Add support for roster versioning.

This was XEP-0237, but is now part of RFC 6121.

Roster backends should now expose two additional methods:

version(jid):
    Return the version of the given JID's roster.
set_version(jid, version):
    Update the version of the given JID's roster.

A new state field will be passed to the backend if an item
has been marked for removal. This is 'removed' which will
be set to True.

1 files changed, 42 insertions, 0 deletions

diff --git a/sleekxmpp/features/feature_rosterver/rosterver.py b/sleekxmpp/features/feature_rosterver/rosterver.py
new file mode 100644
index 00000000..059d20e1
--- /dev/null
+++ b/sleekxmpp/features/feature_rosterver/rosterver.py
@@ -0,0 +1,42 @@
+"""
+    SleekXMPP: The Sleek XMPP Library
+    Copyright (C) 2012  Nathanael C. Fritz
+    This file is part of SleekXMPP.
+
+    See the file LICENSE for copying permission.
+"""
+
+import logging
+
+from sleekxmpp.stanza import Iq, StreamFeatures
+from sleekxmpp.features.feature_rosterver import stanza
+from sleekxmpp.xmlstream import register_stanza_plugin
+from sleekxmpp.plugins.base import base_plugin
+
+
+log = logging.getLogger(__name__)
+
+
+class feature_rosterver(base_plugin):
+
+    def plugin_init(self):
+        self.name = 'Roster Versioning'
+        self.rfc = '6121'
+        self.description = 'Roster Versioning'
+        self.stanza = stanza
+
+        self.xmpp.register_feature('rosterver',
+                self._handle_rosterver,
+                restart=False,
+                order=9000)
+
+        register_stanza_plugin(StreamFeatures, stanza.RosterVer)
+
+    def _handle_rosterver(self, features):
+        """Enable using roster versioning.
+
+        Arguments:
+            features -- The stream features stanza.
+        """
+        log.debug("Enabling roster versioning.")
+        self.xmpp.features.add('rosterver')