Add support to regenerate port mac_address

- Adds converter to generate a valid mac address if the
  provided data is 'null' (None).
- Adds api extension definition for port using the new converter.

Related-Bug: #1768690
Change-Id: Ibfcf179c2051d2bf47d4d1e62e8146cbee29fd64

api-ref/source/v2/ports.inc

@@ -96,6 +96,14 @@ define QoS policies and associate these to the ports by introducing the
 ``qos_policy_id`` attribute. The policies should be created before they are
 associated to the ports.
 
+Regenerate mac address extension
+================================
+
+The Port MAC address regenerate extension (``port-mac-address-regenerate``)
+makes it possible to regenerate the mac address of a port. When passing
+``'null'`` (``None``) as the ``mac_address`` on port update, a new mac address
+will be generated and set on the port.
+
 Resource timestamps
 ===================
 

neutron_lib/api/converters.py

@@ -11,6 +11,7 @@
 #    under the License.
 
 import netaddr
+from oslo_config import cfg
 from oslo_utils import strutils
 import six
 
@@ -18,6 +19,7 @@ from neutron_lib._i18n import _
 from neutron_lib.api import validators
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.utils import net as net_utils
 
 
 def convert_to_boolean(data):
@@ -306,3 +308,15 @@ def convert_uppercase_ip(data):
               the return value is data with the first two letter uppercased
     """
     return convert_prefix_forced_case(data, "IP")
+
+
+def convert_to_mac_if_none(data):
+    """Convert to a random mac address if data is None
+
+    :param data: The data value
+    :return: Random mac address if data is None, else return data.
+    """
+    if data is None:
+        return net_utils.get_random_mac(cfg.CONF.base_mac.split(':'))
+
+    return data

neutron_lib/api/definitions/__init__.py

@@ -59,6 +59,7 @@ from neutron_lib.api.definitions import network_mtu
 from neutron_lib.api.definitions import network_mtu_writable
 from neutron_lib.api.definitions import pagination
 from neutron_lib.api.definitions import port
+from neutron_lib.api.definitions import port_mac_address_regenerate
 from neutron_lib.api.definitions import port_security
 from neutron_lib.api.definitions import portbindings
 from neutron_lib.api.definitions import portbindings_extended
@@ -141,6 +142,7 @@ _ALL_API_DEFINITIONS = {
     network_mtu_writable,
     pagination,
     port,
+    port_mac_address_regenerate,
     port_security,
     portbindings,
     portbindings_extended,

neutron_lib/api/definitions/port.py

@@ -24,6 +24,8 @@ UPDATED_TIMESTAMP = "2012-01-01T10:00:00-00:00"
 RESOURCE_NAME = 'port'
 COLLECTION_NAME = 'ports'
 
+PORT_MAC_ADDRESS = 'mac_address'
+
 RESOURCE_ATTRIBUTE_MAP = {
     COLLECTION_NAME: {
         'id': {'allow_post': False, 'allow_put': False,
@@ -50,13 +52,13 @@ RESOURCE_ATTRIBUTE_MAP = {
                            'is_filter': True,
                            'is_sort_key': True,
                            'is_visible': True},
-        'mac_address': {'allow_post': True, 'allow_put': True,
-                        'default': constants.ATTR_NOT_SPECIFIED,
-                        'validate': {'type:mac_address': None},
-                        'enforce_policy': True,
-                        'is_filter': True,
-                        'is_sort_key': True,
-                        'is_visible': True},
+        PORT_MAC_ADDRESS: {'allow_post': True, 'allow_put': True,
+                           'default': constants.ATTR_NOT_SPECIFIED,
+                           'validate': {'type:mac_address': None},
+                           'enforce_policy': True,
+                           'is_filter': True,
+                           'is_sort_key': True,
+                           'is_visible': True},
         'fixed_ips': {'allow_post': True, 'allow_put': True,
                       'default': constants.ATTR_NOT_SPECIFIED,
                       'convert_list_to':

neutron_lib/api/definitions/port_mac_address_regenerate.py

@@ -0,0 +1,42 @@
+#    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 import converters
+from neutron_lib.api.definitions import port as port_def
+from neutron_lib import constants
+
+
+NAME = 'Neutron Port MAC address regenerate'
+ALIAS = 'port-mac-address-regenerate'
+DESCRIPTION = "Network port MAC address regenerate"
+
+UPDATED_TIMESTAMP = "2018-05-03T10:00:00-00:00"
+
+RESOURCE_ATTRIBUTE_MAP = {
+    port_def.COLLECTION_NAME: {
+        port_def.PORT_MAC_ADDRESS: {
+            'allow_post': True, 'allow_put': True,
+            'default': constants.ATTR_NOT_SPECIFIED,
+            'convert_to': converters.convert_to_mac_if_none,
+            'validate': {'type:mac_address': None},
+            'enforce_policy': True,
+            'is_visible': True},
+    }
+}
+
+IS_SHIM_EXTENSION = False
+IS_STANDARD_ATTR_EXTENSION = False
+SUB_RESOURCE_ATTRIBUTE_MAP = {}
+ACTION_MAP = {}
+REQUIRED_EXTENSIONS = []
+OPTIONAL_EXTENSIONS = []
+ACTION_STATUS = {}

neutron_lib/tests/unit/api/definitions/test_port_mac_address_regenerate.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 port as port_def
+from neutron_lib.api.definitions import port_mac_address_regenerate
+from neutron_lib.tests.unit.api.definitions import base
+
+
+class PortMacAddressRegenerateTestCase(base.DefinitionBaseTestCase):
+    extension_module = port_mac_address_regenerate
+    extension_attributes = (port_def.PORT_MAC_ADDRESS,)

neutron_lib/tests/unit/api/test_conversions.py

@@ -13,6 +13,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import mock
+import netaddr
 import six
 import testtools
 
@@ -331,3 +333,17 @@ class TestConvertUppercasePrefix(base.BaseTestCase):
         self.assertEqual('fo',
                          converters.convert_prefix_forced_case('fo',
                                                                'foo'))
+
+
+class TestConvertPortMacAddress(base.BaseTestCase):
+
+    def test_mac_address_does_not_convert(self):
+        valid_mac = 'fa:16:3e:b6:78:1f'
+        self.assertEqual(valid_mac,
+                         converters.convert_to_mac_if_none(valid_mac))
+
+    @mock.patch('oslo_config.cfg.CONF')
+    def test_convert_none_to_mac_address(self, CONF):
+        CONF.base_mac = 'fa:16:3e:00:00:00'
+        self.assertTrue(
+            netaddr.valid_mac(converters.convert_to_mac_if_none(None)))

releasenotes/notes/port-mac-address-regenerate-cc33d03216b5bc3d.yaml

@@ -0,0 +1,9 @@
+---
+features:
+  - |
+    Adds api extension ``port-mac-address-regenerate``. Also adds converter
+    ``convert_to_mac_if_none`` used by api extenstion
+    ``port-mac-address-regenerate``. When passing ``'null'`` (``None``) as the
+    ``mac_address`` on port update the converter will generate a new mac
+    address that will be assigned to the port.
+    `RFE:  #1768690 <https://bugs.launchpad.net/neutron/+bug/1768690>`_.