aodh/aodh/messaging.py

119 lines
4.0 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2013 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.
from oslo_config import cfg
from oslo_context import context
import oslo_messaging
from oslo_serialization import jsonutils
DEFAULT_URL = "__default__"
TRANSPORTS = {}
class RequestContextSerializer(oslo_messaging.Serializer):
def __init__(self, base):
self._base = base
def serialize_entity(self, ctxt, entity):
if not self._base:
return entity
return self._base.serialize_entity(ctxt, entity)
def deserialize_entity(self, ctxt, entity):
if not self._base:
return entity
return self._base.deserialize_entity(ctxt, entity)
@staticmethod
def serialize_context(ctxt):
return ctxt.to_dict()
@staticmethod
def deserialize_context(ctxt):
return context.RequestContext(ctxt)
class JsonPayloadSerializer(oslo_messaging.NoOpSerializer):
@classmethod
def serialize_entity(cls, context, entity):
return jsonutils.to_primitive(entity, convert_instances=True)
def setup():
oslo_messaging.set_transport_defaults('aodh')
def get_transport(url=None, optional=False, cache=True):
"""Initialise the oslo_messaging layer."""
global TRANSPORTS, DEFAULT_URL
cache_key = url or DEFAULT_URL
transport = TRANSPORTS.get(cache_key)
if not transport or not cache:
try:
transport = oslo_messaging.get_transport(cfg.CONF, url)
except oslo_messaging.InvalidTransportURL as e:
if not optional or e.url:
# NOTE(sileht): oslo_messaging is configured but unloadable
# so reraise the exception
raise
return None
else:
if cache:
TRANSPORTS[cache_key] = transport
return transport
def cleanup():
"""Cleanup the oslo_messaging layer."""
global TRANSPORTS, NOTIFIERS
NOTIFIERS = {}
for url in TRANSPORTS:
TRANSPORTS[url].cleanup()
del TRANSPORTS[url]
def get_rpc_server(transport, topic, endpoint):
"""Return a configured oslo_messaging rpc server."""
cfg.CONF.import_opt('host', 'aodh.service')
target = oslo_messaging.Target(server=cfg.CONF.host, topic=topic)
serializer = RequestContextSerializer(JsonPayloadSerializer())
return oslo_messaging.get_rpc_server(transport, target,
[endpoint], executor='eventlet',
serializer=serializer)
def get_rpc_client(transport, retry=None, **kwargs):
"""Return a configured oslo_messaging RPCClient."""
target = oslo_messaging.Target(**kwargs)
serializer = RequestContextSerializer(JsonPayloadSerializer())
return oslo_messaging.RPCClient(transport, target,
serializer=serializer,
retry=retry)
def get_notification_listener(transport, targets, endpoints,
allow_requeue=False):
"""Return a configured oslo_messaging notification listener."""
return oslo_messaging.get_notification_listener(
transport, targets, endpoints, executor='eventlet',
allow_requeue=allow_requeue)
def get_notifier(transport, publisher_id):
"""Return a configured oslo_messaging notifier."""
serializer = RequestContextSerializer(JsonPayloadSerializer())
notifier = oslo_messaging.Notifier(transport, serializer=serializer)
return notifier.prepare(publisher_id=publisher_id)