Support to generate config sample file

Change-Id: Ic9dc4630dd96227eb8a655c3aac223316d5a060e

doc/source/admin/run_trove_in_production.rst

@@ -150,8 +150,16 @@ guest instance doesn't affect other instances nor other cloud users.
 
 Configuring Trove
 ~~~~~~~~~~~~~~~~~
-The default Trove configuration file location is ``/etc/trove/trove.conf``. The
-typical config options (not a full list) are:
+The default Trove configuration file location is ``/etc/trove/trove.conf``. You
+can generate a sample config file by running:
+
+.. code-block:: console
+
+    cd <trove dir>
+    pip install -e .
+    oslo-config-generator --namespace trove.config --namespace oslo.messaging --namespace oslo.log --namespace oslo.log oslo.policy --output-file /etc/trove/trove.conf.sample
+
+The typical config options (not a full list) are:
 
 DEFAULT group
   enable_secure_rpc_messaging

setup.cfg

@@ -58,3 +58,6 @@ oslo.policy.policies =
     # list_rules method into a separate entry point rather than using the
     # aggregate method.
     trove = trove.common.policies:list_rules
+
+oslo.config.opts =
+    trove.config = trove.common.cfg:list_opts

trove/common/cfg.py

@@ -17,9 +17,11 @@
 
 import os.path
 
+from keystoneauth1 import loading
+from keystonemiddleware import auth_token
 from oslo_config import cfg
-from oslo_config.cfg import NoSuchOptError
 from oslo_config import types
+from oslo_config.cfg import NoSuchOptError
 from oslo_log import log as logging
 from oslo_middleware import cors
 from osprofiler import opts as profiler
@@ -1470,6 +1472,24 @@ profiler.set_defaults(CONF)
 logging.register_options(CONF)
 
 
+def list_opts():
+    keystone_middleware_opts = auth_token.list_opts()
+    keystone_loading_opts = [(
+        'keystone_authtoken', loading.get_auth_plugin_conf_options('password')
+    )]
+
+    trove_opts = [
+        (None, path_opts + versions_opts + common_opts),
+        ('database', database_opts),
+        (mysql_group, mysql_opts),
+        (mariadb_group, mariadb_opts),
+        (network_group, network_opts),
+        (service_credentials_group, service_credentials_opts),
+    ]
+
+    return keystone_middleware_opts + keystone_loading_opts + trove_opts
+
+
 def custom_parser(parsername, parser):
     CONF.register_cli_opt(cfg.SubCommandOpt(parsername, handler=parser))