Synchronising oslo-incubator service module

Importing service module and its dependencies to enable
openstack common service launcher within glance. This will
be used as the framework for event notifiers and listeners.

This change is a pre-requisite for blueprint
catalog-index-service implementation

All imported modules are new and shouldn't impact any of
the existing glance functionality.

Closes-Bug: #1413861
Partially Implements: blueprint catalog-index-service

Change-Id: Iaa771ead0114e3941667b1e07ff32472d2f77afd
This commit is contained in:
Lakshmi N Sampath 2015-02-04 03:31:22 -08:00
parent d42fd7136d
commit c0858be57d
6 changed files with 1056 additions and 0 deletions

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# Copyright (c) 2012 OpenStack Foundation.
# Administrator of the National Aeronautics and Space Administration.
# 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.
from __future__ import print_function
import copy
import errno
import gc
import logging
import os
import pprint
import socket
import sys
import traceback
import eventlet.backdoor
import greenlet
from oslo.config import cfg
from glance.openstack.common._i18n import _LI
help_for_backdoor_port = (
"Acceptable values are 0, <port>, and <start>:<end>, where 0 results "
"in listening on a random tcp port number; <port> results in listening "
"on the specified port number (and not enabling backdoor if that port "
"is in use); and <start>:<end> results in listening on the smallest "
"unused port number within the specified range of port numbers. The "
"chosen port is displayed in the service's log file.")
eventlet_backdoor_opts = [
cfg.StrOpt('backdoor_port',
help="Enable eventlet backdoor. %s" % help_for_backdoor_port)
]
CONF = cfg.CONF
CONF.register_opts(eventlet_backdoor_opts)
LOG = logging.getLogger(__name__)
def list_opts():
"""Entry point for oslo.config-generator.
"""
return [(None, copy.deepcopy(eventlet_backdoor_opts))]
class EventletBackdoorConfigValueError(Exception):
def __init__(self, port_range, help_msg, ex):
msg = ('Invalid backdoor_port configuration %(range)s: %(ex)s. '
'%(help)s' %
{'range': port_range, 'ex': ex, 'help': help_msg})
super(EventletBackdoorConfigValueError, self).__init__(msg)
self.port_range = port_range
def _dont_use_this():
print("Don't use this, just disconnect instead")
def _find_objects(t):
return [o for o in gc.get_objects() if isinstance(o, t)]
def _print_greenthreads():
for i, gt in enumerate(_find_objects(greenlet.greenlet)):
print(i, gt)
traceback.print_stack(gt.gr_frame)
print()
def _print_nativethreads():
for threadId, stack in sys._current_frames().items():
print(threadId)
traceback.print_stack(stack)
print()
def _parse_port_range(port_range):
if ':' not in port_range:
start, end = port_range, port_range
else:
start, end = port_range.split(':', 1)
try:
start, end = int(start), int(end)
if end < start:
raise ValueError
return start, end
except ValueError as ex:
raise EventletBackdoorConfigValueError(port_range, ex,
help_for_backdoor_port)
def _listen(host, start_port, end_port, listen_func):
try_port = start_port
while True:
try:
return listen_func((host, try_port))
except socket.error as exc:
if (exc.errno != errno.EADDRINUSE or
try_port >= end_port):
raise
try_port += 1
def initialize_if_enabled():
backdoor_locals = {
'exit': _dont_use_this, # So we don't exit the entire process
'quit': _dont_use_this, # So we don't exit the entire process
'fo': _find_objects,
'pgt': _print_greenthreads,
'pnt': _print_nativethreads,
}
if CONF.backdoor_port is None:
return None
start_port, end_port = _parse_port_range(str(CONF.backdoor_port))
# NOTE(johannes): The standard sys.displayhook will print the value of
# the last expression and set it to __builtin__._, which overwrites
# the __builtin__._ that gettext sets. Let's switch to using pprint
# since it won't interact poorly with gettext, and it's easier to
# read the output too.
def displayhook(val):
if val is not None:
pprint.pprint(val)
sys.displayhook = displayhook
sock = _listen('localhost', start_port, end_port, eventlet.listen)
# In the case of backdoor port being zero, a port number is assigned by
# listen(). In any case, pull the port number out here.
port = sock.getsockname()[1]
LOG.info(
_LI('Eventlet backdoor listening on %(port)s for process %(pid)d') %
{'port': port, 'pid': os.getpid()}
)
eventlet.spawn_n(eventlet.backdoor.backdoor_server, sock,
locals=backdoor_locals)
return port

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# 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 logging
import sys
import time
from eventlet import event
from eventlet import greenthread
from glance.openstack.common._i18n import _LE, _LW
LOG = logging.getLogger(__name__)
# NOTE(zyluo): This lambda function was declared to avoid mocking collisions
# with time.time() called in the standard logging module
# during unittests.
_ts = lambda: time.time()
class LoopingCallDone(Exception):
"""Exception to break out and stop a LoopingCallBase.
The poll-function passed to LoopingCallBase 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 LoopingCallBase.wait()
"""
def __init__(self, retvalue=True):
""":param retvalue: Value that LoopingCallBase.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 = _ts()
self.f(*self.args, **self.kw)
end = _ts()
if not self._running:
break
delay = end - start - interval
if delay > 0:
LOG.warn(_LW('task %(func_name)r run outlasted '
'interval by %(delay).2f sec'),
{'func_name': self.f, 'delay': delay})
greenthread.sleep(-delay if delay < 0 else 0)
except LoopingCallDone as e:
self.stop()
done.send(e.retvalue)
except Exception:
LOG.exception(_LE('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
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 %(func_name)r sleeping '
'for %(idle).02f seconds',
{'func_name': self.f, 'idle': idle})
greenthread.sleep(idle)
except LoopingCallDone as e:
self.stop()
done.send(e.retvalue)
except Exception:
LOG.exception(_LE('in dynamic looping call'))
done.send_exception(*sys.exc_info())
return
else:
done.send(True)
self.done = done
greenthread.spawn(_inner)
return self.done

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# 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.
"""Generic Node base class for all workers that run on hosts."""
import errno
import logging
import os
import random
import signal
import sys
import time
try:
# Importing just the symbol here because the io module does not
# exist in Python 2.6.
from io import UnsupportedOperation # noqa
except ImportError:
# Python 2.6
UnsupportedOperation = None
import eventlet
from eventlet import event
from oslo.config import cfg
from glance.openstack.common import eventlet_backdoor
from glance.openstack.common._i18n import _LE, _LI, _LW
from glance.openstack.common import systemd
from glance.openstack.common import threadgroup
CONF = cfg.CONF
LOG = logging.getLogger(__name__)
def _sighup_supported():
return hasattr(signal, 'SIGHUP')
def _is_daemon():
# The process group for a foreground process will match the
# process group of the controlling terminal. If those values do
# not match, or ioctl() fails on the stdout file handle, we assume
# the process is running in the background as a daemon.
# http://www.gnu.org/software/bash/manual/bashref.html#Job-Control-Basics
try:
is_daemon = os.getpgrp() != os.tcgetpgrp(sys.stdout.fileno())
except OSError as err:
if err.errno == errno.ENOTTY:
# Assume we are a daemon because there is no terminal.
is_daemon = True
else:
raise
except UnsupportedOperation:
# Could not get the fileno for stdout, so we must be a daemon.
is_daemon = True
return is_daemon
def _is_sighup_and_daemon(signo):
if not (_sighup_supported() and signo == signal.SIGHUP):
# Avoid checking if we are a daemon, because the signal isn't
# SIGHUP.
return False
return _is_daemon()
def _signo_to_signame(signo):
signals = {signal.SIGTERM: 'SIGTERM',
signal.SIGINT: 'SIGINT'}
if _sighup_supported():
signals[signal.SIGHUP] = 'SIGHUP'
return signals[signo]
def _set_signals_handler(handler):
signal.signal(signal.SIGTERM, handler)
signal.signal(signal.SIGINT, handler)
if _sighup_supported():
signal.signal(signal.SIGHUP, handler)
class Launcher(object):
"""Launch one or more services and wait for them to complete."""
def __init__(self):
"""Initialize the service launcher.
:returns: None
"""
self.services = Services()
self.backdoor_port = eventlet_backdoor.initialize_if_enabled()
def launch_service(self, service):
"""Load and start the given service.
:param service: The service you would like to start.
:returns: None
"""
service.backdoor_port = self.backdoor_port
self.services.add(service)
def stop(self):
"""Stop all services which are currently running.
:returns: None
"""
self.services.stop()
def wait(self):
"""Waits until all services have been stopped, and then returns.
:returns: None
"""
self.services.wait()
def restart(self):
"""Reload config files and restart service.
:returns: None
"""
cfg.CONF.reload_config_files()
self.services.restart()
class SignalExit(SystemExit):
def __init__(self, signo, exccode=1):
super(SignalExit, self).__init__(exccode)
self.signo = signo
class ServiceLauncher(Launcher):
def _handle_signal(self, signo, frame):
# Allow the process to be killed again and die from natural causes
_set_signals_handler(signal.SIG_DFL)
raise SignalExit(signo)
def handle_signal(self):
_set_signals_handler(self._handle_signal)
def _wait_for_exit_or_signal(self, ready_callback=None):
status = None
signo = 0
LOG.debug('Full set of CONF:')
CONF.log_opt_values(LOG, logging.DEBUG)
try:
if ready_callback:
ready_callback()
super(ServiceLauncher, self).wait()
except SignalExit as exc:
signame = _signo_to_signame(exc.signo)
LOG.info(_LI('Caught %s, exiting'), signame)
status = exc.code
signo = exc.signo
except SystemExit as exc:
status = exc.code
finally:
self.stop()
return status, signo
def wait(self, ready_callback=None):
systemd.notify_once()
while True:
self.handle_signal()
status, signo = self._wait_for_exit_or_signal(ready_callback)
if not _is_sighup_and_daemon(signo):
return status
self.restart()
class ServiceWrapper(object):
def __init__(self, service, workers):
self.service = service
self.workers = workers
self.children = set()
self.forktimes = []
class ProcessLauncher(object):
def __init__(self, wait_interval=0.01):
"""Constructor.
:param wait_interval: The interval to sleep for between checks
of child process exit.
"""
self.children = {}
self.sigcaught = None
self.running = True
self.wait_interval = wait_interval
rfd, self.writepipe = os.pipe()
self.readpipe = eventlet.greenio.GreenPipe(rfd, 'r')
self.handle_signal()
def handle_signal(self):
_set_signals_handler(self._handle_signal)
def _handle_signal(self, signo, frame):
self.sigcaught = signo
self.running = False
# Allow the process to be killed again and die from natural causes
_set_signals_handler(signal.SIG_DFL)
def _pipe_watcher(self):
# This will block until the write end is closed when the parent
# dies unexpectedly
self.readpipe.read()
LOG.info(_LI('Parent process has died unexpectedly, exiting'))
sys.exit(1)
def _child_process_handle_signal(self):
# Setup child signal handlers differently
def _sigterm(*args):
signal.signal(signal.SIGTERM, signal.SIG_DFL)
raise SignalExit(signal.SIGTERM)
def _sighup(*args):
signal.signal(signal.SIGHUP, signal.SIG_DFL)
raise SignalExit(signal.SIGHUP)
signal.signal(signal.SIGTERM, _sigterm)
if _sighup_supported():
signal.signal(signal.SIGHUP, _sighup)
# Block SIGINT and let the parent send us a SIGTERM
signal.signal(signal.SIGINT, signal.SIG_IGN)
def _child_wait_for_exit_or_signal(self, launcher):
status = 0
signo = 0
# NOTE(johannes): All exceptions are caught to ensure this
# doesn't fallback into the loop spawning children. It would
# be bad for a child to spawn more children.
try:
launcher.wait()
except SignalExit as exc:
signame = _signo_to_signame(exc.signo)
LOG.info(_LI('Child caught %s, exiting'), signame)
status = exc.code
signo = exc.signo
except SystemExit as exc:
status = exc.code
except BaseException:
LOG.exception(_LE('Unhandled exception'))
status = 2
finally:
launcher.stop()
return status, signo
def _child_process(self, service):
self._child_process_handle_signal()
# Reopen the eventlet hub to make sure we don't share an epoll
# fd with parent and/or siblings, which would be bad
eventlet.hubs.use_hub()
# Close write to ensure only parent has it open
os.close(self.writepipe)
# Create greenthread to watch for parent to close pipe
eventlet.spawn_n(self._pipe_watcher)
# Reseed random number generator
random.seed()
launcher = Launcher()
launcher.launch_service(service)
return launcher
def _start_child(self, wrap):
if len(wrap.forktimes) > wrap.workers:
# Limit ourselves to one process a second (over the period of
# number of workers * 1 second). This will allow workers to
# start up quickly but ensure we don't fork off children that
# die instantly too quickly.
if time.time() - wrap.forktimes[0] < wrap.workers:
LOG.info(_LI('Forking too fast, sleeping'))
time.sleep(1)
wrap.forktimes.pop(0)
wrap.forktimes.append(time.time())
pid = os.fork()
if pid == 0:
launcher = self._child_process(wrap.service)
while True:
self._child_process_handle_signal()
status, signo = self._child_wait_for_exit_or_signal(launcher)
if not _is_sighup_and_daemon(signo):
break
launcher.restart()
os._exit(status)
LOG.info(_LI('Started child %d'), pid)
wrap.children.add(pid)
self.children[pid] = wrap
return pid
def launch_service(self, service, workers=1):
wrap = ServiceWrapper(service, workers)
LOG.info(_LI('Starting %d workers'), wrap.workers)
while self.running and len(wrap.children) < wrap.workers:
self._start_child(wrap)
def _wait_child(self):
try:
# Don't block if no child processes have exited
pid, status = os.waitpid(0, os.WNOHANG)
if not pid:
return None
except OSError as exc:
if exc.errno not in (errno.EINTR, errno.ECHILD):
raise
return None
if os.WIFSIGNALED(status):
sig = os.WTERMSIG(status)
LOG.info(_LI('Child %(pid)d killed by signal %(sig)d'),
dict(pid=pid, sig=sig))
else:
code = os.WEXITSTATUS(status)
LOG.info(_LI('Child %(pid)s exited with status %(code)d'),
dict(pid=pid, code=code))
if pid not in self.children:
LOG.warning(_LW('pid %d not in child list'), pid)
return None
wrap = self.children.pop(pid)
wrap.children.remove(pid)
return wrap
def _respawn_children(self):
while self.running:
wrap = self._wait_child()
if not wrap:
# Yield to other threads if no children have exited
# Sleep for a short time to avoid excessive CPU usage
# (see bug #1095346)
eventlet.greenthread.sleep(self.wait_interval)
continue
while self.running and len(wrap.children) < wrap.workers:
self._start_child(wrap)
def wait(self):
"""Loop waiting on children to die and respawning as necessary."""
systemd.notify_once()
LOG.debug('Full set of CONF:')
CONF.log_opt_values(LOG, logging.DEBUG)
try:
while True:
self.handle_signal()
self._respawn_children()
# No signal means that stop was called. Don't clean up here.
if not self.sigcaught:
return
signame = _signo_to_signame(self.sigcaught)
LOG.info(_LI('Caught %s, stopping children'), signame)
if not _is_sighup_and_daemon(self.sigcaught):
break
for pid in self.children:
os.kill(pid, signal.SIGHUP)
self.running = True
self.sigcaught = None
except eventlet.greenlet.GreenletExit:
LOG.info(_LI("Wait called after thread killed. Cleaning up."))
self.stop()
def stop(self):
"""Terminate child processes and wait on each."""
self.running = False
for pid in self.children:
try:
os.kill(pid, signal.SIGTERM)
except OSError as exc:
if exc.errno != errno.ESRCH:
raise
# Wait for children to die
if self.children:
LOG.info(_LI('Waiting on %d children to exit'), len(self.children))
while self.children:
self._wait_child()
class Service(object):
"""Service object for binaries running on hosts."""
def __init__(self, threads=1000):
self.tg = threadgroup.ThreadGroup(threads)
# signal that the service is done shutting itself down:
self._done = event.Event()
def reset(self):
# NOTE(Fengqian): docs for Event.reset() recommend against using it
self._done = event.Event()
def start(self):
pass
def stop(self, graceful=False):
self.tg.stop(graceful)
self.tg.wait()
# Signal that service cleanup is done:
if not self._done.ready():
self._done.send()
def wait(self):
self._done.wait()
class Services(object):
def __init__(self):
self.services = []
self.tg = threadgroup.ThreadGroup()
self.done = event.Event()
def add(self, service):
self.services.append(service)
self.tg.add_thread(self.run_service, service, self.done)
def stop(self):
# wait for graceful shutdown of services:
for service in self.services:
service.stop()
service.wait()
# Each service has performed cleanup, now signal that the run_service
# wrapper threads can now die:
if not self.done.ready():
self.done.send()
# reap threads:
self.tg.stop()
def wait(self):
self.tg.wait()
def restart(self):
self.stop()
self.done = event.Event()
for restart_service in self.services:
restart_service.reset()
self.tg.add_thread(self.run_service, restart_service, self.done)
@staticmethod
def run_service(service, done):
"""Service start wrapper.
:param service: service to run
:param done: event to wait on until a shutdown is triggered
:returns: None
"""
service.start()
done.wait()
def launch(service, workers=1):
if workers is None or workers == 1:
launcher = ServiceLauncher()
launcher.launch_service(service)
else:
launcher = ProcessLauncher()
launcher.launch_service(service, workers=workers)
return launcher

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# Copyright 2012-2014 Red Hat, Inc.
#
# 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.
"""
Helper module for systemd service readiness notification.
"""
import logging
import os
import socket
import sys
LOG = logging.getLogger(__name__)
def _abstractify(socket_name):
if socket_name.startswith('@'):
# abstract namespace socket
socket_name = '\0%s' % socket_name[1:]
return socket_name
def _sd_notify(unset_env, msg):
notify_socket = os.getenv('NOTIFY_SOCKET')
if notify_socket:
sock = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
try:
sock.connect(_abstractify(notify_socket))
sock.sendall(msg)
if unset_env:
del os.environ['NOTIFY_SOCKET']
except EnvironmentError:
LOG.debug("Systemd notification failed", exc_info=True)
finally:
sock.close()
def notify():
"""Send notification to Systemd that service is ready.
For details see
http://www.freedesktop.org/software/systemd/man/sd_notify.html
"""
_sd_notify(False, 'READY=1')
def notify_once():
"""Send notification once to Systemd that service is ready.
Systemd sets NOTIFY_SOCKET environment variable with the name of the
socket listening for notifications from services.
This method removes the NOTIFY_SOCKET environment variable to ensure
notification is sent only once.
"""
_sd_notify(True, 'READY=1')
def onready(notify_socket, timeout):
"""Wait for systemd style notification on the socket.
:param notify_socket: local socket address
:type notify_socket: string
:param timeout: socket timeout
:type timeout: float
:returns: 0 service ready
1 service not ready
2 timeout occurred
"""
sock = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
sock.settimeout(timeout)
sock.bind(_abstractify(notify_socket))
try:
msg = sock.recv(512)
except socket.timeout:
return 2
finally:
sock.close()
if 'READY=1' in msg:
return 0
else:
return 1
if __name__ == '__main__':
# simple CLI for testing
if len(sys.argv) == 1:
notify()
elif len(sys.argv) >= 2:
timeout = float(sys.argv[1])
notify_socket = os.getenv('NOTIFY_SOCKET')
if notify_socket:
retval = onready(notify_socket, timeout)
sys.exit(retval)

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# Copyright 2012 Red Hat, Inc.
#
# 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 logging
import threading
import eventlet
from eventlet import greenpool
from glance.openstack.common import loopingcall
LOG = logging.getLogger(__name__)
def _thread_done(gt, *args, **kwargs):
"""Callback function to be passed to GreenThread.link() when we spawn()
Calls the :class:`ThreadGroup` to notify if.
"""
kwargs['group'].thread_done(kwargs['thread'])
class Thread(object):
"""Wrapper around a greenthread, that holds a reference to the
:class:`ThreadGroup`. The Thread will notify the :class:`ThreadGroup` when
it has done so it can be removed from the threads list.
"""
def __init__(self, thread, group):
self.thread = thread
self.thread.link(_thread_done, group=group, thread=self)
def stop(self):
self.thread.kill()
def wait(self):
return self.thread.wait()
def link(self, func, *args, **kwargs):
self.thread.link(func, *args, **kwargs)
class ThreadGroup(object):
"""The point of the ThreadGroup class is to:
* keep track of timers and greenthreads (making it easier to stop them
when need be).
* provide an easy API to add timers.
"""
def __init__(self, thread_pool_size=10):
self.pool = greenpool.GreenPool(thread_pool_size)
self.threads = []
self.timers = []
def add_dynamic_timer(self, callback, initial_delay=None,
periodic_interval_max=None, *args, **kwargs):
timer = loopingcall.DynamicLoopingCall(callback, *args, **kwargs)
timer.start(initial_delay=initial_delay,
periodic_interval_max=periodic_interval_max)
self.timers.append(timer)
def add_timer(self, interval, callback, initial_delay=None,
*args, **kwargs):
pulse = loopingcall.FixedIntervalLoopingCall(callback, *args, **kwargs)
pulse.start(interval=interval,
initial_delay=initial_delay)
self.timers.append(pulse)
def add_thread(self, callback, *args, **kwargs):
gt = self.pool.spawn(callback, *args, **kwargs)
th = Thread(gt, self)
self.threads.append(th)
return th
def thread_done(self, thread):
self.threads.remove(thread)
def _stop_threads(self):
current = threading.current_thread()
# Iterate over a copy of self.threads so thread_done doesn't
# modify the list while we're iterating
for x in self.threads[:]:
if x is current:
# don't kill the current thread.
continue
try:
x.stop()
except eventlet.greenlet.GreenletExit:
pass
except Exception as ex:
LOG.exception(ex)
def stop_timers(self):
for x in self.timers:
try:
x.stop()
except Exception as ex:
LOG.exception(ex)
self.timers = []
def stop(self, graceful=False):
"""stop function has the option of graceful=True/False.
* In case of graceful=True, wait for all threads to be finished.
Never kill threads.
* In case of graceful=False, kill threads immediately.
"""
self.stop_timers()
if graceful:
# In case of graceful=True, wait for all threads to be
# finished, never kill threads
self.wait()
else:
# In case of graceful=False(Default), kill threads
# immediately
self._stop_threads()
def wait(self):
for x in self.timers:
try:
x.wait()
except eventlet.greenlet.GreenletExit:
pass
except Exception as ex:
LOG.exception(ex)
current = threading.current_thread()
# Iterate over a copy of self.threads so thread_done doesn't
# modify the list while we're iterating
for x in self.threads[:]:
if x is current:
continue
try:
x.wait()
except eventlet.greenlet.GreenletExit:
pass
except Exception as ex:
LOG.exception(ex)

View File

@ -4,6 +4,7 @@
module=install_venv_common
module=log
module=policy
module=service
# The base module to hold the copy of openstack.common
base=glance