Add stream feature for server support of subscription pre-approvals.

sleekxmpp/features/feature_preapproval/preapproval.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_preapproval import stanza
+from sleekxmpp.xmlstream import register_stanza_plugin
+from sleekxmpp.plugins.base import BasePlugin
+
+
+log = logging.getLogger(__name__)
+
+
+class FeaturePreApproval(BasePlugin):
+
+    name = 'feature_preapproval'
+    description = 'RFC 6121: Stream Feature: Subscription Pre-Approval'
+    dependences = set()
+    stanza = stanza
+
+    def plugin_init(self):
+        self.xmpp.register_feature('preapproval',
+                self._handle_preapproval,
+                restart=False,
+                order=9001)
+
+        register_stanza_plugin(StreamFeatures, stanza.PreApproval)
+
+    def _handle_preapproval(self, features):
+        """Save notice that the server support subscription pre-approvals.
+
+        Arguments:
+            features -- The stream features stanza.
+        """
+        log.debug("Server supports subscription pre-approvals.")
+        self.xmpp.features.add('preapproval')