Source code for watcher.common.service

# -*- encoding: utf-8 -*-
#
# Copyright © 2012 eNovance <licensing@enovance.com>
##
# 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 datetime
import socket

import eventlet
from oslo_concurrency import processutils
from oslo_config import cfg
from oslo_log import _options
from oslo_log import log
import oslo_messaging as om
from oslo_reports import guru_meditation_report as gmr
from oslo_reports import opts as gmr_opts
from oslo_service import service
from oslo_service import wsgi

from watcher._i18n import _
from watcher.api import app
from watcher.common import config
from watcher.common import context
from watcher.common import rpc
from watcher.common import scheduling
from watcher.conf import plugins as plugins_conf
from watcher import objects
from watcher.objects import base
from watcher.objects import fields as wfields
from watcher import version

# NOTE:
# Ubuntu 14.04 forces librabbitmq when kombu is used
# Unfortunately it forces a version that has a crash
# bug.  Calling eventlet.monkey_patch() tells kombu
# to use libamqp instead.
eventlet.monkey_patch()

NOTIFICATION_OPTS = [
    cfg.StrOpt('notification_level',
               choices=[''] + list(wfields.NotificationPriority.ALL),
               default=wfields.NotificationPriority.INFO,
               help=_('Specifies the minimum level for which to send '
                      'notifications. If not set, no notifications will '
                      'be sent. The default is for this option to be at the '
                      '`INFO` level.'))
]
cfg.CONF.register_opts(NOTIFICATION_OPTS)


CONF = cfg.CONF
LOG = log.getLogger(__name__)

_DEFAULT_LOG_LEVELS = ['amqp=WARN', 'amqplib=WARN', 'qpid.messaging=INFO',
                       'oslo.messaging=INFO', 'sqlalchemy=WARN',
                       'keystoneclient=INFO', 'stevedore=INFO',
                       'eventlet.wsgi.server=WARN', 'iso8601=WARN',
                       'paramiko=WARN', 'requests=WARN', 'neutronclient=WARN',
                       'glanceclient=WARN', 'watcher.openstack.common=WARN']

Singleton = service.Singleton


[docs]class WSGIService(service.ServiceBase): """Provides ability to launch Watcher API from wsgi app.""" def __init__(self, service_name, use_ssl=False): """Initialize, but do not start the WSGI server. :param service_name: The service name of the WSGI server. :param use_ssl: Wraps the socket in an SSL context if True. """ self.service_name = service_name self.app = app.VersionSelectorApplication() self.workers = (CONF.api.workers or processutils.get_worker_count()) self.server = wsgi.Server(CONF, self.service_name, self.app, host=CONF.api.host, port=CONF.api.port, use_ssl=use_ssl, logger_name=self.service_name)
[docs] def start(self): """Start serving this service using loaded configuration""" self.server.start()
[docs] def stop(self): """Stop serving this API""" self.server.stop()
[docs] def wait(self): """Wait for the service to stop serving this API""" self.server.wait()
[docs] def reset(self): """Reset server greenpool size to default""" self.server.reset()
[docs]class ServiceHeartbeat(scheduling.BackgroundSchedulerService): def __init__(self, gconfig=None, service_name=None, **kwargs): gconfig = None or {} super(ServiceHeartbeat, self).__init__(gconfig, **kwargs) self.service_name = service_name self.context = context.make_context()
[docs] def send_beat(self): host = CONF.host watcher_list = objects.Service.list( self.context, filters={'name': self.service_name, 'host': host}) if watcher_list: watcher_service = watcher_list[0] watcher_service.last_seen_up = datetime.datetime.utcnow() watcher_service.save() else: watcher_service = objects.Service(self.context) watcher_service.name = self.service_name watcher_service.host = host watcher_service.create()
[docs] def add_heartbeat_job(self): self.add_job(self.send_beat, 'interval', seconds=60, next_run_time=datetime.datetime.now())
[docs] def start(self): """Start service.""" self.add_heartbeat_job() super(ServiceHeartbeat, self).start()
[docs] def stop(self): """Stop service.""" self.shutdown()
[docs] def wait(self): """Wait for service to complete."""
[docs] def reset(self): """Reset service. Called in case service running in daemon mode receives SIGHUP. """
[docs]class Service(service.ServiceBase): API_VERSION = '1.0' def __init__(self, manager_class): super(Service, self).__init__() self.manager = manager_class() self.publisher_id = self.manager.publisher_id self.api_version = self.manager.api_version self.conductor_topic = self.manager.conductor_topic self.notification_topics = self.manager.notification_topics self.conductor_endpoints = [ ep(self) for ep in self.manager.conductor_endpoints ] self.notification_endpoints = self.manager.notification_endpoints self.serializer = rpc.RequestContextSerializer( base.WatcherObjectSerializer()) self._transport = None self._notification_transport = None self._conductor_client = None self.conductor_topic_handler = None self.notification_handler = None self.heartbeat = None if self.conductor_topic and self.conductor_endpoints: self.conductor_topic_handler = self.build_topic_handler( self.conductor_topic, self.conductor_endpoints) if self.notification_topics and self.notification_endpoints: self.notification_handler = self.build_notification_handler( self.notification_topics, self.notification_endpoints ) self.service_name = self.manager.service_name if self.service_name: self.heartbeat = ServiceHeartbeat( service_name=self.manager.service_name) @property def transport(self): if self._transport is None: self._transport = om.get_transport(CONF) return self._transport @property def notification_transport(self): if self._notification_transport is None: self._notification_transport = om.get_notification_transport(CONF) return self._notification_transport @property def conductor_client(self): if self._conductor_client is None: target = om.Target( topic=self.conductor_topic, version=self.API_VERSION, ) self._conductor_client = om.RPCClient( self.transport, target, serializer=self.serializer) return self._conductor_client @conductor_client.setter def conductor_client(self, c): self.conductor_client = c
[docs] def build_topic_handler(self, topic_name, endpoints=()): serializer = rpc.RequestContextSerializer(rpc.JsonPayloadSerializer()) target = om.Target( topic=topic_name, # For compatibility, we can override it with 'host' opt server=CONF.host or socket.gethostname(), version=self.api_version, ) return om.get_rpc_server( self.transport, target, endpoints, executor='eventlet', serializer=serializer)
[docs] def build_notification_handler(self, topic_names, endpoints=()): serializer = rpc.RequestContextSerializer(rpc.JsonPayloadSerializer()) targets = [om.Target(topic=topic_name) for topic_name in topic_names] return om.get_notification_listener( self.notification_transport, targets, endpoints, executor='eventlet', serializer=serializer, allow_requeue=False)
[docs] def start(self): LOG.debug("Connecting to '%s' (%s)", CONF.transport_url, CONF.rpc_backend) if self.conductor_topic_handler: self.conductor_topic_handler.start() if self.notification_handler: self.notification_handler.start() if self.heartbeat: self.heartbeat.start()
[docs] def stop(self): LOG.debug("Disconnecting from '%s' (%s)", CONF.transport_url, CONF.rpc_backend) if self.conductor_topic_handler: self.conductor_topic_handler.stop() if self.notification_handler: self.notification_handler.stop() if self.heartbeat: self.heartbeat.stop()
[docs] def reset(self): """Reset a service in case it received a SIGHUP."""
[docs] def wait(self): """Wait for service to complete."""
[docs] def check_api_version(self, ctx): api_manager_version = self.conductor_client.call( ctx, 'check_api_version', api_version=self.api_version) return api_manager_version
def launch(conf, service_, workers=1, restart_method='reload'): return service.launch(conf, service_, workers, restart_method) def prepare_service(argv=(), conf=cfg.CONF): log.register_options(conf) gmr_opts.set_defaults(conf) config.parse_args(argv) cfg.set_defaults(_options.log_opts, default_log_levels=_DEFAULT_LOG_LEVELS) log.setup(conf, 'python-watcher') conf.log_opt_values(LOG, log.DEBUG) objects.register_all() gmr.TextGuruMeditation.register_section( _('Plugins'), plugins_conf.show_plugins) gmr.TextGuruMeditation.setup_autorun(version, conf=conf)