Make poll() just return the message

The driver shouldn't be pulling the namespace and version from the
message since that's RPC specific stuff.

Also, it's not terribly useful for the driver to pass back a target
object describing the exchange and topic the message was received on
since that's implicit in the listener.

openstack/common/messaging/_drivers/base.py

@@ -26,9 +26,7 @@ class Listener(object):
 
     @abc.abstractmethod
     def poll(self):
-        # returns (target, message)
+        # returns message
-        # target includes the (exchange, topic, namespace, version) which the
-        # message was sent to
         pass
 
     @abc.abstractmethod

openstack/common/messaging/_executors/base.py

@@ -30,9 +30,9 @@ class ExecutorBase(object):
         self.callback = callback
 
     def _process_one_message(self):
-        (target, message) = self.listener.poll()
+        message = self.listener.poll()
         try:
-            self.callback(target, message)
+            self.callback(message)
         except Exception:
             _LOG.exception(_("Failed to process message... skipping it."))
         finally:

openstack/common/messaging/rpc/dispatcher.py

@@ -57,15 +57,15 @@ class RPCDispatcher(object):
         endpoint_version = endpoint.target.version or '1.0'
         return utils.version_is_compatible(endpoint_version, version)
 
-    def __call__(self, target, message):
+    def __call__(self, message):
         method = message.get('method')
         args = message.get('args', {})
-
+        namespace = message.get('namespace')
-        version = target.version or '1.0'
+        version = message.get('version', '1.0')
 
         found_compatible = False
         for endpoint in self.endpoints:
-            if target.namespace != endpoint.target.namespace:
+            if namespace != endpoint.target.namespace:
                 continue
 
             is_compatible = self._is_compatible(endpoint, version)