murano/murano/engine/system/agent_listener.py

109 lines
3.6 KiB
Python

# Copyright (c) 2013 Mirantis 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 greenlet
from oslo_config import cfg
from oslo_log import log as logging
from murano.common import exceptions
from murano.dsl import dsl
from murano.engine.system import common
LOG = logging.getLogger(__name__)
CONF = cfg.CONF
class AgentListenerException(Exception):
pass
@dsl.name('io.murano.system.AgentListener')
class AgentListener(object):
def __init__(self, name):
self._enabled = not CONF.engine.disable_murano_agent
self._results_queue = str('-execution-results-%s' % name.lower())
self._subscriptions = {}
self._receive_thread = None
def _check_enabled(self):
if CONF.engine.disable_murano_agent:
LOG.error('Use of murano-agent is disallowed '
'by the server configuration')
raise exceptions.PolicyViolationException(
'Use of murano-agent is disallowed '
'by the server configuration')
@property
def enabled(self):
return self._enabled
def queue_name(self):
return self._results_queue
def start(self):
if CONF.engine.disable_murano_agent:
# Noop
LOG.debug("murano-agent is disabled by the server")
return
if self._receive_thread is None:
dsl.get_execution_session().on_session_finish(
lambda: self.stop())
self._receive_thread = dsl.spawn(
self._receive,
dsl.get_this().find_owner('io.murano.CloudRegion'))
def stop(self):
if CONF.engine.disable_murano_agent:
# Noop
LOG.debug("murano-agent is disabled by the server")
return
if self._receive_thread is not None:
self._receive_thread.kill()
try:
self._receive_thread.wait()
except greenlet.GreenletExit:
pass
finally:
self._receive_thread = None
def subscribe(self, message_id, event):
self._check_enabled()
self._subscriptions[message_id] = event
self.start()
def unsubscribe(self, message_id):
self._check_enabled()
self._subscriptions.pop(message_id)
def _receive(self, region):
with common.create_rmq_client(region) as client:
client.declare(self._results_queue, enable_ha=True, ttl=86400000)
with client.open(self._results_queue) as subscription:
while True:
msg = subscription.get_message()
if not msg:
continue
msg.ack()
msg_id = msg.body.get('SourceID', msg.id)
LOG.debug("Got execution result: id '{msg_id}'"
" body '{body}'".format(msg_id=msg_id,
body=msg.body))
if msg_id in self._subscriptions:
event = self._subscriptions.pop(msg_id)
event.send(msg.body)