Enable Magnum to send notifications via RPC

Initialize RPC notification transport on starting magnum-api and
magnum-conductor. Here is the initialization sequence:
1. magnum.cmd.api.main()/magnum.cmd.conductor.main()
2. magnum.common.service.prepare_service()
3. magnum.common.config.parse_args()
4. magnum.common.rpc.init()
The last call setup a notifier that can be used to send notifications
via message queue.

Change-Id: Ibcc88d74a933d55ff33fad55e603786f9b4a3906
Partially-Implements: blueprint autoscale-bay

etc/magnum/magnum.conf.sample

@@ -35,6 +35,12 @@
 # (integer value)
 #periodic_interval_max = 60
 
+# Name of this node.  This can be an opaque identifier. It is not
+# necessarily a hostname, FQDN, or IP address. However, the node name
+# must be valid within an AMQP key, and if using ZeroMQ, a valid
+# hostname, FQDN, or IP address. (string value)
+#host = localhost
+
 #
 # From oslo.log
 #

magnum/common/rpc.py

@@ -141,7 +141,7 @@ def get_server(target, endpoints, serializer=None):
                                     serializer=serializer)
 
 
-def get_notifier(service=None, host=None, publisher_id=None):
+def get_notifier(service='container', host=None, publisher_id=None):
     assert NOTIFIER is not None
     if not publisher_id:
         publisher_id = "%s.%s" % (service, host or CONF.host)

magnum/common/service.py

@@ -12,13 +12,31 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import socket
+
 from oslo_config import cfg
 from oslo_log import log as logging
 
+from magnum.common import config
+from magnum.i18n import _
+
+
+service_opts = [
+    cfg.StrOpt('host',
+               default=socket.getfqdn(),
+               help=_('Name of this node. This can be an opaque identifier. '
+                      'It is not necessarily a hostname, FQDN, or IP address. '
+                      'However, the node name must be valid within '
+                      'an AMQP key, and if using ZeroMQ, a valid '
+                      'hostname, FQDN, or IP address.')),
+]
+
+cfg.CONF.register_opts(service_opts)
+
 
 def prepare_service(argv=None):
     if argv is None:
         argv = []
     logging.register_options(cfg.CONF)
-    cfg.CONF(argv[1:], project='magnum')
+    config.parse_args(argv)
     logging.setup(cfg.CONF, 'magnum')

magnum/opts.py

@@ -20,6 +20,7 @@ import magnum.api.auth
 import magnum.common.clients
 import magnum.common.exception
 import magnum.common.magnum_keystoneclient
+import magnum.common.service
 import magnum.conductor.config
 import magnum.conductor.handlers.bay_conductor
 import magnum.conductor.handlers.docker_conductor
@@ -35,7 +36,8 @@ def list_opts():
                          magnum.common.magnum_keystoneclient.trust_opts,
                          magnum.common.paths.PATH_OPTS,
                          magnum.common.utils.UTILS_OPTS,
-                         magnum.common.rpc_service.periodic_opts
+                         magnum.common.rpc_service.periodic_opts,
+                         magnum.common.service.service_opts,
                          )),
         ('api', magnum.api.app.API_SERVICE_OPTS),
         ('bay', magnum.conductor.template_definition.template_def_opts),