Allow IQ timeouts to be asynchronous, by passing a timeout_callback parameter to send(). An example modification of disco is included. If this approach is approved, I'll go through and update the other plugins.

sleekxmpp/stanza/iq.py

@@ -154,7 +154,7 @@ class Iq(RootStanza):
         StanzaBase.reply(self, clear)
         return self
 
-    def send(self, block=True, timeout=None, callback=None, now=False):
+    def send(self, block=True, timeout=None, callback=None, now=False, timeout_callback=None):
         """
         Send an <iq> stanza over the XML stream.
 
@@ -181,15 +181,32 @@ class Iq(RootStanza):
             now      -- Indicates if the send queue should be skipped and send
                         the stanza immediately. Used during stream
                         initialization. Defaults to False.
+            timeout_callback -- Optional reference to a stream handler function.
+                        Will be executed when the timeout expires before a 
+                        response has been received with the originally-sent IQ 
+                        stanza.  Only called if there is a callback parameter
+                        (and therefore are in async mode).
         """
         if timeout is None:
             timeout = self.stream.response_timeout
         if callback is not None and self['type'] in ('get', 'set'):
             handler_name = 'IqCallback_%s' % self['id']
-            handler = Callback(handler_name,
-                               MatcherId(self['id']),
-                               callback,
-                               once=True)
+            if timeout_callback:
+                self.callback = callback
+                self.timeout_callback = timeout_callback
+                self.stream.schedule('IqTimeout_%s' % self['id'], 
+                                     timeout, 
+                                     self._fire_timeout, 
+                                     repeat=False)            
+                handler = Callback(handler_name,
+                                   MatcherId(self['id']),
+                                   self._handle_result,
+                                   once=True)
+            else:
+                handler = Callback(handler_name,
+                                   MatcherId(self['id']),
+                                   callback,
+                                   once=True)
             self.stream.register_handler(handler)
             StanzaBase.send(self, now=now)
             return handler_name
@@ -206,6 +223,16 @@ class Iq(RootStanza):
         else:
             return StanzaBase.send(self, now=now)
 
+    def _handle_result(self, iq):
+        # we got the IQ, so don't fire the timeout
+        self.stream.scheduler.remove('IqTimeout_%s' % self['id'])
+        self.callback(iq)
+
+    def _fire_timeout(self):
+        # don't fire the handler for the IQ, if it finally does come in
+        self.stream.remove_handler('IqCallback_%s' % self['id'])
+        self.timeout_callback(self)
+
     def _set_stanza_values(self, values):
         """
         Set multiple stanza interface values using a dictionary.