, 11 Feb 2013 19:49:38 -0800
Subject: Track which verstrings are being checked, so we don't request
duplicates.
---
sleekxmpp/plugins/xep_0115/caps.py | 50 +++++++++++++++++++++-----------------
1 file changed, 28 insertions(+), 22 deletions(-)
diff --git a/sleekxmpp/plugins/xep_0115/caps.py b/sleekxmpp/plugins/xep_0115/caps.py
index 8bad1410..1d8d9e42 100644
--- a/sleekxmpp/plugins/xep_0115/caps.py
+++ b/sleekxmpp/plugins/xep_0115/caps.py
@@ -9,8 +9,9 @@
import logging
import hashlib
import base64
+import threading
-import sleekxmpp
+from sleekxmpp import __version__
from sleekxmpp.stanza import StreamFeatures, Presence, Iq
from sleekxmpp.xmlstream import register_stanza_plugin, JID
from sleekxmpp.xmlstream.handler import Callback
@@ -45,8 +46,7 @@ class XEP_0115(BasePlugin):
'md5': hashlib.md5}
if self.caps_node is None:
- ver = sleekxmpp.__version__
- self.caps_node = 'http://sleekxmpp.com/ver/%s' % ver
+ self.caps_node = 'http://sleekxmpp.com/ver/%s' % __version__
register_stanza_plugin(Presence, stanza.Capabilities)
register_stanza_plugin(StreamFeatures, stanza.Capabilities)
@@ -90,6 +90,9 @@ class XEP_0115(BasePlugin):
disco.assign_verstring = self.assign_verstring
disco.get_verstring = self.get_verstring
+ self._processing_lock = threading.Lock()
+ self._processing = set()
+
def plugin_end(self):
self.xmpp['xep_0030'].del_feature(feature=stanza.Capabilities.namespace)
self.xmpp.del_filter('out', self._filter_add_caps)
@@ -139,13 +142,15 @@ class XEP_0115(BasePlugin):
self.xmpp.event('entity_caps_legacy', pres)
return
+ ver = pres['caps']['ver']
+
existing_verstring = self.get_verstring(pres['from'].full)
- if str(existing_verstring) == str(pres['caps']['ver']):
+ if str(existing_verstring) == str(ver):
return
- existing_caps = self.get_caps(verstring=pres['caps']['ver'])
+ existing_caps = self.get_caps(verstring=ver)
if existing_caps is not None:
- self.assign_verstring(pres['from'], pres['caps']['ver'])
+ self.assign_verstring(pres['from'], ver)
return
if pres['caps']['hash'] not in self.hashes:
@@ -156,9 +161,16 @@ class XEP_0115(BasePlugin):
except XMPPError:
return
- log.debug("New caps verification string: %s", pres['caps']['ver'])
+ # Only lookup the same caps once at a time.
+ with self._processing_lock:
+ if ver in self._processing:
+ log.debug('Already processing verstring %s' % ver)
+ return
+ self._processing.add(ver)
+
+ log.debug("New caps verification string: %s", ver)
try:
- node = '%s#%s' % (pres['caps']['node'], pres['caps']['ver'])
+ node = '%s#%s' % (pres['caps']['node'], ver)
caps = self.xmpp['xep_0030'].get_info(pres['from'], node)
if isinstance(caps, Iq):
@@ -168,7 +180,10 @@ class XEP_0115(BasePlugin):
pres['caps']['ver']):
self.assign_verstring(pres['from'], pres['caps']['ver'])
except XMPPError:
- log.debug("Could not retrieve disco#info results for caps")
+ log.debug("Could not retrieve disco#info results for caps for %s", node)
+
+ with self._processing_lock:
+ self._processing.remove(ver)
def _validate_caps(self, caps, hash, check_verstring):
# Check Identities
@@ -179,7 +194,6 @@ class XEP_0115(BasePlugin):
return False
# Check Features
-
full_features = caps.get_features(dedupe=False)
deduped_features = caps.get_features()
if len(full_features) != len(deduped_features):
@@ -272,7 +286,7 @@ class XEP_0115(BasePlugin):
binary = hash(S.encode('utf8')).digest()
return base64.b64encode(binary).decode('utf-8')
- def update_caps(self, jid=None, node=None):
+ def update_caps(self, jid=None, node=None, preserve=False):
try:
info = self.xmpp['xep_0030'].get_info(jid, node, local=True)
if isinstance(info, Iq):
@@ -286,19 +300,11 @@ class XEP_0115(BasePlugin):
self.assign_verstring(jid, ver)
if self.xmpp.session_started_event.is_set() and self.broadcast:
- # Check if we've sent directed presence. If we haven't, we
- # can just send a normal presence stanza. If we have, then
- # we will send presence to each contact individually so
- # that we don't clobber existing statuses.
- directed = False or self.xmpp.is_component
- for contact in self.xmpp.roster[jid]:
- if self.xmpp.roster[jid][contact].last_status is not None:
- directed = True
- if not directed:
- self.xmpp.roster[jid].send_last_presence()
- else:
+ if self.xmpp.is_component or preserve:
for contact in self.xmpp.roster[jid]:
self.xmpp.roster[jid][contact].send_last_presence()
+ else:
+ self.xmpp.roster[jid].send_last_presence()
except XMPPError:
return
--
cgit v1.2.3
From cdeae7e72fb1d624fc45ffafcef08e30ac606720 Mon Sep 17 00:00:00 2001
From: Lance Stout <lancestout@gmail.com>
Date: Mon, 11 Feb 2013 19:53:57 -0800
Subject: Make legacy caps log more useful, until we support legacy caps.
---
sleekxmpp/plugins/xep_0115/caps.py | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/sleekxmpp/plugins/xep_0115/caps.py b/sleekxmpp/plugins/xep_0115/caps.py
index 1d8d9e42..fac1cc7c 100644
--- a/sleekxmpp/plugins/xep_0115/caps.py
+++ b/sleekxmpp/plugins/xep_0115/caps.py
@@ -138,7 +138,10 @@ class XEP_0115(BasePlugin):
def _process_caps(self, pres):
if not pres['caps']['hash']:
- log.debug("Received unsupported legacy caps.")
+ log.debug("Received unsupported legacy caps: %s, %s, %s",
+ pres['caps']['node'],
+ pres['caps']['ver'],
+ pres['caps']['ext'])
self.xmpp.event('entity_caps_legacy', pres)
return
--
cgit v1.2.3
From 99ecb166d377ea316c95830a74efc73f5c2b9182 Mon Sep 17 00:00:00 2001
From: Lance Stout <lancestout@gmail.com>
Date: Mon, 11 Feb 2013 20:01:53 -0800
Subject: More caps cleanup
---
sleekxmpp/plugins/xep_0115/caps.py | 43 ++++++++++++++++++++------------------
1 file changed, 23 insertions(+), 20 deletions(-)
diff --git a/sleekxmpp/plugins/xep_0115/caps.py b/sleekxmpp/plugins/xep_0115/caps.py
index fac1cc7c..41b5c52e 100644
--- a/sleekxmpp/plugins/xep_0115/caps.py
+++ b/sleekxmpp/plugins/xep_0115/caps.py
@@ -207,29 +207,32 @@ class XEP_0115(BasePlugin):
form_types = []
deduped_form_types = set()
for stanza in caps['substanzas']:
- if isinstance(stanza, self.xmpp['xep_0004'].stanza.Form):
- if 'FORM_TYPE' in stanza['fields']:
- f_type = tuple(stanza['fields']['FORM_TYPE']['value'])
- form_types.append(f_type)
- deduped_form_types.add(f_type)
- if len(form_types) != len(deduped_form_types):
- log.debug("Duplicated FORM_TYPE values, " + \
- "invalid for caps")
+ if not isinstance(stanza, self.xmpp['xep_0004'].stanza.Form):
+ log.debug("Non form extension found, ignoring for caps")
+ caps.xml.remove(stanza.xml)
+ continue
+ if 'FORM_TYPE' in stanza['fields']:
+ f_type = tuple(stanza['fields']['FORM_TYPE']['value'])
+ form_types.append(f_type)
+ deduped_form_types.add(f_type)
+ if len(form_types) != len(deduped_form_types):
+ log.debug("Duplicated FORM_TYPE values, " + \
+ "invalid for caps")
+ return False
+
+ if len(f_type) > 1:
+ deduped_type = set(f_type)
+ if len(f_type) != len(deduped_type):
+ log.debug("Extra FORM_TYPE data, invalid for caps")
return False
- if len(f_type) > 1:
- deduped_type = set(f_type)
- if len(f_type) != len(deduped_type):
- log.debug("Extra FORM_TYPE data, invalid for caps")
- return False
-
- if stanza['fields']['FORM_TYPE']['type'] != 'hidden':
- log.debug("Field FORM_TYPE type not 'hidden', " + \
- "ignoring form for caps")
- caps.xml.remove(stanza.xml)
- else:
- log.debug("No FORM_TYPE found, ignoring form for caps")
+ if stanza['fields']['FORM_TYPE']['type'] != 'hidden':
+ log.debug("Field FORM_TYPE type not 'hidden', " + \
+ "ignoring form for caps")
caps.xml.remove(stanza.xml)
+ else:
+ log.debug("No FORM_TYPE found, ignoring form for caps")
+ caps.xml.remove(stanza.xml)
verstring = self.generate_verstring(caps, hash)
if verstring != check_verstring:
--
cgit v1.2.3
From 55e50ad9798247f1730ae51ebe39e9ebf3a643a9 Mon Sep 17 00:00:00 2001
From: Lance Stout <lancestout@gmail.com>
Date: Tue, 12 Feb 2013 01:30:44 -0800
Subject: Add XEP-0079 Advanced Message Processing plugin.
---
sleekxmpp/plugins/__init__.py | 1 +
sleekxmpp/plugins/xep_0079/__init__.py | 18 +++++++
sleekxmpp/plugins/xep_0079/amp.py | 79 ++++++++++++++++++++++++++++
sleekxmpp/plugins/xep_0079/stanza.py | 96 ++++++++++++++++++++++++++++++++++
4 files changed, 194 insertions(+)
create mode 100644 sleekxmpp/plugins/xep_0079/__init__.py
create mode 100644 sleekxmpp/plugins/xep_0079/amp.py
create mode 100644 sleekxmpp/plugins/xep_0079/stanza.py
diff --git a/sleekxmpp/plugins/__init__.py b/sleekxmpp/plugins/__init__.py
index c2d89c46..61b5ff9c 100644
--- a/sleekxmpp/plugins/__init__.py
+++ b/sleekxmpp/plugins/__init__.py
@@ -35,6 +35,7 @@ __all__ = [
'xep_0066', # Out of Band Data
'xep_0077', # In-Band Registration
# 'xep_0078', # Non-SASL auth. Don't automatically load
+ 'xep_0079', # Advanced Message Processing
'xep_0080', # User Location
'xep_0082', # XMPP Date and Time Profiles
'xep_0084', # User Avatar
diff --git a/sleekxmpp/plugins/xep_0079/__init__.py b/sleekxmpp/plugins/xep_0079/__init__.py
new file mode 100644
index 00000000..09e66715
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0079/__init__.py
@@ -0,0 +1,18 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2013 Nathanael C. Fritz, Lance J.T. Stout
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.plugins.base import register_plugin
+
+from sleekxmpp.plugins.xep_0079.stanza import (
+ AMP, Rule, InvalidRules, UnsupportedConditions,
+ UnsupportedActions, FailedRules, FailedRule,
+ AMPFeature)
+from sleekxmpp.plugins.xep_0079.amp import XEP_0079
+
+
+register_plugin(XEP_0079)
diff --git a/sleekxmpp/plugins/xep_0079/amp.py b/sleekxmpp/plugins/xep_0079/amp.py
new file mode 100644
index 00000000..918fb841
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0079/amp.py
@@ -0,0 +1,79 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2013 Nathanael C. Fritz, Lance J.T. Stout
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permissio
+"""
+
+import logging
+
+from sleekxmpp.stanza import Message, Error, StreamFeatures
+from sleekxmpp.xmlstream import register_stanza_plugin
+from sleekxmpp.xmlstream.matcher import StanzaPath, MatchMany
+from sleekxmpp.xmlstream.handler import Callback
+from sleekxmpp.plugins import BasePlugin
+from sleekxmpp.plugins.xep_0079 import stanza
+
+
+log = logging.getLogger(__name__)
+
+
+class XEP_0079(BasePlugin):
+
+ """
+ XEP-0079 Advanced Message Processing
+ """
+
+ name = 'xep_0079'
+ description = 'XEP-0079: Advanced Message Processing'
+ dependencies = set(['xep_0030'])
+ stanza = stanza
+
+ def plugin_init(self):
+ register_stanza_plugin(Message, stanza.AMP)
+ register_stanza_plugin(Error, stanza.InvalidRules)
+ register_stanza_plugin(Error, stanza.UnsupportedConditions)
+ register_stanza_plugin(Error, stanza.UnsupportedActions)
+ register_stanza_plugin(Error, stanza.FailedRules)
+
+ self.xmpp.register_handler(
+ Callback('AMP Response',
+ MatchMany([
+ StanzaPath('message/error/failed_rules'),
+ StanzaPath('message/amp')
+ ]),
+ self._handle_amp_response))
+
+ if not self.xmpp.is_component:
+ self.xmpp.register_feature('amp',
+ self._handle_amp_feature,
+ restart=False,
+ order=9000)
+ register_stanza_plugin(StreamFeatures, stanza.AMPFeature)
+
+ def plugin_end(self):
+ self.xmpp.remove_handler('AMP Response')
+
+ def _handle_amp_response(self, msg):
+ log.debug('>>>>>>>>>>>>>>>>>>>>>>>>>>>>>')
+ if msg['type'] == 'error':
+ self.xmpp.event('amp_error', msg)
+ elif msg['amp']['status'] in ('alert', 'notify'):
+ self.xmpp.event('amp_%s' % msg['amp']['status'], msg)
+
+ def _handle_amp_feature(self, features):
+ log.debug('Advanced Message Processing is available.')
+ self.xmpp.features.add('amp')
+
+ def discover_support(self, jid=None, **iqargs):
+ if jid is None:
+ if self.xmpp.is_component:
+ jid = self.xmpp.server_host
+ else:
+ jid = self.xmpp.boundjid.host
+
+ return self.xmpp['xep_0030'].get_info(
+ jid=jid,
+ node='http://jabber.org/protocol/amp',
+ **iqargs)
diff --git a/sleekxmpp/plugins/xep_0079/stanza.py b/sleekxmpp/plugins/xep_0079/stanza.py
new file mode 100644
index 00000000..cb6932d6
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0079/stanza.py
@@ -0,0 +1,96 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2013 Nathanael C. Fritz, Lance J.T. Stout
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from __future__ import unicode_literals
+
+from sleekxmpp.xmlstream import ElementBase, register_stanza_plugin
+
+
+class AMP(ElementBase):
+ namespace = 'http://jabber.org/protocol/amp'
+ name = 'amp'
+ plugin_attrib = 'amp'
+ interfaces = set(['from', 'to', 'status', 'per_hop'])
+
+ def get_from(self):
+ return JID(self._get_attr('from'))
+
+ def set_from(self, value):
+ return self._set_attr('from', str(value))
+
+ def get_to(self):
+ return JID(self._get_attr('from'))
+
+ def set_to(self, value):
+ return self._set_attr('to', str(value))
+
+ def get_per_hop(self):
+ return self._get_attr('per-hop') == 'true'
+
+ def set_per_hop(self, value):
+ if value:
+ return self._set_attr('per-hop', 'true')
+ else:
+ return self._del_attr('per-hop')
+
+ def del_per_hop(self):
+ return self._del_attr('per-hop')
+
+ def add_rule(self, action, condition, value):
+ rule = Rule(parent=self)
+ rule['action'] = action
+ rule['condition'] = condition
+ rule['value'] = value
+
+
+class Rule(ElementBase):
+ namespace = 'http://jabber.org/protocol/amp'
+ name = 'rule'
+ plugin_attrib = name
+ plugin_multi_attrib = 'rules'
+ interfaces = set(['action', 'condition', 'value'])
+
+
+class InvalidRules(ElementBase):
+ namespace = 'http://jabber.org/protocol/amp'
+ name = 'invalid-rules'
+ plugin_attrib = 'invalid_rules'
+
+
+class UnsupportedConditions(ElementBase):
+ namespace = 'http://jabber.org/protocol/amp'
+ name = 'unsupported-conditions'
+ plugin_attrib = 'unsupported_conditions'
+
+
+class UnsupportedActions(ElementBase):
+ namespace = 'http://jabber.org/protocol/amp'
+ name = 'unsupported-actions'
+ plugin_attrib = 'unsupported_actions'
+
+
+class FailedRule(Rule):
+ namespace = 'http://jabber.org/protocol/amp#errors'
+
+
+class FailedRules(ElementBase):
+ namespace = 'http://jabber.org/protocol/amp#errors'
+ name = 'failed-rules'
+ plugin_attrib = 'failed_rules'
+
+
+class AMPFeature(ElementBase):
+ namespace = 'http://jabber.org/features/amp'
+ name = 'amp'
+
+
+register_stanza_plugin(AMP, Rule, iterable=True)
+register_stanza_plugin(InvalidRules, Rule, iterable=True)
+register_stanza_plugin(UnsupportedConditions, Rule, iterable=True)
+register_stanza_plugin(UnsupportedActions, Rule, iterable=True)
+register_stanza_plugin(FailedRules, FailedRule, iterable=True)
--
cgit v1.2.3