Fixed shutdown RpcConnection memory leak problem with RpcServer

sjrpc/server/simple.py

-
+import gc
 import ssl
 import time
 import errno
 import socket
 import select
+import weakref
 import logging
 import threading
-
 from sjrpc.core import RpcConnection
 
 import pyev
@@ -62,6 +62,16 @@ class RpcServer(object):
             conn = self._wrap(sock)
             self.register(conn)
 
+    def _clean_conn(self, ref):
+        '''
+        Callback called by weakref when an object is about to be collected by
+        garbage collector.
+        '''
+        try:
+            self._clients.remove(ref)
+        except KeyError:
+            pass
+
 #
 # Public methods:
 #
@@ -72,7 +82,10 @@ class RpcServer(object):
 
         :param conn: the connection to register.
         '''
-        self._clients.add(conn)
+        self._clients.add(weakref.ref(conn, self._clean_conn))
+        gc.collect() # Force a manual garbage collection to avoid memory leak
+                     # with RpcConnections. This is maybe not required but I
+                     # need to read docs about python's gc and circular refs.
 
     def unregister(self, conn, shutdown=False):
         '''
@@ -85,7 +98,6 @@ class RpcServer(object):
         if conn in self._clients:
             if shutdown:
                 conn.shutdown()
-            self._clients.remove(conn)
 
     def run(self):
         '''