SleekXMPP/sleekxmpp/xmlstream/handler/waiter.py
Lance Stout 89fb15e896 Updated the suite of handler classes with documentation.
Updated XMLStream to return True or False from removeHandler to indicate if the handler
existed and was removed.

Waiter handlers now unregister themselves after timing out.
2010-08-27 16:42:26 -04:00

90 lines
2.4 KiB
Python

"""
SleekXMPP: The Sleek XMPP Library
Copyright (C) 2010 Nathanael C. Fritz
This file is part of SleekXMPP.
See the file LICENSE for copying permission.
"""
import logging
try:
import queue
except ImportError:
import Queue as queue
from sleekxmpp.xmlstream import StanzaBase, RESPONSE_TIMEOUT
from sleekxmpp.xmlstream.handler.base import BaseHandler
class Waiter(BaseHandler):
"""
The Waiter handler allows an event handler to block
until a particular stanza has been received. The handler
will either be given the matched stanza, or False if the
waiter has timed out.
Methods:
checkDelete -- Overrides BaseHandler.checkDelete
prerun -- Overrides BaseHandler.prerun
run -- Overrides BaseHandler.run
wait -- Wait for a stanza to arrive and return it to
an event handler.
"""
def __init__(self, name, matcher, stream=None):
BaseHandler.__init__(self, name, matcher)
self._payload = queue.Queue()
def prerun(self, payload):
"""
Store the matched stanza.
Overrides BaseHandler.prerun
Arguments:
payload -- The matched stanza object.
"""
self._payload.put(payload)
def run(self, payload):
"""
Do not process this handler during the main event loop.
Overrides BaseHandler.run
Arguments:
payload -- The matched stanza object.
"""
pass
def wait(self, timeout=RESPONSE_TIMEOUT):
"""
Block an event handler while waiting for a stanza to arrive.
Be aware that this will impact performance if called from a
non-threaded event handler.
Will return either the received stanza, or False if the waiter
timed out.
Arguments:
timeout -- The number of seconds to wait for the stanza to
arrive. Defaults to the global default timeout
value sleekxmpp.xmlstream.RESPONSE_TIMEOUT.
"""
try:
stanza = self._payload.get(True, timeout)
except queue.Empty:
stanza = False
logging.warning("Timed out waiting for %s" % self.name)
self.stream.removeHandler(self.name)
return stanza
def checkDelete(self):
"""
Always remove waiters after use.
Overrides BaseHandler.checkDelete
"""
return True