Improve proxy publish method

Added possibility to send a message to multiple routing keys
without having to create new connection for each send.

Change-Id: Ie23cfd130996b693c091e164043d80f35f04d694

taskflow/engines/worker_based/executor.py

@@ -169,8 +169,7 @@ class WorkerTaskExecutor(executor.TaskExecutorBase):
         """Cyclically publish notify message to each topic."""
         LOG.debug("Notify thread started.")
         while not self._notify_event.is_set():
-            for topic in self._topics:
-                self._proxy.publish(pr.Notify(), topic, reply_to=self._uuid)
+            self._proxy.publish(pr.Notify(), self._topics, reply_to=self._uuid)
             self._notify_event.wait(pr.NOTIFY_PERIOD)
 
     def execute_task(self, task, task_uuid, arguments,

taskflow/engines/worker_based/proxy.py

@@ -19,6 +19,8 @@ import logging
 import socket
 import threading
 
+import six
+
 LOG = logging.getLogger(__name__)
 
 # NOTE(skudriashev): A timeout of 1 is often used in environments where
@@ -67,14 +69,19 @@ class Proxy(object):
 
     def publish(self, msg, routing_key, **kwargs):
         """Publish message to the named exchange with routing key."""
+        if isinstance(routing_key, six.string_types):
+            routing_keys = [routing_key]
+        else:
+            routing_keys = routing_key
         with kombu.producers[self._conn].acquire(block=True) as producer:
-            queue = self._make_queue(routing_key, self._exchange)
-            producer.publish(body=msg.to_dict(),
-                             routing_key=routing_key,
-                             exchange=self._exchange,
-                             declare=[queue],
-                             type=msg.TYPE,
-                             **kwargs)
+            for routing_key in routing_keys:
+                queue = self._make_queue(routing_key, self._exchange)
+                producer.publish(body=msg.to_dict(),
+                                 routing_key=routing_key,
+                                 exchange=self._exchange,
+                                 declare=[queue],
+                                 type=msg.TYPE,
+                                 **kwargs)
 
     def start(self):
         """Start proxy."""