bc46e64711
Avoid blocking the RPC Server thread when it attempts to acknowledge the RPC request message. Blocking is unnecessary as the acknowledge command does not return a status and can be processed asynchronously from the server thread. Avoiding this context switch improves overall RPC call throughput according to the simulator tool by approximately ten percent on my test systems. Change-Id: I71548eb6f9f7dcaf74cb426d4e9b369b54856419
400 lines
16 KiB
Python
400 lines
16 KiB
Python
# Copyright 2014, 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.
|
|
|
|
"""
|
|
Driver for the 'amqp' transport.
|
|
|
|
This module provides a transport driver that speaks version 1.0 of the AMQP
|
|
messaging protocol. The driver sends messages and creates subscriptions via
|
|
'tasks' that are performed on its behalf via the controller module.
|
|
"""
|
|
|
|
import collections
|
|
import logging
|
|
import os
|
|
import threading
|
|
import uuid
|
|
|
|
from oslo_config import cfg
|
|
from oslo_messaging.target import Target
|
|
from oslo_serialization import jsonutils
|
|
from oslo_utils import importutils
|
|
from oslo_utils import timeutils
|
|
|
|
from oslo_messaging._drivers.amqp1_driver.eventloop import compute_timeout
|
|
from oslo_messaging._drivers.amqp1_driver import opts
|
|
from oslo_messaging._drivers import base
|
|
from oslo_messaging._drivers import common
|
|
from oslo_messaging._i18n import _LI, _LW
|
|
|
|
|
|
proton = importutils.try_import('proton')
|
|
controller = importutils.try_import(
|
|
'oslo_messaging._drivers.amqp1_driver.controller'
|
|
)
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
def marshal_response(reply, failure):
|
|
# TODO(grs): do replies have a context?
|
|
# NOTE(flaper87): Set inferred to True since rabbitmq-amqp-1.0 doesn't
|
|
# have support for vbin8.
|
|
msg = proton.Message(inferred=True)
|
|
if failure:
|
|
failure = common.serialize_remote_exception(failure)
|
|
data = {"failure": failure}
|
|
else:
|
|
data = {"response": reply}
|
|
msg.body = jsonutils.dumps(data)
|
|
return msg
|
|
|
|
|
|
def unmarshal_response(message, allowed):
|
|
# TODO(kgiusti) This may fail to unpack and raise an exception. Need to
|
|
# communicate this to the caller!
|
|
data = jsonutils.loads(message.body)
|
|
failure = data.get('failure')
|
|
if failure is not None:
|
|
raise common.deserialize_remote_exception(failure, allowed)
|
|
return data.get("response")
|
|
|
|
|
|
def marshal_request(request, context, envelope):
|
|
# NOTE(flaper87): Set inferred to True since rabbitmq-amqp-1.0 doesn't
|
|
# have support for vbin8.
|
|
msg = proton.Message(inferred=True)
|
|
if envelope:
|
|
request = common.serialize_msg(request)
|
|
data = {
|
|
"request": request,
|
|
"context": context
|
|
}
|
|
msg.body = jsonutils.dumps(data)
|
|
return msg
|
|
|
|
|
|
def unmarshal_request(message):
|
|
data = jsonutils.loads(message.body)
|
|
msg = common.deserialize_msg(data.get("request"))
|
|
return (msg, data.get("context"))
|
|
|
|
|
|
class ProtonIncomingMessage(base.RpcIncomingMessage):
|
|
def __init__(self, listener, ctxt, request, message, disposition):
|
|
super(ProtonIncomingMessage, self).__init__(ctxt, request)
|
|
self.listener = listener
|
|
self._reply_to = message.reply_to
|
|
self._correlation_id = message.id
|
|
self._disposition = disposition
|
|
|
|
def reply(self, reply=None, failure=None):
|
|
"""Schedule an RPCReplyTask to send the reply."""
|
|
if self._reply_to:
|
|
response = marshal_response(reply, failure)
|
|
response.correlation_id = self._correlation_id
|
|
driver = self.listener.driver
|
|
deadline = compute_timeout(driver._default_reply_timeout)
|
|
ack = not driver._pre_settle_reply
|
|
task = controller.SendTask("RPC Reply", response, self._reply_to,
|
|
# analogous to kombu missing dest t/o:
|
|
deadline,
|
|
retry=0,
|
|
wait_for_ack=ack)
|
|
driver._ctrl.add_task(task)
|
|
rc = task.wait()
|
|
if rc:
|
|
# something failed. Not much we can do at this point but log
|
|
LOG.debug("RPC Reply failed to send: %s", str(rc))
|
|
else:
|
|
LOG.debug("Ignoring reply as no reply address available")
|
|
|
|
def acknowledge(self):
|
|
"""Schedule a MessageDispositionTask to send the settlement."""
|
|
task = controller.MessageDispositionTask(self._disposition,
|
|
released=False)
|
|
self.listener.driver._ctrl.add_task(task)
|
|
|
|
def requeue(self):
|
|
"""Schedule a MessageDispositionTask to release the message"""
|
|
task = controller.MessageDispositionTask(self._disposition,
|
|
released=True)
|
|
self.listener.driver._ctrl.add_task(task)
|
|
|
|
|
|
class Queue(object):
|
|
def __init__(self):
|
|
self._queue = collections.deque()
|
|
self._lock = threading.Lock()
|
|
self._pop_wake_condition = threading.Condition(self._lock)
|
|
self._started = True
|
|
|
|
def put(self, item):
|
|
with self._lock:
|
|
self._queue.appendleft(item)
|
|
self._pop_wake_condition.notify()
|
|
|
|
def pop(self, timeout):
|
|
with timeutils.StopWatch(timeout) as stop_watcher:
|
|
with self._lock:
|
|
while len(self._queue) == 0:
|
|
if stop_watcher.expired() or not self._started:
|
|
return None
|
|
self._pop_wake_condition.wait(
|
|
stop_watcher.leftover(return_none=True)
|
|
)
|
|
return self._queue.pop()
|
|
|
|
def stop(self):
|
|
with self._lock:
|
|
self._started = False
|
|
self._pop_wake_condition.notify_all()
|
|
|
|
|
|
class ProtonListener(base.PollStyleListener):
|
|
def __init__(self, driver):
|
|
super(ProtonListener, self).__init__(driver.prefetch_size)
|
|
self.driver = driver
|
|
self.incoming = Queue()
|
|
self.id = uuid.uuid4().hex
|
|
|
|
def stop(self):
|
|
self.incoming.stop()
|
|
|
|
@base.batch_poll_helper
|
|
def poll(self, timeout=None):
|
|
qentry = self.incoming.pop(timeout)
|
|
if qentry is None:
|
|
return None
|
|
message = qentry['message']
|
|
request, ctxt = unmarshal_request(message)
|
|
disposition = qentry['disposition']
|
|
return ProtonIncomingMessage(self, ctxt, request, message, disposition)
|
|
|
|
|
|
class ProtonDriver(base.BaseDriver):
|
|
"""AMQP 1.0 Driver
|
|
|
|
See :doc:`AMQP1.0` for details.
|
|
"""
|
|
|
|
def __init__(self, conf, url,
|
|
default_exchange=None, allowed_remote_exmods=[]):
|
|
if proton is None or controller is None:
|
|
raise NotImplementedError("Proton AMQP C libraries not installed")
|
|
|
|
super(ProtonDriver, self).__init__(conf, url, default_exchange,
|
|
allowed_remote_exmods)
|
|
|
|
opt_group = cfg.OptGroup(name='oslo_messaging_amqp',
|
|
title='AMQP 1.0 driver options')
|
|
conf.register_group(opt_group)
|
|
conf.register_opts(opts.amqp1_opts, group=opt_group)
|
|
|
|
self._hosts = url.hosts
|
|
self._conf = conf
|
|
self._default_exchange = default_exchange
|
|
|
|
# lazy connection setup - don't create the controller until
|
|
# after the first messaging request:
|
|
self._ctrl = None
|
|
self._pid = None
|
|
self._lock = threading.Lock()
|
|
|
|
# timeout for message acknowledgement
|
|
opt_name = conf.oslo_messaging_amqp
|
|
self._default_reply_timeout = opt_name.default_reply_timeout
|
|
self._default_send_timeout = opt_name.default_send_timeout
|
|
self._default_notify_timeout = opt_name.default_notify_timeout
|
|
|
|
# which message types should be sent pre-settled?
|
|
ps = [s.lower() for s in opt_name.pre_settled]
|
|
self._pre_settle_call = 'rpc-call' in ps
|
|
self._pre_settle_reply = 'rpc-reply' in ps
|
|
self._pre_settle_cast = 'rpc-cast' in ps
|
|
self._pre_settle_notify = 'notify' in ps
|
|
bad_opts = set(ps).difference(['rpc-call', 'rpc-reply',
|
|
'rpc-cast', 'notify'])
|
|
if bad_opts:
|
|
LOG.warning(_LW("Ignoring unrecognized pre_settle value(s): %s"),
|
|
" ".join(bad_opts))
|
|
|
|
def _ensure_connect_called(func):
|
|
"""Causes a new controller to be created when the messaging service is
|
|
first used by the current process. It is safe to push tasks to it
|
|
whether connected or not, but those tasks won't be processed until
|
|
connection completes.
|
|
"""
|
|
def wrap(self, *args, **kws):
|
|
with self._lock:
|
|
# check to see if a fork was done after the Controller and its
|
|
# I/O thread was spawned. old_pid will be None the first time
|
|
# this is called which will cause the Controller to be created.
|
|
old_pid = self._pid
|
|
self._pid = os.getpid()
|
|
|
|
if old_pid != self._pid:
|
|
if self._ctrl is not None:
|
|
# fork was called after the Controller was created, and
|
|
# we are now executing as the child process. Do not
|
|
# touch the existing Controller - it is owned by the
|
|
# parent. Best we can do here is simply drop it and
|
|
# hope we get lucky.
|
|
LOG.warning(_LW("Process forked after connection "
|
|
"established!"))
|
|
self._ctrl = None
|
|
# Create a Controller that connects to the messaging
|
|
# service:
|
|
self._ctrl = controller.Controller(self._hosts,
|
|
self._default_exchange,
|
|
self._conf)
|
|
self._ctrl.connect()
|
|
return func(self, *args, **kws)
|
|
return wrap
|
|
|
|
@_ensure_connect_called
|
|
def send(self, target, ctxt, message,
|
|
wait_for_reply=False, timeout=None, envelope=False,
|
|
retry=None):
|
|
"""Send a message to the given target.
|
|
|
|
:param target: destination for message
|
|
:type target: oslo_messaging.Target
|
|
:param ctxt: message context
|
|
:type ctxt: dict
|
|
:param message: message payload
|
|
:type message: dict
|
|
:param wait_for_reply: expects a reply message, wait for it
|
|
:type wait_for_reply: bool
|
|
:param timeout: raise exception if send does not complete within
|
|
timeout seconds. None == no timeout.
|
|
:type timeout: float
|
|
:param envelope: Encapsulate message in an envelope
|
|
:type envelope: bool
|
|
:param retry: (optional) maximum re-send attempts on recoverable error
|
|
None or -1 means to retry forever
|
|
0 means no retry
|
|
N means N retries
|
|
:type retry: int
|
|
"""
|
|
request = marshal_request(message, ctxt, envelope)
|
|
expire = 0
|
|
if timeout:
|
|
expire = compute_timeout(timeout) # when the caller times out
|
|
# amqp uses millisecond time values, timeout is seconds
|
|
request.ttl = int(timeout * 1000)
|
|
request.expiry_time = int(expire * 1000)
|
|
else:
|
|
# no timeout provided by application. If the backend is queueless
|
|
# this could lead to a hang - provide a default to prevent this
|
|
# TODO(kgiusti) only do this if brokerless backend
|
|
expire = compute_timeout(self._default_send_timeout)
|
|
if wait_for_reply:
|
|
ack = not self._pre_settle_call
|
|
task = controller.RPCCallTask(target, request, expire, retry,
|
|
wait_for_ack=ack)
|
|
else:
|
|
ack = not self._pre_settle_cast
|
|
task = controller.SendTask("RPC Cast", request, target, expire,
|
|
retry, wait_for_ack=ack)
|
|
self._ctrl.add_task(task)
|
|
|
|
reply = task.wait()
|
|
if isinstance(reply, Exception):
|
|
raise reply
|
|
if reply:
|
|
# TODO(kgiusti) how to handle failure to un-marshal?
|
|
# Must log, and determine best way to communicate this failure
|
|
# back up to the caller
|
|
reply = unmarshal_response(reply, self._allowed_remote_exmods)
|
|
return reply
|
|
|
|
@_ensure_connect_called
|
|
def send_notification(self, target, ctxt, message, version,
|
|
retry=None):
|
|
"""Send a notification message to the given target.
|
|
|
|
:param target: destination for message
|
|
:type target: oslo_messaging.Target
|
|
:param ctxt: message context
|
|
:type ctxt: dict
|
|
:param message: message payload
|
|
:type message: dict
|
|
:param version: message envelope version
|
|
:type version: float
|
|
:param retry: (optional) maximum re-send attempts on recoverable error
|
|
None or -1 means to retry forever
|
|
0 means no retry
|
|
N means N retries
|
|
:type retry: int
|
|
"""
|
|
request = marshal_request(message, ctxt, (version == 2.0))
|
|
# no timeout is applied to notifications, however if the backend is
|
|
# queueless this could lead to a hang - provide a default to prevent
|
|
# this
|
|
# TODO(kgiusti) should raise NotImplemented if not broker backend
|
|
deadline = compute_timeout(self._default_notify_timeout)
|
|
ack = not self._pre_settle_notify
|
|
task = controller.SendTask("Notify", request, target,
|
|
deadline, retry, wait_for_ack=ack,
|
|
notification=True)
|
|
self._ctrl.add_task(task)
|
|
rc = task.wait()
|
|
if isinstance(rc, Exception):
|
|
raise rc
|
|
|
|
@_ensure_connect_called
|
|
def listen(self, target, batch_size, batch_timeout):
|
|
"""Construct a Listener for the given target."""
|
|
LOG.debug("Listen to %s", target)
|
|
listener = ProtonListener(self)
|
|
task = controller.SubscribeTask(target, listener)
|
|
self._ctrl.add_task(task)
|
|
task.wait()
|
|
return base.PollStyleListenerAdapter(listener, batch_size,
|
|
batch_timeout)
|
|
|
|
@_ensure_connect_called
|
|
def listen_for_notifications(self, targets_and_priorities, pool,
|
|
batch_size, batch_timeout):
|
|
"""Construct a Listener for notifications on the given target and
|
|
priority.
|
|
"""
|
|
# TODO(kgiusti) should raise NotImplemented if not broker backend
|
|
LOG.debug("Listen for notifications %s", targets_and_priorities)
|
|
if pool:
|
|
raise NotImplementedError('"pool" not implemented by '
|
|
'this transport driver')
|
|
listener = ProtonListener(self)
|
|
# this is how the destination target is created by the notifier,
|
|
# see MessagingDriver.notify in oslo_messaging/notify/messaging.py
|
|
for target, priority in targets_and_priorities:
|
|
topic = '%s.%s' % (target.topic, priority)
|
|
# Sooo... the exchange is simply discarded? (see above comment)
|
|
task = controller.SubscribeTask(Target(topic=topic),
|
|
listener, notifications=True)
|
|
self._ctrl.add_task(task)
|
|
task.wait()
|
|
return base.PollStyleListenerAdapter(listener, batch_size,
|
|
batch_timeout)
|
|
|
|
def cleanup(self):
|
|
"""Release all resources."""
|
|
if self._ctrl:
|
|
self._ctrl.shutdown()
|
|
self._ctrl = None
|
|
LOG.info(_LI("AMQP 1.0 messaging driver shutdown"))
|
|
|
|
def require_features(self, requeue=True):
|
|
pass
|