openstack/neutron
Code Issues Proposed changes

Sync service and systemd modules from oslo-incubator

Browse Source 
This patch make systemd know when neutron-service was started. This is
needed in HA environment, previously systemd returned success even
before neutron-server was able to handle requests.

Current oslo-incubator commit on HEAD:
b7ad6ddab8b1d61bf4f52ccaa461a9d68809747b

Implements: blueprint service-readiness
Change-Id: Ic9e4abd11b614a896fbd7454b9a604a69a248d0f
This commit is contained in:
Jakub Libosvar 2014-03-17 16:36:01 +01:00
parent db232425e6
commit 149679b2dc
3 changed files with 143 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
neutron/openstack/common/service.py
View File

@ -38,9 +38,10 @@ from eventlet import event
from oslo.config import cfg
from neutron.openstack.common import eventlet_backdoor
from neutron.openstack.common.gettextutils import _
from neutron.openstack.common.gettextutils import _LE, _LI, _LW
from neutron.openstack.common import importutils
from neutron.openstack.common import log as logging
from neutron.openstack.common import systemd
from neutron.openstack.common import threadgroup
@ -163,7 +164,7 @@ class ServiceLauncher(Launcher):
status = None
signo = 0
LOG.debug(_('Full set of CONF:'))
LOG.debug('Full set of CONF:')
CONF.log_opt_values(LOG, std_logging.DEBUG)
try:
@ -172,7 +173,7 @@ class ServiceLauncher(Launcher):
super(ServiceLauncher, self).wait()
except SignalExit as exc:
signame = _signo_to_signame(exc.signo)
LOG.info(_('Caught %s, exiting'), signame)
LOG.info(_LI('Caught %s, exiting'), signame)
status = exc.code
signo = exc.signo
except SystemExit as exc:
@ -184,7 +185,7 @@ class ServiceLauncher(Launcher):
rpc.cleanup()
except Exception:
# We're shutting down, so it doesn't matter at this point.
LOG.exception(_('Exception during rpc cleanup.'))
LOG.exception(_LE('Exception during rpc cleanup.'))
return status, signo
@ -235,7 +236,7 @@ class ProcessLauncher(object):
# dies unexpectedly
self.readpipe.read()
LOG.info(_('Parent process has died unexpectedly, exiting'))
LOG.info(_LI('Parent process has died unexpectedly, exiting'))
sys.exit(1)
@ -266,13 +267,13 @@ class ProcessLauncher(object):
launcher.wait()
except SignalExit as exc:
signame = _signo_to_signame(exc.signo)
LOG.info(_('Caught %s, exiting'), signame)
LOG.info(_LI('Caught %s, exiting'), signame)
status = exc.code
signo = exc.signo
except SystemExit as exc:
status = exc.code
except BaseException:
LOG.exception(_('Unhandled exception'))
LOG.exception(_LE('Unhandled exception'))
status = 2
finally:
launcher.stop()
@ -305,7 +306,7 @@ class ProcessLauncher(object):
# 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(_('Forking too fast, sleeping'))
LOG.info(_LI('Forking too fast, sleeping'))
time.sleep(1)
wrap.forktimes.pop(0)
@ -324,7 +325,7 @@ class ProcessLauncher(object):
os._exit(status)
LOG.info(_('Started child %d'), pid)
LOG.info(_LI('Started child %d'), pid)
wrap.children.add(pid)
self.children[pid] = wrap
@ -334,7 +335,7 @@ class ProcessLauncher(object):
def launch_service(self, service, workers=1):
wrap = ServiceWrapper(service, workers)
LOG.info(_('Starting %d workers'), wrap.workers)
LOG.info(_LI('Starting %d workers'), wrap.workers)
while self.running and len(wrap.children) < wrap.workers:
self._start_child(wrap)
@ -351,15 +352,15 @@ class ProcessLauncher(object):
if os.WIFSIGNALED(status):
sig = os.WTERMSIG(status)
LOG.info(_('Child %(pid)d killed by signal %(sig)d'),
LOG.info(_LI('Child %(pid)d killed by signal %(sig)d'),
dict(pid=pid, sig=sig))
else:
code = os.WEXITSTATUS(status)
LOG.info(_('Child %(pid)s exited with status %(code)d'),
LOG.info(_LI('Child %(pid)s exited with status %(code)d'),
dict(pid=pid, code=code))
if pid not in self.children:
LOG.warning(_('pid %d not in child list'), pid)
LOG.warning(_LW('pid %d not in child list'), pid)
return None
wrap = self.children.pop(pid)
@ -381,22 +382,25 @@ class ProcessLauncher(object):
def wait(self):
"""Loop waiting on children to die and respawning as necessary."""
LOG.debug(_('Full set of CONF:'))
LOG.debug('Full set of CONF:')
CONF.log_opt_values(LOG, std_logging.DEBUG)
while True:
self.handle_signal()
self._respawn_children()
if self.sigcaught:
signame = _signo_to_signame(self.sigcaught)
LOG.info(_('Caught %s, stopping children'), signame)
if not _is_sighup_and_daemon(self.sigcaught):
break
try:
while True:
self.handle_signal()
self._respawn_children()
if self.sigcaught:
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
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."))
for pid in self.children:
try:
@ -407,7 +411,7 @@ class ProcessLauncher(object):
# Wait for children to die
if self.children:
LOG.info(_('Waiting on %d children to exit'), len(self.children))
LOG.info(_LI('Waiting on %d children to exit'), len(self.children))
while self.children:
self._wait_child()
@ -484,14 +488,16 @@ class Services(object):
"""
service.start()
systemd.notify_once()
done.wait()
def launch(service, workers=None):
if workers:
launcher = ProcessLauncher()
launcher.launch_service(service, workers=workers)
else:
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

104
neutron/openstack/common/systemd.py Normal file
View File

@ -0,0 +1,104 @@
# 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 os
import socket
import sys
from neutron.openstack.common import log as logging
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 occured
"""
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)

1
openstack-common.conf
View File

@ -26,6 +26,7 @@ module=processutils
module=rpc
module=service
module=sslutils
module=systemd
module=threadgroup
module=timeutils
module=uuidutils