vmware-nsx/neutron/openstack/common/loopingcall.py
Gary Kotton ee537e33de Update RPC code from oslo
The common RPC code has been updated to include the following:
    8575d87af49ea276341908f83c8c51db13afca44
    8b2b0b743e84ceed7841cf470afed6a5da8e1d07
    23f602940c64ba408d77ceb8f5ba0f67ee4a18ef
    6d0a6c3083218cdac52758a8b6aac6b03402c658
    7cac1ac1bd9df36d4e5183afac3b643df10b1d4d
    8159efddabb09dd9b7c99963ff7c9de0a6c62b62

Updated to include the following in modules in openstack-common.conf:
py3kcompat, sslutils, and versionutils.

The update also includes imports from the RPC code

Change-Id: I84c5b8e2b17da0018dd69ecb354d123a609afe98
2014-01-15 04:26:57 -08:00

146 lines
4.5 KiB
Python

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# Copyright 2011 Justin Santa Barbara
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import sys
from eventlet import event
from eventlet import greenthread
from neutron.openstack.common.gettextutils import _
from neutron.openstack.common import log as logging
from neutron.openstack.common import timeutils
LOG = logging.getLogger(__name__)
class LoopingCallDone(Exception):
"""Exception to break out and stop a LoopingCall.
The poll-function passed to LoopingCall can raise this exception to
break out of the loop normally. This is somewhat analogous to
StopIteration.
An optional return-value can be included as the argument to the exception;
this return-value will be returned by LoopingCall.wait()
"""
def __init__(self, retvalue=True):
""":param retvalue: Value that LoopingCall.wait() should return."""
self.retvalue = retvalue
class LoopingCallBase(object):
def __init__(self, f=None, *args, **kw):
self.args = args
self.kw = kw
self.f = f
self._running = False
self.done = None
def stop(self):
self._running = False
def wait(self):
return self.done.wait()
class FixedIntervalLoopingCall(LoopingCallBase):
"""A fixed interval looping call."""
def start(self, interval, initial_delay=None):
self._running = True
done = event.Event()
def _inner():
if initial_delay:
greenthread.sleep(initial_delay)
try:
while self._running:
start = timeutils.utcnow()
self.f(*self.args, **self.kw)
end = timeutils.utcnow()
if not self._running:
break
delay = interval - timeutils.delta_seconds(start, end)
if delay <= 0:
LOG.warn(_('task run outlasted interval by %s sec') %
-delay)
greenthread.sleep(delay if delay > 0 else 0)
except LoopingCallDone as e:
self.stop()
done.send(e.retvalue)
except Exception:
LOG.exception(_('in fixed duration looping call'))
done.send_exception(*sys.exc_info())
return
else:
done.send(True)
self.done = done
greenthread.spawn_n(_inner)
return self.done
# TODO(mikal): this class name is deprecated in Havana and should be removed
# in the I release
LoopingCall = FixedIntervalLoopingCall
class DynamicLoopingCall(LoopingCallBase):
"""A looping call which sleeps until the next known event.
The function called should return how long to sleep for before being
called again.
"""
def start(self, initial_delay=None, periodic_interval_max=None):
self._running = True
done = event.Event()
def _inner():
if initial_delay:
greenthread.sleep(initial_delay)
try:
while self._running:
idle = self.f(*self.args, **self.kw)
if not self._running:
break
if periodic_interval_max is not None:
idle = min(idle, periodic_interval_max)
LOG.debug(_('Dynamic looping call sleeping for %.02f '
'seconds'), idle)
greenthread.sleep(idle)
except LoopingCallDone as e:
self.stop()
done.send(e.retvalue)
except Exception:
LOG.exception(_('in dynamic looping call'))
done.send_exception(*sys.exc_info())
return
else:
done.send(True)
self.done = done
greenthread.spawn(_inner)
return self.done