Add shim extension admin_state_down_before_update

Shim extension for neutron patch:
https://review.openstack.org/#/c/625134/
Adds releasenote.
Adds api-ref update.

Related-Bug: #1811166

Change-Id: Ie1167a9c7fc5dcb88a6955085937572805e41fd7
Signed-off-by: Matt Welch <matt.welch@intel.com>

api-ref/source/v2/routers.inc

@@ -52,6 +52,17 @@ Resource timestamps
 The ``standard-attr-timestamp`` extension adds the ``created_at`` and
 ``updated_at`` attributes to all resources that have standard attributes.
 
+Router admin state down before update extension
+===============================================
+
+The ``router-admin-state-down-before-update`` extension adds the requirement
+that the administrative state of a distributed virtual router (DVR) be set to
+DOWN (``admin_state_up=False``) prior to modifying the ``distributed``
+parameter of the router. The API will return an error response code of 400 if
+the router's ``distributed`` attribute is modified without first setting the
+router's ``admin_state_up=False``.
+This extension requires the ``dvr`` extension.
+
 Router availability zone extension
 ==================================
 

neutron_lib/api/definitions/__init__.py

@@ -81,6 +81,7 @@ from neutron_lib.api.definitions import qos_gateway_ip
 from neutron_lib.api.definitions import qos_rule_type_details
 from neutron_lib.api.definitions import qos_rules_alias
 from neutron_lib.api.definitions import revisionifmatch
+from neutron_lib.api.definitions import router_admin_state_down_before_update
 from neutron_lib.api.definitions import router_availability_zone
 from neutron_lib.api.definitions import router_interface_fip
 from neutron_lib.api.definitions import routerservicetype
@@ -178,6 +179,7 @@ _ALL_API_DEFINITIONS = {
     qos_rule_type_details,
     qos_rules_alias,
     revisionifmatch,
+    router_admin_state_down_before_update,
     router_availability_zone,
     router_interface_fip,
     routerservicetype,

neutron_lib/api/definitions/router_admin_state_down_before_update.py

@@ -0,0 +1,28 @@
+#    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 dvr as dvr_apidef
+
+ALIAS = 'router-admin-state-down-before-update'
+IS_SHIM_EXTENSION = True
+IS_STANDARD_ATTR_EXTENSION = False
+NAME = "Enforce Router's Admin State Down Before Update Extension"
+DESCRIPTION = ('Ensure that the admin state of a router is DOWN '
+               '(admin_state_up=False) before updating the distributed '
+               'attribute')
+UPDATED_TIMESTAMP = '2019-07-02T15:56:00'
+RESOURCE_ATTRIBUTE_MAP = {}
+SUB_RESOURCE_ATTRIBUTE_MAP = {}
+ACTION_MAP = {}
+REQUIRED_EXTENSIONS = [dvr_apidef.ALIAS]
+OPTIONAL_EXTENSIONS = []
+ACTION_STATUS = {}

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

@@ -0,0 +1,18 @@
+#    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 router_admin_state_down_before_update
+from neutron_lib.tests.unit.api.definitions import base
+
+
+class AdminStateDownToUpdateDefinitionTestCase(base.DefinitionBaseTestCase):
+    extension_module = router_admin_state_down_before_update

releasenotes/notes/admin-state-down-before-update-c06fb3a551fe499f.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - Router API is modified through a regime API extension to neutron-lib that
+    enforces the admin state of a router be DOWN (admin_state_up=False) prior
+    to modifying the distributed attribute of the router.