+++ /dev/null
-# Copyright (c) 2009-2010 Denis Bilenko, denis.bilenko at gmail com
-# Copyright (c) 2010 Eventlet Contributors (see AUTHORS)
-# and licensed under the MIT license:
-#
-# 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.support import greenlets as greenlet
-
-from eventlet.support import greenlets as greenlet
-from eventlet.hubs import get_hub
-
-__all__ = ['Timeout',
- 'with_timeout']
-
-_NONE = object()
-
-# deriving from BaseException so that "except Exception as e" doesn't catch
-# Timeout exceptions.
-
-
-class Timeout(BaseException):
- """Raises *exception* in the current greenthread after *timeout* seconds.
-
- When *exception* is omitted or ``None``, the :class:`Timeout` instance
- itself is raised. If *seconds* is None, the timer is not scheduled, and is
- only useful if you're planning to raise it directly.
-
- Timeout objects are context managers, and so can be used in with statements.
- When used in a with statement, if *exception* is ``False``, the timeout is
- still raised, but the context manager suppresses it, so the code outside the
- with-block won't see it.
- """
-
- def __init__(self, seconds=None, exception=None):
- self.seconds = seconds
- self.exception = exception
- self.timer = None
- self.start()
-
- def start(self):
- """Schedule the timeout. This is called on construction, so
- it should not be called explicitly, unless the timer has been
- canceled."""
- assert not self.pending, \
- '%r is already started; to restart it, cancel it first' % self
- if self.seconds is None: # "fake" timeout (never expires)
- self.timer = None
- elif self.exception is None or isinstance(self.exception, bool): # timeout that raises self
- self.timer = get_hub().schedule_call_global(
- self.seconds, greenlet.getcurrent().throw, self)
- else: # regular timeout with user-provided exception
- self.timer = get_hub().schedule_call_global(
- self.seconds, greenlet.getcurrent().throw, self.exception)
- return self
-
- @property
- def pending(self):
- """True if the timeout is scheduled to be raised."""
- if self.timer is not None:
- return self.timer.pending
- else:
- return False
-
- def cancel(self):
- """If the timeout is pending, cancel it. If not using
- Timeouts in ``with`` statements, always call cancel() in a
- ``finally`` after the block of code that is getting timed out.
- If not canceled, the timeout will be raised later on, in some
- unexpected section of the application."""
- if self.timer is not None:
- self.timer.cancel()
- self.timer = None
-
- def __repr__(self):
- classname = self.__class__.__name__
- if self.pending:
- pending = ' pending'
- else:
- pending = ''
- if self.exception is None:
- exception = ''
- else:
- exception = ' exception=%r' % self.exception
- return '<%s at %s seconds=%s%s%s>' % (
- classname, hex(id(self)), self.seconds, exception, pending)
-
- def __str__(self):
- """
- >>> raise Timeout # doctest: +IGNORE_EXCEPTION_DETAIL
- Traceback (most recent call last):
- ...
- Timeout
- """
- if self.seconds is None:
- return ''
- if self.seconds == 1:
- suffix = ''
- else:
- suffix = 's'
- if self.exception is None or self.exception is True:
- return '%s second%s' % (self.seconds, suffix)
- elif self.exception is False:
- return '%s second%s (silent)' % (self.seconds, suffix)
- else:
- return '%s second%s (%s)' % (self.seconds, suffix, self.exception)
-
- def __enter__(self):
- if self.timer is None:
- self.start()
- return self
-
- def __exit__(self, typ, value, tb):
- self.cancel()
- if value is self and self.exception is False:
- return True
-
-
-def with_timeout(seconds, function, *args, **kwds):
- """Wrap a call to some (yielding) function with a timeout; if the called
- function fails to return before the timeout, cancel it and return a flag
- value.
- """
- timeout_value = kwds.pop("timeout_value", _NONE)
- timeout = Timeout(seconds)
- try:
- try:
- return function(*args, **kwds)
- except Timeout as ex:
- if ex is timeout and timeout_value is not _NONE:
- return timeout_value
- raise
- finally:
- timeout.cancel()
Code Review / packages / trusty / python-eventlet.git / blobdiff