Add FIP64 extension from networking-midonet

This is a part of the stadium implosion effort. [1]

[1] https://review.openstack.org/#/c/389397/

Related-Bug: #1614477  (RFE bug)
Change-Id: I312ad95a46fc8b77cc7749a80ab0d61d6bb7aa4a

api-ref/source/v2/fip64.inc

@@ -0,0 +1,14 @@
+.. -*- rst -*-
+
+=====
+FIP64
+=====
+
+.. note:: Currently this extension ``fip64`` is only available for networking-midonet.
+
+This extension ``fip64`` provides
+`NAT64 <https://tools.ietf.org/html/rfc6146>`__
+functionality by allowing to associate IPv6 floating IPs to IPv4 fixed IPs.
+(Without this extension, floating IPs are limited to IPv4.)
+
+This extension does not introduce any resources or attributes.

api-ref/source/v2/index.rst

@@ -63,3 +63,7 @@ Logging Resource (networking-midonet)
 Router interface floating IP (networking-midonet)
 #################################################
 .. include:: router-interface-fip.inc
+##########################
+FIP64 (networking-midonet)
+##########################
+.. include:: fip64.inc

neutron_lib/api/definitions/fip64.py

@@ -0,0 +1,57 @@
+# All rights reserved.
+#
+#    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.
+
+from neutron_lib.api.definitions import l3
+
+# The alias of the extension.
+ALIAS = 'fip64'
+
+# Whether or not this extension is simply signaling behavior to the user
+# or it actively modifies the attribute map.
+IS_SHIM_EXTENSION = True
+
+# Whether the extension is marking the adoption of standardattr model for
+# legacy resources, or introducing new standardattr attributes. False or
+# None if the standardattr model is adopted since the introduction of
+# resource extension.
+# If this is True, the alias for the extension should be prefixed with
+# 'standard-attr-'.
+IS_STANDARD_ATTR_EXTENSION = False
+
+# The name of the extension.
+NAME = 'FIP64 Extension'
+
+# The description of the extension.
+DESCRIPTION = "FIP64 Extension"
+
+# A timestamp of when the extension was introduced.
+UPDATED_TIMESTAMP = "2016-12-14T10:00:00-00:00"
+
+# The resource attribute map for the extension. It is effectively the
+# bulk of the API contract alongside ACTION_MAP
+RESOURCE_ATTRIBUTE_MAP = {}
+
+# The subresource attribute map for the extension.
+SUB_RESOURCE_ATTRIBUTE_MAP = None
+
+# The action map.
+ACTION_MAP = {}
+
+# The list of required extensions.
+REQUIRED_EXTENSIONS = [
+    l3.ALIAS,
+]
+
+# The list of optional extensions.
+OPTIONAL_EXTENSIONS = []

neutron_lib/tests/unit/api/definitions/test_fip64.py

@@ -0,0 +1,20 @@
+#    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.
+
+from neutron_lib.api.definitions import fip64
+from neutron_lib.tests.unit.api.definitions import base
+
+
+class Fip64DefinitionTestCase(base.DefinitionBaseTestCase):
+    extension_module = fip64
+    extension_resources = ()
+    extension_attributes = ()

releasenotes/notes/fip64-0c6bb38417d602f1.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - API reference and definition for networking-midonet's ``fip64`` extension.