58d42b6558
blueprint scalable-agent-comms This is the first stage of the blueprint. This adds support to the linux bridge plugin. The development followed the design described in: https://docs.google.com/document/d/1MbcBA2Os4b98ybdgAw2qe_68R1NG6KMh8zdZKgOlpvg/edit?pli=1 Change-Id: I4004c05a63ce49f020c2016c8763e73238b465a7
600 lines
20 KiB
Python
600 lines
20 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
# Copyright 2011 OpenStack LLC
|
|
# Copyright 2011 - 2012, Red Hat, 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 functools
|
|
import itertools
|
|
import logging
|
|
import time
|
|
import uuid
|
|
|
|
import eventlet
|
|
import greenlet
|
|
import qpid.messaging
|
|
import qpid.messaging.exceptions
|
|
|
|
from quantum.openstack.common import cfg
|
|
from quantum.openstack.common.gettextutils import _
|
|
from quantum.openstack.common import jsonutils
|
|
from quantum.openstack.common.rpc import amqp as rpc_amqp
|
|
from quantum.openstack.common.rpc import common as rpc_common
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
qpid_opts = [
|
|
cfg.StrOpt('qpid_hostname',
|
|
default='localhost',
|
|
help='Qpid broker hostname'),
|
|
cfg.StrOpt('qpid_port',
|
|
default='5672',
|
|
help='Qpid broker port'),
|
|
cfg.StrOpt('qpid_username',
|
|
default='',
|
|
help='Username for qpid connection'),
|
|
cfg.StrOpt('qpid_password',
|
|
default='',
|
|
help='Password for qpid connection'),
|
|
cfg.StrOpt('qpid_sasl_mechanisms',
|
|
default='',
|
|
help='Space separated list of SASL mechanisms to use for auth'),
|
|
cfg.BoolOpt('qpid_reconnect',
|
|
default=True,
|
|
help='Automatically reconnect'),
|
|
cfg.IntOpt('qpid_reconnect_timeout',
|
|
default=0,
|
|
help='Reconnection timeout in seconds'),
|
|
cfg.IntOpt('qpid_reconnect_limit',
|
|
default=0,
|
|
help='Max reconnections before giving up'),
|
|
cfg.IntOpt('qpid_reconnect_interval_min',
|
|
default=0,
|
|
help='Minimum seconds between reconnection attempts'),
|
|
cfg.IntOpt('qpid_reconnect_interval_max',
|
|
default=0,
|
|
help='Maximum seconds between reconnection attempts'),
|
|
cfg.IntOpt('qpid_reconnect_interval',
|
|
default=0,
|
|
help='Equivalent to setting max and min to the same value'),
|
|
cfg.IntOpt('qpid_heartbeat',
|
|
default=5,
|
|
help='Seconds between connection keepalive heartbeats'),
|
|
cfg.StrOpt('qpid_protocol',
|
|
default='tcp',
|
|
help="Transport to use, either 'tcp' or 'ssl'"),
|
|
cfg.BoolOpt('qpid_tcp_nodelay',
|
|
default=True,
|
|
help='Disable Nagle algorithm'),
|
|
]
|
|
|
|
cfg.CONF.register_opts(qpid_opts)
|
|
|
|
|
|
class ConsumerBase(object):
|
|
"""Consumer base class."""
|
|
|
|
def __init__(self, session, callback, node_name, node_opts,
|
|
link_name, link_opts):
|
|
"""Declare a queue on an amqp session.
|
|
|
|
'session' is the amqp session to use
|
|
'callback' is the callback to call when messages are received
|
|
'node_name' is the first part of the Qpid address string, before ';'
|
|
'node_opts' will be applied to the "x-declare" section of "node"
|
|
in the address string.
|
|
'link_name' goes into the "name" field of the "link" in the address
|
|
string
|
|
'link_opts' will be applied to the "x-declare" section of "link"
|
|
in the address string.
|
|
"""
|
|
self.callback = callback
|
|
self.receiver = None
|
|
self.session = None
|
|
|
|
addr_opts = {
|
|
"create": "always",
|
|
"node": {
|
|
"type": "topic",
|
|
"x-declare": {
|
|
"durable": True,
|
|
"auto-delete": True,
|
|
},
|
|
},
|
|
"link": {
|
|
"name": link_name,
|
|
"durable": True,
|
|
"x-declare": {
|
|
"durable": False,
|
|
"auto-delete": True,
|
|
"exclusive": False,
|
|
},
|
|
},
|
|
}
|
|
addr_opts["node"]["x-declare"].update(node_opts)
|
|
addr_opts["link"]["x-declare"].update(link_opts)
|
|
|
|
self.address = "%s ; %s" % (node_name, jsonutils.dumps(addr_opts))
|
|
|
|
self.reconnect(session)
|
|
|
|
def reconnect(self, session):
|
|
"""Re-declare the receiver after a qpid reconnect"""
|
|
self.session = session
|
|
self.receiver = session.receiver(self.address)
|
|
self.receiver.capacity = 1
|
|
|
|
def consume(self):
|
|
"""Fetch the message and pass it to the callback object"""
|
|
message = self.receiver.fetch()
|
|
try:
|
|
self.callback(message.content)
|
|
except Exception:
|
|
LOG.exception(_("Failed to process message... skipping it."))
|
|
finally:
|
|
self.session.acknowledge(message)
|
|
|
|
def get_receiver(self):
|
|
return self.receiver
|
|
|
|
|
|
class DirectConsumer(ConsumerBase):
|
|
"""Queue/consumer class for 'direct'"""
|
|
|
|
def __init__(self, conf, session, msg_id, callback):
|
|
"""Init a 'direct' queue.
|
|
|
|
'session' is the amqp session to use
|
|
'msg_id' is the msg_id to listen on
|
|
'callback' is the callback to call when messages are received
|
|
"""
|
|
|
|
super(DirectConsumer, self).__init__(session, callback,
|
|
"%s/%s" % (msg_id, msg_id),
|
|
{"type": "direct"},
|
|
msg_id,
|
|
{"exclusive": True})
|
|
|
|
|
|
class TopicConsumer(ConsumerBase):
|
|
"""Consumer class for 'topic'"""
|
|
|
|
def __init__(self, conf, session, topic, callback, name=None):
|
|
"""Init a 'topic' queue.
|
|
|
|
:param session: the amqp session to use
|
|
:param topic: is the topic to listen on
|
|
:paramtype topic: str
|
|
:param callback: the callback to call when messages are received
|
|
:param name: optional queue name, defaults to topic
|
|
"""
|
|
|
|
super(TopicConsumer, self).__init__(session, callback,
|
|
"%s/%s" % (conf.control_exchange,
|
|
topic),
|
|
{}, name or topic, {})
|
|
|
|
|
|
class FanoutConsumer(ConsumerBase):
|
|
"""Consumer class for 'fanout'"""
|
|
|
|
def __init__(self, conf, session, topic, callback):
|
|
"""Init a 'fanout' queue.
|
|
|
|
'session' is the amqp session to use
|
|
'topic' is the topic to listen on
|
|
'callback' is the callback to call when messages are received
|
|
"""
|
|
|
|
super(FanoutConsumer, self).__init__(
|
|
session, callback,
|
|
"%s_fanout" % topic,
|
|
{"durable": False, "type": "fanout"},
|
|
"%s_fanout_%s" % (topic, uuid.uuid4().hex),
|
|
{"exclusive": True})
|
|
|
|
|
|
class Publisher(object):
|
|
"""Base Publisher class"""
|
|
|
|
def __init__(self, session, node_name, node_opts=None):
|
|
"""Init the Publisher class with the exchange_name, routing_key,
|
|
and other options
|
|
"""
|
|
self.sender = None
|
|
self.session = session
|
|
|
|
addr_opts = {
|
|
"create": "always",
|
|
"node": {
|
|
"type": "topic",
|
|
"x-declare": {
|
|
"durable": False,
|
|
# auto-delete isn't implemented for exchanges in qpid,
|
|
# but put in here anyway
|
|
"auto-delete": True,
|
|
},
|
|
},
|
|
}
|
|
if node_opts:
|
|
addr_opts["node"]["x-declare"].update(node_opts)
|
|
|
|
self.address = "%s ; %s" % (node_name, jsonutils.dumps(addr_opts))
|
|
|
|
self.reconnect(session)
|
|
|
|
def reconnect(self, session):
|
|
"""Re-establish the Sender after a reconnection"""
|
|
self.sender = session.sender(self.address)
|
|
|
|
def send(self, msg):
|
|
"""Send a message"""
|
|
self.sender.send(msg)
|
|
|
|
|
|
class DirectPublisher(Publisher):
|
|
"""Publisher class for 'direct'"""
|
|
def __init__(self, conf, session, msg_id):
|
|
"""Init a 'direct' publisher."""
|
|
super(DirectPublisher, self).__init__(session, msg_id,
|
|
{"type": "Direct"})
|
|
|
|
|
|
class TopicPublisher(Publisher):
|
|
"""Publisher class for 'topic'"""
|
|
def __init__(self, conf, session, topic):
|
|
"""init a 'topic' publisher.
|
|
"""
|
|
super(TopicPublisher, self).__init__(
|
|
session,
|
|
"%s/%s" % (conf.control_exchange, topic))
|
|
|
|
|
|
class FanoutPublisher(Publisher):
|
|
"""Publisher class for 'fanout'"""
|
|
def __init__(self, conf, session, topic):
|
|
"""init a 'fanout' publisher.
|
|
"""
|
|
super(FanoutPublisher, self).__init__(
|
|
session,
|
|
"%s_fanout" % topic, {"type": "fanout"})
|
|
|
|
|
|
class NotifyPublisher(Publisher):
|
|
"""Publisher class for notifications"""
|
|
def __init__(self, conf, session, topic):
|
|
"""init a 'topic' publisher.
|
|
"""
|
|
super(NotifyPublisher, self).__init__(
|
|
session,
|
|
"%s/%s" % (conf.control_exchange, topic),
|
|
{"durable": True})
|
|
|
|
|
|
class Connection(object):
|
|
"""Connection object."""
|
|
|
|
pool = None
|
|
|
|
def __init__(self, conf, server_params=None):
|
|
self.session = None
|
|
self.consumers = {}
|
|
self.consumer_thread = None
|
|
self.conf = conf
|
|
|
|
if server_params is None:
|
|
server_params = {}
|
|
|
|
default_params = dict(hostname=self.conf.qpid_hostname,
|
|
port=self.conf.qpid_port,
|
|
username=self.conf.qpid_username,
|
|
password=self.conf.qpid_password)
|
|
|
|
params = server_params
|
|
for key in default_params.keys():
|
|
params.setdefault(key, default_params[key])
|
|
|
|
self.broker = params['hostname'] + ":" + str(params['port'])
|
|
# Create the connection - this does not open the connection
|
|
self.connection = qpid.messaging.Connection(self.broker)
|
|
|
|
# Check if flags are set and if so set them for the connection
|
|
# before we call open
|
|
self.connection.username = params['username']
|
|
self.connection.password = params['password']
|
|
self.connection.sasl_mechanisms = self.conf.qpid_sasl_mechanisms
|
|
self.connection.reconnect = self.conf.qpid_reconnect
|
|
if self.conf.qpid_reconnect_timeout:
|
|
self.connection.reconnect_timeout = (
|
|
self.conf.qpid_reconnect_timeout)
|
|
if self.conf.qpid_reconnect_limit:
|
|
self.connection.reconnect_limit = self.conf.qpid_reconnect_limit
|
|
if self.conf.qpid_reconnect_interval_max:
|
|
self.connection.reconnect_interval_max = (
|
|
self.conf.qpid_reconnect_interval_max)
|
|
if self.conf.qpid_reconnect_interval_min:
|
|
self.connection.reconnect_interval_min = (
|
|
self.conf.qpid_reconnect_interval_min)
|
|
if self.conf.qpid_reconnect_interval:
|
|
self.connection.reconnect_interval = (
|
|
self.conf.qpid_reconnect_interval)
|
|
self.connection.heartbeat = self.conf.qpid_heartbeat
|
|
self.connection.protocol = self.conf.qpid_protocol
|
|
self.connection.tcp_nodelay = self.conf.qpid_tcp_nodelay
|
|
|
|
# Open is part of reconnect -
|
|
# NOTE(WGH) not sure we need this with the reconnect flags
|
|
self.reconnect()
|
|
|
|
def _register_consumer(self, consumer):
|
|
self.consumers[str(consumer.get_receiver())] = consumer
|
|
|
|
def _lookup_consumer(self, receiver):
|
|
return self.consumers[str(receiver)]
|
|
|
|
def reconnect(self):
|
|
"""Handles reconnecting and re-establishing sessions and queues"""
|
|
if self.connection.opened():
|
|
try:
|
|
self.connection.close()
|
|
except qpid.messaging.exceptions.ConnectionError:
|
|
pass
|
|
|
|
while True:
|
|
try:
|
|
self.connection.open()
|
|
except qpid.messaging.exceptions.ConnectionError, e:
|
|
LOG.error(_('Unable to connect to AMQP server: %s'), e)
|
|
time.sleep(self.conf.qpid_reconnect_interval or 1)
|
|
else:
|
|
break
|
|
|
|
LOG.info(_('Connected to AMQP server on %s'), self.broker)
|
|
|
|
self.session = self.connection.session()
|
|
|
|
for consumer in self.consumers.itervalues():
|
|
consumer.reconnect(self.session)
|
|
|
|
if self.consumers:
|
|
LOG.debug(_("Re-established AMQP queues"))
|
|
|
|
def ensure(self, error_callback, method, *args, **kwargs):
|
|
while True:
|
|
try:
|
|
return method(*args, **kwargs)
|
|
except (qpid.messaging.exceptions.Empty,
|
|
qpid.messaging.exceptions.ConnectionError), e:
|
|
if error_callback:
|
|
error_callback(e)
|
|
self.reconnect()
|
|
|
|
def close(self):
|
|
"""Close/release this connection"""
|
|
self.cancel_consumer_thread()
|
|
self.connection.close()
|
|
self.connection = None
|
|
|
|
def reset(self):
|
|
"""Reset a connection so it can be used again"""
|
|
self.cancel_consumer_thread()
|
|
self.session.close()
|
|
self.session = self.connection.session()
|
|
self.consumers = {}
|
|
|
|
def declare_consumer(self, consumer_cls, topic, callback):
|
|
"""Create a Consumer using the class that was passed in and
|
|
add it to our list of consumers
|
|
"""
|
|
def _connect_error(exc):
|
|
log_info = {'topic': topic, 'err_str': str(exc)}
|
|
LOG.error(_("Failed to declare consumer for topic '%(topic)s': "
|
|
"%(err_str)s") % log_info)
|
|
|
|
def _declare_consumer():
|
|
consumer = consumer_cls(self.conf, self.session, topic, callback)
|
|
self._register_consumer(consumer)
|
|
return consumer
|
|
|
|
return self.ensure(_connect_error, _declare_consumer)
|
|
|
|
def iterconsume(self, limit=None, timeout=None):
|
|
"""Return an iterator that will consume from all queues/consumers"""
|
|
|
|
def _error_callback(exc):
|
|
if isinstance(exc, qpid.messaging.exceptions.Empty):
|
|
LOG.exception(_('Timed out waiting for RPC response: %s') %
|
|
str(exc))
|
|
raise rpc_common.Timeout()
|
|
else:
|
|
LOG.exception(_('Failed to consume message from queue: %s') %
|
|
str(exc))
|
|
|
|
def _consume():
|
|
nxt_receiver = self.session.next_receiver(timeout=timeout)
|
|
try:
|
|
self._lookup_consumer(nxt_receiver).consume()
|
|
except Exception:
|
|
LOG.exception(_("Error processing message. Skipping it."))
|
|
|
|
for iteration in itertools.count(0):
|
|
if limit and iteration >= limit:
|
|
raise StopIteration
|
|
yield self.ensure(_error_callback, _consume)
|
|
|
|
def cancel_consumer_thread(self):
|
|
"""Cancel a consumer thread"""
|
|
if self.consumer_thread is not None:
|
|
self.consumer_thread.kill()
|
|
try:
|
|
self.consumer_thread.wait()
|
|
except greenlet.GreenletExit:
|
|
pass
|
|
self.consumer_thread = None
|
|
|
|
def publisher_send(self, cls, topic, msg):
|
|
"""Send to a publisher based on the publisher class"""
|
|
|
|
def _connect_error(exc):
|
|
log_info = {'topic': topic, 'err_str': str(exc)}
|
|
LOG.exception(_("Failed to publish message to topic "
|
|
"'%(topic)s': %(err_str)s") % log_info)
|
|
|
|
def _publisher_send():
|
|
publisher = cls(self.conf, self.session, topic)
|
|
publisher.send(msg)
|
|
|
|
return self.ensure(_connect_error, _publisher_send)
|
|
|
|
def declare_direct_consumer(self, topic, callback):
|
|
"""Create a 'direct' queue.
|
|
In nova's use, this is generally a msg_id queue used for
|
|
responses for call/multicall
|
|
"""
|
|
self.declare_consumer(DirectConsumer, topic, callback)
|
|
|
|
def declare_topic_consumer(self, topic, callback=None, queue_name=None):
|
|
"""Create a 'topic' consumer."""
|
|
self.declare_consumer(functools.partial(TopicConsumer,
|
|
name=queue_name,
|
|
),
|
|
topic, callback)
|
|
|
|
def declare_fanout_consumer(self, topic, callback):
|
|
"""Create a 'fanout' consumer"""
|
|
self.declare_consumer(FanoutConsumer, topic, callback)
|
|
|
|
def direct_send(self, msg_id, msg):
|
|
"""Send a 'direct' message"""
|
|
self.publisher_send(DirectPublisher, msg_id, msg)
|
|
|
|
def topic_send(self, topic, msg):
|
|
"""Send a 'topic' message"""
|
|
self.publisher_send(TopicPublisher, topic, msg)
|
|
|
|
def fanout_send(self, topic, msg):
|
|
"""Send a 'fanout' message"""
|
|
self.publisher_send(FanoutPublisher, topic, msg)
|
|
|
|
def notify_send(self, topic, msg, **kwargs):
|
|
"""Send a notify message on a topic"""
|
|
self.publisher_send(NotifyPublisher, topic, msg)
|
|
|
|
def consume(self, limit=None):
|
|
"""Consume from all queues/consumers"""
|
|
it = self.iterconsume(limit=limit)
|
|
while True:
|
|
try:
|
|
it.next()
|
|
except StopIteration:
|
|
return
|
|
|
|
def consume_in_thread(self):
|
|
"""Consumer from all queues/consumers in a greenthread"""
|
|
def _consumer_thread():
|
|
try:
|
|
self.consume()
|
|
except greenlet.GreenletExit:
|
|
return
|
|
if self.consumer_thread is None:
|
|
self.consumer_thread = eventlet.spawn(_consumer_thread)
|
|
return self.consumer_thread
|
|
|
|
def create_consumer(self, topic, proxy, fanout=False):
|
|
"""Create a consumer that calls a method in a proxy object"""
|
|
proxy_cb = rpc_amqp.ProxyCallback(
|
|
self.conf, proxy,
|
|
rpc_amqp.get_connection_pool(self.conf, Connection))
|
|
|
|
if fanout:
|
|
consumer = FanoutConsumer(self.conf, self.session, topic, proxy_cb)
|
|
else:
|
|
consumer = TopicConsumer(self.conf, self.session, topic, proxy_cb)
|
|
|
|
self._register_consumer(consumer)
|
|
|
|
return consumer
|
|
|
|
def create_worker(self, topic, proxy, pool_name):
|
|
"""Create a worker that calls a method in a proxy object"""
|
|
proxy_cb = rpc_amqp.ProxyCallback(
|
|
self.conf, proxy,
|
|
rpc_amqp.get_connection_pool(self.conf, Connection))
|
|
|
|
consumer = TopicConsumer(self.conf, self.session, topic, proxy_cb,
|
|
name=pool_name)
|
|
|
|
self._register_consumer(consumer)
|
|
|
|
return consumer
|
|
|
|
|
|
def create_connection(conf, new=True):
|
|
"""Create a connection"""
|
|
return rpc_amqp.create_connection(
|
|
conf, new,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def multicall(conf, context, topic, msg, timeout=None):
|
|
"""Make a call that returns multiple times."""
|
|
return rpc_amqp.multicall(
|
|
conf, context, topic, msg, timeout,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def call(conf, context, topic, msg, timeout=None):
|
|
"""Sends a message on a topic and wait for a response."""
|
|
return rpc_amqp.call(
|
|
conf, context, topic, msg, timeout,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def cast(conf, context, topic, msg):
|
|
"""Sends a message on a topic without waiting for a response."""
|
|
return rpc_amqp.cast(
|
|
conf, context, topic, msg,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def fanout_cast(conf, context, topic, msg):
|
|
"""Sends a message on a fanout exchange without waiting for a response."""
|
|
return rpc_amqp.fanout_cast(
|
|
conf, context, topic, msg,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def cast_to_server(conf, context, server_params, topic, msg):
|
|
"""Sends a message on a topic to a specific server."""
|
|
return rpc_amqp.cast_to_server(
|
|
conf, context, server_params, topic, msg,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def fanout_cast_to_server(conf, context, server_params, topic, msg):
|
|
"""Sends a message on a fanout exchange to a specific server."""
|
|
return rpc_amqp.fanout_cast_to_server(
|
|
conf, context, server_params, topic, msg,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def notify(conf, context, topic, msg):
|
|
"""Sends a notification event on a topic."""
|
|
return rpc_amqp.notify(conf, context, topic, msg,
|
|
rpc_amqp.get_connection_pool(conf, Connection))
|
|
|
|
|
|
def cleanup():
|
|
return rpc_amqp.cleanup(Connection.pool)
|