Break reference cycle to fix potential memory leaks for callback handlers.

sleekxmpp/xmlstream/handler/base.py

@@ -6,6 +6,8 @@
     See the file LICENSE for copying permission.
 """
 
+import weakref
+
 
 class BaseHandler(object):
 
@@ -43,7 +45,10 @@ class BaseHandler(object):
             stream  -- The XMLStream instance the handler should monitor.
         """
         self.name = name
-        self.stream = stream
+        if stream is not None:
+            self.stream = weakref.ref(stream)
+        else:
+            self.stream = None
         self._destroy = False
         self._payload = None
         self._matcher = matcher

sleekxmpp/xmlstream/handler/waiter.py

@@ -85,14 +85,14 @@ class Waiter(BaseHandler):
                        value sleekxmpp.xmlstream.RESPONSE_TIMEOUT.
         """
         if timeout is None:
-            timeout = self.stream.response_timeout
+            timeout = self.stream().response_timeout
 
         try:
             stanza = self._payload.get(True, timeout)
         except queue.Empty:
             stanza = False
             log.warning("Timed out waiting for %s" % self.name)
-        self.stream.removeHandler(self.name)
+        self.stream().remove_handler(self.name)
         return stanza
 
     def check_delete(self):

sleekxmpp/xmlstream/xmlstream.py

@@ -19,6 +19,7 @@ import threading
 import time
 import types
 import random
+import weakref
 try:
     import queue
 except ImportError:
@@ -719,7 +720,7 @@ class XMLStream(object):
         """
         if handler.stream is None:
             self.__handlers.append(handler)
-            handler.stream = self
+            handler.stream = weakref.ref(self)
 
     def remove_handler(self, name):
         """