--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sat/plugins/plugin_xep_0359.py	Sat Dec 01 09:57:25 2018 +0100
@@ -0,0 +1,102 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+# SAT plugin for Message Archive Management (XEP-0359)
+# Copyright (C) 2009-2018 Jérôme Poisson (goffi@goffi.org)
+# Copyright (C) 2013-2016 Adrien Cossa (souliane@mailoo.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 sat.core.constants import Const as C
+from sat.core import exceptions
+from sat.core.i18n import _
+from sat.core.log import getLogger
+from twisted.words.protocols.jabber import xmlstream
+from zope.interface import implements
+from wokkel import disco
+
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: u"Unique and Stable Stanza IDs",
+    C.PI_IMPORT_NAME: u"XEP-0359",
+    C.PI_TYPE: u"XEP",
+    C.PI_PROTOCOLS: [u"XEP-0359"],
+    C.PI_MAIN: u"XEP_0359",
+    C.PI_HANDLER: u"yes",
+    C.PI_DESCRIPTION: _(u"""Implementation of Unique and Stable Stanza IDs"""),
+}
+
+NS_SID = u"urn:xmpp:sid:0"
+
+
+class XEP_0359(object):
+
+    def __init__(self, host):
+        log.info(_(u"Unique and Stable Stanza IDs plugin initialization"))
+        self.host = host
+        host.registerNamespace(u"stanza_id", NS_SID)
+        host.trigger.add(u"message_parse", self._message_parseTrigger)
+
+    def _message_parseTrigger(self, client, message_elt, mess_data):
+        """Check if message has a stanza-id"""
+        stanza_id = self.getStanzaId(message_elt, client.jid.userhostJID())
+        if stanza_id is not None:
+            mess_data[u'extra'][u'stanza_id'] = stanza_id
+        return True
+
+    def getStanzaId(self, element, by):
+        """Return stanza-id if found in element
+
+        @param element(domish.Element): element to parse
+        @param by(jid.JID): entity which should have set a stanza-id
+        @return (unicode, None): stanza-id if found
+        """
+        stanza_id = None
+        for stanza_elt in element.elements(NS_SID, u"stanza-id"):
+            if stanza_elt.getAttribute(u"by") == by.full():
+                if stanza_id is not None:
+                    # we must not have more than one element (§3 #4)
+                    raise exceptions.DataError(
+                        u"More than one corresponding stanza-id found!")
+                stanza_id = stanza_elt.getAttribute(u"id")
+                # we don't break to be sure that there is no more than one element
+                # with this "by" attribute
+
+        return stanza_id
+
+    def addStanzaId(self, client, element, stanza_id, by=None):
+        """Add a <stanza-id/> to a stanza
+
+        @param element(domish.Element): stanza where the <stanza-id/> must be added
+        @param stanza_id(unicode): id to use
+        @param by(jid.JID, None): jid to use or None to use client.jid
+        """
+        sid_elt = element.addElement((NS_SID, u"stanza-id"))
+        sid_elt[u"by"] = client.jid.userhost() if by is None else by.userhost()
+        sid_elt[u"id"] = stanza_id
+
+    def getHandler(self, client):
+        return XEP_0359_handler()
+
+
+class XEP_0359_handler(xmlstream.XMPPHandler):
+    implements(disco.IDisco)
+
+    def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
+        return [disco.DiscoFeature(NS_SID)]
+
+    def getDiscoItems(self, requestor, target, nodeIdentifier=""):
+        return []