105 lines
3.2 KiB
Python
105 lines
3.2 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
#
|
|
# Copyright 2012 New Dream Network, LLC (DreamHost)
|
|
#
|
|
# 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.
|
|
#
|
|
# @author: Mark McClain, DreamHost
|
|
|
|
import os
|
|
|
|
from oslo.config import cfg
|
|
|
|
from neutron.agent.linux import ip_lib
|
|
from neutron.agent.linux import utils
|
|
from neutron.openstack.common import log as logging
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
OPTS = [
|
|
cfg.StrOpt('external_pids',
|
|
default='$state_path/external/pids',
|
|
help=_('Location to store child pid files')),
|
|
]
|
|
|
|
cfg.CONF.register_opts(OPTS)
|
|
|
|
|
|
class ProcessManager(object):
|
|
"""An external process manager for Neutron spawned processes.
|
|
|
|
Note: The manager expects uuid to be in cmdline.
|
|
"""
|
|
def __init__(self, conf, uuid, root_helper='sudo', namespace=None):
|
|
self.conf = conf
|
|
self.uuid = uuid
|
|
self.root_helper = root_helper
|
|
self.namespace = namespace
|
|
|
|
def enable(self, cmd_callback):
|
|
if not self.active:
|
|
cmd = cmd_callback(self.get_pid_file_name(ensure_pids_dir=True))
|
|
|
|
ip_wrapper = ip_lib.IPWrapper(self.root_helper, self.namespace)
|
|
ip_wrapper.netns.execute(cmd)
|
|
|
|
def disable(self):
|
|
pid = self.pid
|
|
|
|
if self.active:
|
|
cmd = ['kill', '-9', pid]
|
|
utils.execute(cmd, self.root_helper)
|
|
elif pid:
|
|
LOG.debug(_('Process for %(uuid)s pid %(pid)d is stale, ignoring '
|
|
'command'), {'uuid': self.uuid, 'pid': pid})
|
|
else:
|
|
LOG.debug(_('No process started for %s'), self.uuid)
|
|
|
|
def get_pid_file_name(self, ensure_pids_dir=False):
|
|
"""Returns the file name for a given kind of config file."""
|
|
pids_dir = os.path.abspath(os.path.normpath(self.conf.external_pids))
|
|
if ensure_pids_dir and not os.path.isdir(pids_dir):
|
|
os.makedirs(pids_dir, 0o755)
|
|
|
|
return os.path.join(pids_dir, self.uuid + '.pid')
|
|
|
|
@property
|
|
def pid(self):
|
|
"""Last known pid for this external process spawned for this uuid."""
|
|
file_name = self.get_pid_file_name()
|
|
msg = _('Error while reading %s')
|
|
|
|
try:
|
|
with open(file_name, 'r') as f:
|
|
return int(f.read())
|
|
except IOError:
|
|
msg = _('Unable to access %s')
|
|
except ValueError:
|
|
msg = _('Unable to convert value in %s')
|
|
|
|
LOG.debug(msg, file_name)
|
|
return None
|
|
|
|
@property
|
|
def active(self):
|
|
pid = self.pid
|
|
if pid is None:
|
|
return False
|
|
|
|
cmdline = '/proc/%s/cmdline' % pid
|
|
try:
|
|
with open(cmdline, "r") as f:
|
|
return self.uuid in f.readline()
|
|
except IOError:
|
|
return False
|