Allow sending stanzas on session_end.

May set self.disconnect_wait=True so that all disconnect
calls wait for the send queue to empty, unless explicitly
overridden with wait=False.

The session_end now fires before closing the socket so
that final stanzas may be sent, such as unavailable presences
for components.

sleekxmpp/xmlstream/xmlstream.py

@@ -276,6 +276,13 @@ class XMLStream(object):
         #: the stream will be restarted in the event of an error.
         self.auto_reconnect = True
 
+        #: The :attr:`disconnect_wait` setting is the default value
+        #: for controlling if the system waits for the send queue to
+        #: empty before ending the stream. This may be overridden by
+        #: passing ``wait=True`` or ``wait=False`` to :meth:`disconnect`.
+        #: The default :attr:`disconnect_wait` value is ``False``.
+        self.disconnect_wait = False
+
         #: A list of DNS results that have not yet been tried.
         self.dns_answers = []
 
@@ -402,6 +409,7 @@ class XMLStream(object):
             try:
                 while elapsed < delay and not self.stop.is_set():
                     time.sleep(0.1)
+                    elapsed += 0.1
             except KeyboardInterrupt:
                 self.stop.set()
                 return False
@@ -519,7 +527,7 @@ class XMLStream(object):
                 self.session_timeout,
                 _handle_session_timeout)
 
-    def disconnect(self, reconnect=False, wait=False):
+    def disconnect(self, reconnect=False, wait=None):
         """Terminate processing and close the XML streams.
 
         Optionally, the connection may be reconnected and
@@ -538,14 +546,20 @@ class XMLStream(object):
                           and processing should be restarted.
                           Defaults to ``False``.
         :param wait: Flag indicating if the send queue should
-                     be emptied before disconnecting.
+                     be emptied before disconnecting, overriding
+                     :attr:`disconnect_wait`.
         """
         self.state.transition('connected', 'disconnected',
                               func=self._disconnect, args=(reconnect, wait))
 
-    def _disconnect(self, reconnect=False, wait=False):
+    def _disconnect(self, reconnect=False, wait=None):
+        self.event('session_end', direct=True)
+
         # Wait for the send queue to empty.
-        if wait:
+        if wait is not None:
+            if wait:
+                self.send_queue.join()
+        elif self.disconnect_wait:
             self.send_queue.join()
 
         # Send the end of stream marker.
@@ -566,7 +580,6 @@ class XMLStream(object):
             self.event('socket_error', serr)
         finally:
             #clear your application state
-            self.event('session_end', direct=True)
             self.event("disconnected", direct=True)
             return True
 
@@ -1119,6 +1132,7 @@ class XMLStream(object):
         # Additional passes will be made only if an error occurs and
         # reconnecting is permitted.
         while True:
+            shutdown = False
             try:
                 # The call to self.__read_xml will block and prevent
                 # the body of the loop from running until a disconnect
@@ -1136,16 +1150,16 @@ class XMLStream(object):
                     if not self.__read_xml():
                         # If the server terminated the stream, end processing
                         break
+            except KeyboardInterrupt:
+                log.debug("Keyboard Escape Detected in _process")
+                self.event('killed', direct=True)
+                shutdown = True
+            except SystemExit:
+                log.debug("SystemExit in _process")
+                shutdown = True
             except SyntaxError as e:
                 log.error("Error reading from XML stream.")
                 self.exception(e)
-            except KeyboardInterrupt:
-                log.debug("Keyboard Escape Detected in _process")
-                self.stop.set()
-            except SystemExit:
-                log.debug("SystemExit in _process")
-                self.stop.set()
-                self.scheduler.quit()
             except Socket.error as serr:
                 self.event('socket_error', serr)
                 log.exception('Socket Error')
@@ -1154,7 +1168,8 @@ class XMLStream(object):
                     log.exception('Connection error.')
                 self.exception(e)
 
-            if not self.stop.is_set() and self.auto_reconnect:
+            if not shutdown and not self.stop.is_set() \
+               and self.auto_reconnect:
                 self.reconnect()
             else:
                 self.disconnect()