ceilometer/ceilometer/messaging.py

90 lines
3.3 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2013-2015 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
import oslo_messaging
from oslo_messaging._drivers import impl_rabbit
from oslo_messaging.notify import notifier
from oslo_messaging import serializer as oslo_serializer
DEFAULT_URL = "__default__"
TRANSPORTS = {}
def setup():
oslo_messaging.set_transport_defaults('ceilometer')
# NOTE(sileht): When batch is not enabled, oslo.messaging read all messages
# in the queue and can consume a lot of memory, that works for rpc because
# you never have a lot of message, but sucks for notification. The
# default is not changeable on oslo.messaging side. And we can't expose
# this option to set set_transport_defaults because it a driver option.
# 100 allow to prefetch a lot of messages but limit memory to 1G per
# workers in worst case (~ 1M Nova notification)
# And even driver options are located in private module, this is not going
# to break soon.
cfg.set_defaults(
impl_rabbit.rabbit_opts,
rabbit_qos_prefetch_count=100,
)
def get_transport(conf, 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 = notifier.get_notification_transport(conf, url)
except (oslo_messaging.InvalidTransportURL,
oslo_messaging.DriverLoadFailure):
if not optional or 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]
_SERIALIZER = oslo_serializer.JsonPayloadSerializer()
def get_batch_notification_listener(transport, targets, endpoints,
allow_requeue=False,
batch_size=1, batch_timeout=None):
"""Return a configured oslo_messaging notification listener."""
return oslo_messaging.get_batch_notification_listener(
transport, targets, endpoints, executor='threading',
allow_requeue=allow_requeue,
batch_size=batch_size, batch_timeout=batch_timeout)
def get_notifier(transport, publisher_id):
"""Return a configured oslo_messaging notifier."""
notifier = oslo_messaging.Notifier(transport, serializer=_SERIALIZER)
return notifier.prepare(publisher_id=publisher_id)