Add entry points for option discovery

Create entry points for oslo.policy, and make the necessary
changes to grouping the options into a new 'oslo_policy' group.

Change-Id: I32fd78c8a90fd2d49824db145362069b81fcaec5
Closes-Bug: #1415631

1 files changed, 36 insertions, 0 deletions

diff --git a/oslo_policy/opts.py b/oslo_policy/opts.py
new file mode 100644
index 0000000..8191449
--- /dev/null
+++ b/oslo_policy/opts.py
@@ -0,0 +1,36 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+__all__ = [
+    'list_opts'
+]
+
+import copy
+
+from oslo_policy import policy
+
+
+def list_opts():
+    """Return a list of oslo.config options available in the library.
+    The returned list includes all oslo.config options which may be registered
+    at runtime by the library.
+    Each element of the list is a tuple. The first element is the name of the
+    group under which the list of elements in the second element will be
+    registered. A group name of None corresponds to the [DEFAULT] group in
+    config files.
+    This function is also discoverable via the 'oslo_messaging' entry point
+    under the 'oslo.config.opts' namespace.
+    The purpose of this is to allow tools like the Oslo sample config file
+    generator to discover the options exposed to users by this library.
+    :returns: a list of (group_name, opts) tuples
+    """
+    return [('oslo_policy', copy.deepcopy(policy._opts))]