Files
deb-python-eventlet/eventlet/timer.py
2009-06-12 15:31:40 +07:00

122 lines
4.2 KiB
Python

# @author Bob Ippolito
#
# Copyright (c) 2005-2006, Bob Ippolito
# Copyright (c) 2007, Linden Research, Inc.
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
from eventlet.api import get_hub, getcurrent
""" If true, captures a stack trace for each timer when constructed. This is
useful for debugging leaking timers, to find out where the timer was set up. """
_g_debug = False
class Timer(object):
#__slots__ = ['seconds', 'tpl', 'called', 'cancelled', 'scheduled_time', 'greenlet', 'traceback', 'impltimer']
def __init__(self, seconds, cb, *args, **kw):
"""Create a timer.
seconds: The minimum number of seconds to wait before calling
cb: The callback to call when the timer has expired
*args: The arguments to pass to cb
**kw: The keyword arguments to pass to cb
This timer will not be run unless it is scheduled in a runloop by
calling timer.schedule() or runloop.add_timer(timer).
"""
self._cancelled = False
self.seconds = seconds
self.tpl = cb, args, kw
self.called = False
if _g_debug:
import traceback, cStringIO
self.traceback = cStringIO.StringIO()
traceback.print_stack(file=self.traceback)
@property
def cancelled(self):
return self._cancelled
def __repr__(self):
secs = getattr(self, 'seconds', None)
cb, args, kw = getattr(self, 'tpl', (None, None, None))
retval = "Timer(%s, %s, *%s, **%s)" % (
secs, cb, args, kw)
if _g_debug and hasattr(self, 'traceback'):
retval += '\n' + self.traceback.getvalue()
return retval
def copy(self):
cb, args, kw = self.tpl
return self.__class__(self.seconds, cb, *args, **kw)
def schedule(self):
"""Schedule this timer to run in the current runloop.
"""
self.called = False
self.scheduled_time = get_hub().add_timer(self)
return self
def __call__(self, *args):
if not self.called:
self.called = True
cb, args, kw = self.tpl
try:
cb(*args, **kw)
finally:
get_hub().timer_finished(self)
def cancel(self):
"""Prevent this timer from being called. If the timer has already
been called, has no effect.
"""
self._cancelled = True
self.called = True
get_hub().timer_canceled(self)
try:
del self.tpl
except AttributeError:
pass
class LocalTimer(Timer):
def __init__(self, *args, **kwargs):
self.greenlet = getcurrent()
Timer.__init__(self, *args, **kwargs)
@property
def cancelled(self):
if self.greenlet is None or self.greenlet.dead:
return True
return self._cancelled
def __call__(self, *args):
if not self.called:
self.called = True
if self.greenlet is not None and self.greenlet.dead:
return
cb, args, kw = self.tpl
try:
cb(*args, **kw)
finally:
get_hub().timer_finished(self)
def cancel(self):
self.greenlet = None
Timer.cancel(self)