def _multi_send(driver,
method,
context,
topic,
msg,
timeout=None,
envelope=False,
_msg_id=None,
allowed_remote_exmods=None,
pooled=False):
"""Wraps the sending of messages.
Dispatches to the matchmaker and sends message to all relevant hosts.
"""
allowed_remote_exmods = allowed_remote_exmods or []
conf = CONF
LOG.debug(' '.join(map(pformat, (topic, msg))))
queues = _get_matchmaker().queues(topic)
LOG.debug("Sending message(s) to: %s", queues)
# Don't stack if we have no matchmaker results
if not queues:
warn_log = _LW("No matchmaker results. Not sending.")
if method.__name__ == '_cast':
LOG.warn(warn_log)
return
# While not strictly a timeout, callers know how to handle
# this exception and a timeout isn't too big a lie.
raise rpc_common.Timeout(warn_log)
# This supports brokerless fanout (addresses > 1)
return_val = None
for queue in queues:
_topic, ip_addr = queue
_addr = "tcp://%s:%s" % (ip_addr, conf.rpc_zmq_port)
if method.__name__ == '_cast':
eventlet.spawn_n(method, driver, _addr, context, _topic, msg,
timeout, envelope, _msg_id, None, pooled)
else:
return_val = method(driver, _addr, context, _topic, msg, timeout,
envelope, allowed_remote_exmods, pooled)
return return_val
def _raise_timeout(exc):
LOG.debug('Timed out waiting for RPC response: %s', exc)
raise rpc_common.Timeout()
def _raise_timeout(exc):
raise driver_common.Timeout(exc.message)
def _raise_timeout():
LOG.debug('Timed out waiting for Kafka response')
raise driver_common.Timeout()
def _raise_timeout(exc):
raise driver_common.Timeout(str(exc))
def _call(addr,
context,
topic,
msg,
timeout=None,
envelope=False,
allowed_remote_exmods=None):
allowed_remote_exmods = allowed_remote_exmods or []
# timeout_response is how long we wait for a response
timeout = timeout or CONF.rpc_response_timeout
# The msg_id is used to track replies.
msg_id = uuid.uuid4().hex
# Replies always come into the reply service.
reply_topic = "zmq_replies.%s" % CONF.rpc_zmq_host
LOG.debug("Creating payload")
# Curry the original request into a reply method.
mcontext = RpcContext.marshal(context)
payload = {
'method': '-reply',
'args': {
'msg_id': msg_id,
'topic': reply_topic,
# TODO(ewindisch): safe to remove mcontext in I.
'msg': [mcontext, msg]
}
}
LOG.debug("Creating queue socket for reply waiter")
# Messages arriving async.
# TODO(ewindisch): have reply consumer with dynamic subscription mgmt
with Timeout(timeout, exception=rpc_common.Timeout):
try:
msg_waiter = ZmqSocket("ipc://%s/zmq_topic_zmq_replies.%s" %
(CONF.rpc_zmq_ipc_dir, CONF.rpc_zmq_host),
zmq.SUB,
subscribe=msg_id,
bind=False)
LOG.debug("Sending cast: %s", topic)
_cast(addr, context, topic, payload, envelope=envelope)
LOG.debug("Cast sent; Waiting reply")
# Blocks until receives reply
msg = msg_waiter.recv()
if msg is None:
raise rpc_common.Timeout()
LOG.debug("Received message: %s", msg)
LOG.debug("Unpacking response")
if msg[2] == 'cast': # Legacy version
raw_msg = _deserialize(msg[-1])[-1]
elif msg[2] == 'impl_zmq_v2':
rpc_envelope = unflatten_envelope(msg[4:])
raw_msg = rpc_common.deserialize_msg(rpc_envelope)
else:
raise rpc_common.UnsupportedRpcEnvelopeVersion(
_("Unsupported or unknown ZMQ envelope returned."))
responses = raw_msg['args']['response']
# ZMQError trumps the Timeout error.
except zmq.ZMQError:
raise RPCException("ZMQ Socket Error")
except (IndexError, KeyError):
raise RPCException(_("RPC Message Invalid."))
finally:
if 'msg_waiter' in vars():
msg_waiter.close()
# It seems we don't need to do all of the following,
# but perhaps it would be useful for multicall?
# One effect of this is that we're checking all
# responses for Exceptions.
for resp in responses:
if isinstance(resp, types.DictType) and 'exc' in resp:
raise rpc_common.deserialize_remote_exception(
resp['exc'], allowed_remote_exmods)
return responses[-1]
