Config options: Improve help text for console options

This commit adds additional help text to the config
options of the "nova/conf/console.py"

Change-Id: Ief69f0a6635f26a55f64edcb0f1ddffc85b14a36
Implements: blueprint centralize-config-options-newton

nova/conf/console.py

@@ -1,10 +1,3 @@
-# needs:fix_opt_description
-# needs:check_deprecation_status
-# needs:check_opt_group_and_type
-# needs:fix_opt_description_indentation
-# needs:fix_opt_registration_consistency
-
-
 # Copyright 2016 OpenStack Foundation
 # All Rights Reserved.
 #
@@ -28,17 +21,55 @@ from oslo_config import cfg
 console_opts = [
     cfg.ListOpt('console_allowed_origins',
                 default=[],
-                help='Allowed Origin header hostnames for access to console '
-                     'proxy servers'),
+                help="""
+Adds list of allowed origins to the console websocket proxy to allow
+connections from other origin hostnames.
+Websocket proxy matches the host header with the origin header to
+prevent cross-site requests. This list specifies if any there are
+values other than host are allowed in the origin header.
+
+Possible values
+
+  * An empty list (default) or list of allowed origin hostnames.
+"""),
+
+# TODO(pumaranikar): We can deprecate this option.
     cfg.StrOpt('console_topic',
                 default='console',
-                help='The topic console proxy nodes listen on'),
+                help="""
+Represents the message queue topic name used by nova-console
+service when communicating via the AMQP server. The Nova API uses a message
+queue to communicate with nova-console to retrieve a console URL for that
+host.
+
+Possible values
+
+  * 'console' (default) or any string representing topic exchange name.
+"""),
+
+# TODO(pumaranikar): Move this config to stevedoor plugin system.
     cfg.StrOpt('console_driver',
                 default='nova.console.xvp.XVPConsoleProxy',
-                help='Driver to use for the console proxy'),
+                help="""
+Nova-console proxy is used to set up multi-tenant VM console access.
+This option allows pluggable driver program for the console session
+and represents driver to use for the console proxy.
+
+Possible values
+
+  * 'nova.console.xvp.XVPConsoleProxy' (default) or
+    a string representing fully classified class name of console driver.
+"""),
+
     cfg.StrOpt('console_public_hostname',
                 default=socket.gethostname(),
-                help='Publicly visible name for this console host'),
+                help="""
+Publicly visible name for this console host.
+
+Possible values
+
+  * Current hostname (default) or any string representing hostname.
+"""),
 ]
 
 
@@ -46,5 +77,7 @@ def register_opts(conf):
     conf.register_opts(console_opts)
 
 
+# TODO(pumaranikar): We can consider moving these options to console group
+# and renaming them all to drop console bit.
 def list_opts():
     return {"DEFAULT": console_opts}