deb-glance/glance/notifier/notify_kombu.py
Eoghan Glynn 35ba3e080b Change type of rabbit_durable_queues to boolean.
Fixes bug 1056465

The rabbit_durable_queues config option should be of type boolean
instead of string, otherwise it does not have the expected effect on
the durability of rabbitmq exchanges and queues.

Change-Id: I9b3dc7d763b109c1bf10f78ebe725d71ed10791a
2012-09-26 07:02:45 +01:00

225 lines
8.3 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2011, OpenStack LLC.
#
# 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 json
import time
import kombu.connection
import kombu.entity
from glance.notifier import strategy
from glance.openstack.common import cfg
import glance.openstack.common.log as logging
LOG = logging.getLogger(__name__)
rabbit_opts = [
cfg.StrOpt('rabbit_host', default='localhost'),
cfg.IntOpt('rabbit_port', default=5672),
cfg.BoolOpt('rabbit_use_ssl', default=False),
cfg.StrOpt('rabbit_userid', default='guest'),
cfg.StrOpt('rabbit_password', default='guest'),
cfg.StrOpt('rabbit_virtual_host', default='/'),
cfg.StrOpt('rabbit_notification_exchange', default='glance'),
cfg.StrOpt('rabbit_notification_topic',
default='glance_notifications'),
cfg.StrOpt('rabbit_max_retries', default=0),
cfg.StrOpt('rabbit_retry_backoff', default=2),
cfg.StrOpt('rabbit_retry_max_backoff', default=30),
cfg.BoolOpt('rabbit_durable_queues', default=False),
]
CONF = cfg.CONF
CONF.register_opts(rabbit_opts)
class KombuMaxRetriesReached(Exception):
pass
class RabbitStrategy(strategy.Strategy):
"""A notifier that puts a message on a queue when called."""
def __init__(self):
"""Initialize the rabbit notification strategy."""
self.topic = CONF.rabbit_notification_topic
self.max_retries = CONF.rabbit_max_retries
# NOTE(comstud): When reading the config file, these values end
# up being strings, and we need them as ints.
self.retry_backoff = int(CONF.rabbit_retry_backoff)
self.retry_max_backoff = int(CONF.rabbit_retry_max_backoff)
self.connection = None
self.retry_attempts = 0
try:
self.reconnect()
except KombuMaxRetriesReached:
pass
def _close(self):
"""Close connection to rabbit."""
try:
self.connection.close()
except self.connection_errors:
pass
self.connection = None
def _connect(self):
"""Connect to rabbit. Exceptions should be handled by the
caller.
"""
log_info = {}
log_info['hostname'] = CONF.rabbit_host
log_info['port'] = CONF.rabbit_port
if self.connection:
LOG.info(_("Reconnecting to AMQP server on "
"%(hostname)s:%(port)d") % log_info)
self._close()
else:
LOG.info(_("Connecting to AMQP server on "
"%(hostname)s:%(port)d") % log_info)
self.connection = kombu.connection.BrokerConnection(
hostname=CONF.rabbit_host,
port=CONF.rabbit_port,
userid=CONF.rabbit_userid,
password=CONF.rabbit_password,
virtual_host=CONF.rabbit_virtual_host,
ssl=CONF.rabbit_use_ssl)
self.connection_errors = self.connection.connection_errors
self.connection.connect()
self.channel = self.connection.channel()
self.exchange = kombu.entity.Exchange(
channel=self.channel,
type="topic",
durable=CONF.rabbit_durable_queues,
name=CONF.rabbit_notification_exchange)
# NOTE(jerdfelt): Normally the consumer would create the queues,
# but we do this to ensure that messages don't get dropped if the
# consumer is started after we do
for priority in ["WARN", "INFO", "ERROR"]:
routing_key = "%s.%s" % (self.topic, priority.lower())
queue = kombu.entity.Queue(
channel=self.channel,
exchange=self.exchange,
durable=CONF.rabbit_durable_queues,
name=routing_key,
routing_key=routing_key)
queue.declare()
LOG.info(_("Connected to AMQP server on "
"%(hostname)s:%(port)d") % log_info)
def reconnect(self):
"""Handles reconnecting and re-establishing queues."""
while True:
self.retry_attempts += 1
try:
self._connect()
return
except self.connection_errors, e:
pass
except Exception, e:
# NOTE(comstud): Unfortunately it's possible for amqplib
# to return an error not covered by its transport
# connection_errors in the case of a timeout waiting for
# a protocol response. (See paste link in LP888621 for
# nova.) So, we check all exceptions for 'timeout' in them
# and try to reconnect in this case.
if 'timeout' not in str(e):
raise
log_info = {}
log_info['err_str'] = str(e)
log_info['max_retries'] = self.max_retries
log_info['hostname'] = CONF.rabbit_host
log_info['port'] = CONF.rabbit_port
if self.max_retries and self.retry_attempts >= self.max_retries:
LOG.exception(_('Unable to connect to AMQP server on '
'%(hostname)s:%(port)d after %(max_retries)d '
'tries: %(err_str)s') % log_info)
if self.connection:
self._close()
raise KombuMaxRetriesReached
sleep_time = self.retry_backoff * self.retry_attempts
if self.retry_max_backoff:
sleep_time = min(sleep_time, self.retry_max_backoff)
log_info['sleep_time'] = sleep_time
LOG.exception(_('AMQP server on %(hostname)s:%(port)d is'
' unreachable: %(err_str)s. Trying again in '
'%(sleep_time)d seconds.') % log_info)
time.sleep(sleep_time)
def log_failure(self, msg, priority):
"""Fallback to logging when we can't send to rabbit."""
message = _('Notification with priority %(priority)s failed: '
'msg=%(msg)s')
LOG.error(message % {'msg': msg, 'priority': priority})
def _send_message(self, msg, routing_key):
"""Send a message. Caller needs to catch exceptions for retry."""
msg = self.exchange.Message(json.dumps(msg),
content_type='application/json')
self.exchange.publish(msg, routing_key=routing_key)
def _notify(self, msg, priority):
"""Send a notification and retry if needed."""
self.retry_attempts = 0
if not self.connection:
try:
self.reconnect()
except KombuMaxRetriesReached:
self.log_failure(msg, priority)
return
routing_key = "%s.%s" % (self.topic, priority.lower())
while True:
try:
self._send_message(msg, routing_key)
return
except self.connection_errors, e:
pass
except Exception, e:
# NOTE(comstud): Unfortunately it's possible for amqplib
# to return an error not covered by its transport
# connection_errors in the case of a timeout waiting for
# a protocol response. (See paste link in LP888621 for
# nova.) So, we check all exceptions for 'timeout' in them
# and try to reconnect in this case.
if 'timeout' not in str(e):
raise
LOG.exception(_("Unable to send notification: %s") % str(e))
try:
self.reconnect()
except KombuMaxRetriesReached:
break
self.log_failure(msg, priority)
def warn(self, msg):
self._notify(msg, "WARN")
def info(self, msg):
self._notify(msg, "INFO")
def error(self, msg):
self._notify(msg, "ERROR")