oslo.messaging/oslo_messaging/_drivers/zmq_driver/client/publishers/zmq_req_publisher.py

86 lines
3.0 KiB
Python

# Copyright 2015 Mirantis, 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 contextlib
import logging
import oslo_messaging
from oslo_messaging._drivers import common as rpc_common
from oslo_messaging._drivers.zmq_driver.client.publishers\
import zmq_publisher_base
from oslo_messaging._drivers.zmq_driver import zmq_address
from oslo_messaging._drivers.zmq_driver import zmq_async
from oslo_messaging._drivers.zmq_driver import zmq_names
from oslo_messaging._i18n import _LE, _LI
LOG = logging.getLogger(__name__)
zmq = zmq_async.import_zmq()
class ReqPublisher(zmq_publisher_base.PublisherBase):
def send_request(self, request):
if request.msg_type != zmq_names.CALL_TYPE:
raise zmq_publisher_base.UnsupportedSendPattern(request.msg_type)
socket = self._connect_to_host(request.target)
self._send_request(socket, request)
return self._receive_reply(socket, request)
def _connect_to_host(self, target):
try:
self.zmq_context = zmq.Context()
socket = self.zmq_context.socket(zmq.REQ)
host = self.matchmaker.get_single_host(target)
connect_address = zmq_address.get_tcp_direct_address(host)
LOG.info(_LI("Connecting REQ to %s") % connect_address)
socket.connect(connect_address)
self.outbound_sockets[str(target)] = socket
return socket
except zmq.ZMQError as e:
errmsg = _LE("Error connecting to socket: %s") % str(e)
LOG.error(errmsg)
raise rpc_common.RPCException(errmsg)
@staticmethod
def _receive_reply(socket, request):
def _receive_method(socket):
return socket.recv_pyobj()
# NOTE(ozamiatin): Check for retry here (no retries now)
with contextlib.closing(zmq_async.get_reply_poller()) as poller:
poller.register(socket, recv_method=_receive_method)
reply, socket = poller.poll(timeout=request.timeout)
if reply is None:
raise oslo_messaging.MessagingTimeout(
"Timeout %s seconds was reached" % request.timeout)
if reply[zmq_names.FIELD_FAILURE]:
raise rpc_common.deserialize_remote_exception(
reply[zmq_names.FIELD_FAILURE],
request.allowed_remote_exmods)
else:
return reply[zmq_names.FIELD_REPLY]
def close(self):
# For contextlib compatibility
self.cleanup()