cinder/cinder/service.py

409 lines
15 KiB
Python
Executable File

# 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 inspect
import os
import random
from oslo.config import cfg
from oslo import messaging
from cinder import context
from cinder import db
from cinder import exception
from cinder.openstack.common import importutils
from cinder.openstack.common import log as logging
from cinder.openstack.common import loopingcall
from cinder.openstack.common import service
from cinder import rpc
from cinder import version
from cinder import wsgi
LOG = logging.getLogger(__name__)
service_opts = [
cfg.IntOpt('report_interval',
default=10,
help='seconds between nodes reporting state to datastore'),
cfg.IntOpt('periodic_interval',
default=60,
help='seconds between running periodic tasks'),
cfg.IntOpt('periodic_fuzzy_delay',
default=60,
help='range of seconds to randomly delay when starting the'
' periodic task scheduler to reduce stampeding.'
' (Disable by setting to 0)'),
cfg.StrOpt('osapi_volume_listen',
default="0.0.0.0",
help='IP address for OpenStack Volume API to listen'),
cfg.IntOpt('osapi_volume_listen_port',
default=8776,
help='port for os volume api to listen'),
cfg.IntOpt('osapi_volume_workers',
help='Number of workers for OpenStack Volume API service'), ]
CONF = cfg.CONF
CONF.register_opts(service_opts)
class Service(service.Service):
"""Service object for binaries running on hosts.
A service takes a manager and enables rpc by listening to queues based
on topic. It also periodically runs tasks on the manager and reports
it state to the database services table.
"""
def __init__(self, host, binary, topic, manager, report_interval=None,
periodic_interval=None, periodic_fuzzy_delay=None,
service_name=None, *args, **kwargs):
super(Service, self).__init__()
if not rpc.initialized():
rpc.init(CONF)
self.host = host
self.binary = binary
self.topic = topic
self.manager_class_name = manager
manager_class = importutils.import_class(self.manager_class_name)
self.manager = manager_class(host=self.host,
service_name=service_name,
*args, **kwargs)
self.report_interval = report_interval
self.periodic_interval = periodic_interval
self.periodic_fuzzy_delay = periodic_fuzzy_delay
self.basic_config_check()
self.saved_args, self.saved_kwargs = args, kwargs
self.timers = []
def start(self):
version_string = version.version_string()
LOG.audit(_('Starting %(topic)s node (version %(version_string)s)'),
{'topic': self.topic, 'version_string': version_string})
self.model_disconnected = False
ctxt = context.get_admin_context()
try:
service_ref = db.service_get_by_args(ctxt,
self.host,
self.binary)
self.service_id = service_ref['id']
except exception.NotFound:
self._create_service_ref(ctxt)
LOG.debug(_("Creating RPC server for service %s") % self.topic)
target = messaging.Target(topic=self.topic, server=self.host)
endpoints = [self.manager]
endpoints.extend(self.manager.additional_endpoints)
self.rpcserver = rpc.get_server(target, endpoints)
self.rpcserver.start()
self.manager.init_host()
if self.report_interval:
pulse = loopingcall.LoopingCall(self.report_state)
pulse.start(interval=self.report_interval,
initial_delay=self.report_interval)
self.timers.append(pulse)
if self.periodic_interval:
if self.periodic_fuzzy_delay:
initial_delay = random.randint(0, self.periodic_fuzzy_delay)
else:
initial_delay = None
periodic = loopingcall.LoopingCall(self.periodic_tasks)
periodic.start(interval=self.periodic_interval,
initial_delay=initial_delay)
self.timers.append(periodic)
def basic_config_check(self):
"""Perform basic config checks before starting service."""
# Make sure report interval is less than service down time
if self.report_interval:
if CONF.service_down_time <= self.report_interval:
new_down_time = int(self.report_interval * 2.5)
LOG.warn(_("Report interval must be less than service down "
"time. Current config service_down_time: "
"%(service_down_time)s, report_interval for this: "
"service is: %(report_interval)s. Setting global "
"service_down_time to: %(new_down_time)s") %
{'service_down_time': CONF.service_down_time,
'report_interval': self.report_interval,
'new_down_time': new_down_time})
CONF.set_override('service_down_time', new_down_time)
def _create_service_ref(self, context):
zone = CONF.storage_availability_zone
service_ref = db.service_create(context,
{'host': self.host,
'binary': self.binary,
'topic': self.topic,
'report_count': 0,
'availability_zone': zone})
self.service_id = service_ref['id']
def __getattr__(self, key):
manager = self.__dict__.get('manager', None)
return getattr(manager, key)
@classmethod
def create(cls, host=None, binary=None, topic=None, manager=None,
report_interval=None, periodic_interval=None,
periodic_fuzzy_delay=None, service_name=None):
"""Instantiates class and passes back application object.
:param host: defaults to CONF.host
:param binary: defaults to basename of executable
:param topic: defaults to bin_name - 'cinder-' part
:param manager: defaults to CONF.<topic>_manager
:param report_interval: defaults to CONF.report_interval
:param periodic_interval: defaults to CONF.periodic_interval
:param periodic_fuzzy_delay: defaults to CONF.periodic_fuzzy_delay
"""
if not host:
host = CONF.host
if not binary:
binary = os.path.basename(inspect.stack()[-1][1])
if not topic:
topic = binary
if not manager:
subtopic = topic.rpartition('cinder-')[2]
manager = CONF.get('%s_manager' % subtopic, None)
if report_interval is None:
report_interval = CONF.report_interval
if periodic_interval is None:
periodic_interval = CONF.periodic_interval
if periodic_fuzzy_delay is None:
periodic_fuzzy_delay = CONF.periodic_fuzzy_delay
service_obj = cls(host, binary, topic, manager,
report_interval=report_interval,
periodic_interval=periodic_interval,
periodic_fuzzy_delay=periodic_fuzzy_delay,
service_name=service_name)
return service_obj
def kill(self):
"""Destroy the service object in the datastore."""
self.stop()
try:
db.service_destroy(context.get_admin_context(), self.service_id)
except exception.NotFound:
LOG.warn(_('Service killed that has no database entry'))
def stop(self):
# Try to shut the connection down, but if we get any sort of
# errors, go ahead and ignore them.. as we're shutting down anyway
try:
self.rpcserver.stop()
except Exception:
pass
for x in self.timers:
try:
x.stop()
except Exception:
pass
self.timers = []
super(Service, self).stop()
def wait(self):
for x in self.timers:
try:
x.wait()
except Exception:
pass
def periodic_tasks(self, raise_on_error=False):
"""Tasks to be run at a periodic interval."""
ctxt = context.get_admin_context()
self.manager.periodic_tasks(ctxt, raise_on_error=raise_on_error)
def report_state(self):
"""Update the state of this service in the datastore."""
ctxt = context.get_admin_context()
zone = CONF.storage_availability_zone
state_catalog = {}
try:
try:
service_ref = db.service_get(ctxt, self.service_id)
except exception.NotFound:
LOG.debug(_('The service database object disappeared, '
'Recreating it.'))
self._create_service_ref(ctxt)
service_ref = db.service_get(ctxt, self.service_id)
state_catalog['report_count'] = service_ref['report_count'] + 1
if zone != service_ref['availability_zone']:
state_catalog['availability_zone'] = zone
db.service_update(ctxt,
self.service_id, state_catalog)
# TODO(termie): make this pattern be more elegant.
if getattr(self, 'model_disconnected', False):
self.model_disconnected = False
LOG.error(_('Recovered model server connection!'))
# TODO(vish): this should probably only catch connection errors
except Exception: # pylint: disable=W0702
if not getattr(self, 'model_disconnected', False):
self.model_disconnected = True
LOG.exception(_('model server went away'))
class WSGIService(object):
"""Provides ability to launch API from a 'paste' configuration."""
def __init__(self, name, loader=None):
"""Initialize, but do not start the WSGI server.
:param name: The name of the WSGI server given to the loader.
:param loader: Loads the WSGI application using the given name.
:returns: None
"""
self.name = name
self.manager = self._get_manager()
self.loader = loader or wsgi.Loader()
self.app = self.loader.load_app(name)
self.host = getattr(CONF, '%s_listen' % name, "0.0.0.0")
self.port = getattr(CONF, '%s_listen_port' % name, 0)
self.workers = getattr(CONF, '%s_workers' % name, None)
if self.workers < 1:
LOG.warn(_("Value of config option %(name)s_workers must be "
"integer greater than 1. Input value ignored.") %
{'name': name})
# Reset workers to default
self.workers = None
self.server = wsgi.Server(name,
self.app,
host=self.host,
port=self.port)
def _get_manager(self):
"""Initialize a Manager object appropriate for this service.
Use the service name to look up a Manager subclass from the
configuration and initialize an instance. If no class name
is configured, just return None.
:returns: a Manager instance, or None.
"""
fl = '%s_manager' % self.name
if fl not in CONF:
return None
manager_class_name = CONF.get(fl, None)
if not manager_class_name:
return None
manager_class = importutils.import_class(manager_class_name)
return manager_class()
def start(self):
"""Start serving this service using loaded configuration.
Also, retrieve updated port number in case '0' was passed in, which
indicates a random port should be used.
:returns: None
"""
if self.manager:
self.manager.init_host()
self.server.start()
self.port = self.server.port
def stop(self):
"""Stop serving this API.
:returns: None
"""
self.server.stop()
def wait(self):
"""Wait for the service to stop serving this API.
:returns: None
"""
self.server.wait()
def process_launcher():
return service.ProcessLauncher()
# NOTE(vish): the global launcher is to maintain the existing
# functionality of calling service.serve +
# service.wait
_launcher = None
def serve(server, workers=None):
global _launcher
if _launcher:
raise RuntimeError(_('serve() can only be called once'))
_launcher = service.launch(server, workers=workers)
def wait():
LOG.debug(_('Full set of CONF:'))
for flag in CONF:
flag_get = CONF.get(flag, None)
# hide flag contents from log if contains a password
# should use secret flag when switch over to openstack-common
if ("_password" in flag or "_key" in flag or
(flag == "sql_connection" and
("mysql:" in flag_get or "postgresql:" in flag_get))):
LOG.debug(_('%s : FLAG SET ') % flag)
else:
LOG.debug('%(flag)s : %(flag_get)s' %
{'flag': flag, 'flag_get': flag_get})
try:
_launcher.wait()
except KeyboardInterrupt:
_launcher.stop()
rpc.cleanup()
class Launcher(object):
def __init__(self):
self.launch_service = serve
self.wait = wait
def get_launcher():
# Note(lpetrut): ProcessLauncher uses green pipes which fail on Windows
# due to missing support of non-blocking I/O pipes. For this reason, the
# service must be spawned differently on Windows, using the ServiceLauncher
# class instead.
if os.name == 'nt':
return Launcher()
else:
return process_launcher()