def _process_data(self, data): result = None self.msg_id_cache.check_duplicate_message(data) if data['failure']: failure = data['failure'] result = rpc_common.deserialize_remote_exception(self._conf, failure) elif data.get('ending', False): self._got_ending = True else: result = data['result'] return result
def _call(addr, context, topic, msg, timeout=None, envelope=False): # 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")) _cast(addr, context, topic, payload, envelope) LOG.debug(_("Cast sent; Waiting reply")) # Blocks until receives reply msg = msg_waiter.recv() 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(CONF, resp['exc']) return responses[-1]