Add common messaging attributes

Similar to the way in which we handle database attributes, provide a
mechanism that allows for centralized messaging configuration. Right
now this supports rabbit, but there is no reason other message queues
could not be added in the default['openstack']['mq'] namespace.

Change-Id: Id9d34fa7c256920dd575eee57c7b3820dacf8068

CHANGELOG.md

@@ -12,6 +12,7 @@ This file is used to list changes made in each version of cookbook-openstack-com
 * Added `#address_for` method, which returns the IPv4 (default) address of the given
   interface.
 * Added global mysql setting of port and db type, for use with wrapper cookbooks.
+* Add default messaging attributes, for use with wrapper cookbooks.
 
 ## 0.2.6:
 * Update Chef dependency to Chef 11.

attributes/default.rb

@@ -309,5 +309,11 @@ default['openstack']['db']['root_user_key'] = 'mysqlroot'
 default['openstack']['logging']['ignore'] = {'nova.api.openstack.wsgi' => 'WARNING',
                                              'nova.osapi_compute.wsgi.server' => 'WARNING'}
 
-# override search for memcached_servers by setting this attribute
 default['openstack']['memcached_servers'] = nil
+
+# Default database attributes
+default["openstack"]["mq"]["server_role"] = "os-ops-messaging"
+default["openstack"]["mq"]["service_type"] = "rabbitmq"
+default["openstack"]["mq"]["port"] = "5672"
+default["openstack"]["mq"]["user"] = "guest"
+default["openstack"]["mq"]["vhost"] = "/"