diff --git a/neutron/extensions/data_plane_status.py b/neutron/extensions/data_plane_status.py
index 8e225e670b5..dfaaa141de8 100644
--- a/neutron/extensions/data_plane_status.py
+++ b/neutron/extensions/data_plane_status.py
@@ -16,32 +16,5 @@ from neutron_lib.api.definitions import data_plane_status
 from neutron_lib.api import extensions
 
 
-class Data_plane_status(extensions.ExtensionDescriptor):
-
-    @classmethod
-    def get_name(cls):
-        return data_plane_status.NAME
-
-    @classmethod
-    def get_alias(cls):
-        return data_plane_status.ALIAS
-
-    @classmethod
-    def get_description(cls):
-        return data_plane_status.DESCRIPTION
-
-    @classmethod
-    def get_updated(cls):
-        return data_plane_status.UPDATED_TIMESTAMP
-
-    def get_required_extensions(self):
-        return data_plane_status.REQUIRED_EXTENSIONS or []
-
-    def get_optional_extensions(self):
-        return data_plane_status.OPTIONAL_EXTENSIONS or []
-
-    def get_extended_resources(self, version):
-        if version == "2.0":
-            return data_plane_status.RESOURCE_ATTRIBUTE_MAP
-        else:
-            return {}
+class Data_plane_status(extensions.APIExtensionDescriptor):
+    api_definition = data_plane_status
diff --git a/neutron/extensions/providernet.py b/neutron/extensions/providernet.py
index ae765890a28..5f7091f5189 100644
--- a/neutron/extensions/providernet.py
+++ b/neutron/extensions/providernet.py
@@ -33,7 +33,7 @@ def _raise_if_updates_provider_attributes(attrs):
         raise n_exc.InvalidInput(error_message=msg)
 
 
-class Providernet(extensions.ExtensionDescriptor):
+class Providernet(extensions.APIExtensionDescriptor):
     """Extension class supporting provider networks.
 
     This class is used by neutron's extension framework to make
@@ -45,25 +45,4 @@ class Providernet(extensions.ExtensionDescriptor):
     With admin rights, network dictionaries returned will also include
     provider attributes.
     """
-
-    @classmethod
-    def get_name(cls):
-        return provider_net.NAME
-
-    @classmethod
-    def get_alias(cls):
-        return provider_net.ALIAS
-
-    @classmethod
-    def get_description(cls):
-        return provider_net.DESCRIPTION
-
-    @classmethod
-    def get_updated(cls):
-        return provider_net.UPDATED_TIMESTAMP
-
-    def get_extended_resources(self, version):
-        if version == "2.0":
-            return provider_net.RESOURCE_ATTRIBUTE_MAP
-        else:
-            return {}
+    api_definition = provider_net
diff --git a/neutron/extensions/trunk.py b/neutron/extensions/trunk.py
index 07737435b2e..15d0ebcbf71 100644
--- a/neutron/extensions/trunk.py
+++ b/neutron/extensions/trunk.py
@@ -19,24 +19,9 @@ from neutron_lib.api import extensions
 from neutron.api.v2 import resource_helper
 
 
-class Trunk(extensions.ExtensionDescriptor):
+class Trunk(extensions.APIExtensionDescriptor):
     """Trunk API extension."""
-
-    @classmethod
-    def get_name(cls):
-        return trunk.NAME
-
-    @classmethod
-    def get_alias(cls):
-        return trunk.ALIAS
-
-    @classmethod
-    def get_description(cls):
-        return trunk.DESCRIPTION
-
-    @classmethod
-    def get_updated(cls):
-        return trunk.UPDATED_TIMESTAMP
+    api_definition = trunk
 
     @classmethod
     def get_resources(cls):
@@ -49,19 +34,3 @@ class Trunk(extensions.ExtensionDescriptor):
             trunk.ALIAS,
             action_map=trunk.ACTION_MAP,
             register_quota=True)
-
-    def update_attributes_map(self, attributes, extension_attrs_map=None):
-        super(Trunk, self).update_attributes_map(
-            attributes, extension_attrs_map=trunk.RESOURCE_ATTRIBUTE_MAP)
-
-    def get_required_extensions(self):
-        return trunk.REQUIRED_EXTENSIONS or []
-
-    def get_optional_extensions(self):
-        return trunk.OPTIONAL_EXTENSIONS or []
-
-    def get_extended_resources(self, version):
-        if version == "2.0":
-            return trunk.RESOURCE_ATTRIBUTE_MAP
-        else:
-            return {}
diff --git a/neutron/extensions/trunk_details.py b/neutron/extensions/trunk_details.py
index 4bb5a68f763..ea5abbc7e2c 100644
--- a/neutron/extensions/trunk_details.py
+++ b/neutron/extensions/trunk_details.py
@@ -23,32 +23,5 @@ from neutron_lib.api import extensions
 # config-drive configuration.
 
 
-class Trunk_details(extensions.ExtensionDescriptor):
-
-    @classmethod
-    def get_name(cls):
-        return trunk_details.NAME
-
-    @classmethod
-    def get_alias(cls):
-        return trunk_details.ALIAS
-
-    @classmethod
-    def get_description(cls):
-        return trunk_details.DESCRIPTION
-
-    @classmethod
-    def get_updated(cls):
-        return trunk_details.TIMESTAMP
-
-    def get_required_extensions(self):
-        return trunk_details.REQUIRED_EXTENSIONS or []
-
-    def get_optional_extensions(self):
-        return trunk_details.OPTIONAL_EXTENSIONS or []
-
-    def get_extended_resources(self, version):
-        if version == "2.0":
-            return trunk_details.RESOURCE_ATTRIBUTE_MAP
-        else:
-            return {}
+class Trunk_details(extensions.APIExtensionDescriptor):
+    api_definition = trunk_details
diff --git a/neutron/tests/tools.py b/neutron/tests/tools.py
index ba2dc6c956c..f9d0ca154ec 100644
--- a/neutron/tests/tools.py
+++ b/neutron/tests/tools.py
@@ -25,6 +25,7 @@ import fixtures
 import mock
 import netaddr
 from neutron_lib import constants
+from neutron_lib import fixture
 from neutron_lib.utils import helpers
 from neutron_lib.utils import net
 from oslo_utils import netutils
@@ -37,7 +38,7 @@ from neutron.plugins.common import constants as p_const
 from neutron.services.logapi.common import constants as log_const
 
 
-class AttributeMapMemento(fixtures.Fixture):
+class AttributeMapMemento(fixture.APIDefinitionFixture):
     """Create a copy of the resource attribute map so it can be restored during
     test cleanup.
 
@@ -53,6 +54,8 @@ class AttributeMapMemento(fixtures.Fixture):
     """
 
     def _setUp(self):
+        self.backup_global_resources = False
+        super(AttributeMapMemento, self)._setUp()
         # Shallow copy is not a proper choice for keeping a backup copy as
         # the RESOURCE_ATTRIBUTE_MAP map is modified in place through the
         # 0th level keys. Ideally deepcopy() would be used but this seems
@@ -64,6 +67,7 @@ class AttributeMapMemento(fixtures.Fixture):
         self.addCleanup(self.restore)
 
     def restore(self):
+        super(AttributeMapMemento, self)._restore()
         attributes.RESOURCE_ATTRIBUTE_MAP = self.contents_backup