Relocate AddressScope DB model

Required to resolve cyclic import issue when integrating with Oslo
Versioned Object for AddressScope

Change-Id: If57e472c5827033f09a59d1f8d9359a3f241c17c
Partial-Bug: #1597913

neutron/db/address_scope_db.py

@@ -12,29 +12,21 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import sys
+
 from neutron_lib import constants
 from oslo_utils import uuidutils
-import sqlalchemy as sa
 from sqlalchemy.orm import exc
 
 from neutron._i18n import _
 from neutron.api.v2 import attributes as attr
+from neutron.common import _deprecate
 from neutron.db import db_base_plugin_v2
-from neutron.db import model_base
+from neutron.db.models import address_scope as address_scope_model
 from neutron.extensions import address_scope as ext_address_scope
 from neutron.objects import subnetpool as subnetpool_obj
 
 
-class AddressScope(model_base.BASEV2, model_base.HasId, model_base.HasProject):
-    """Represents a neutron address scope."""
-
-    __tablename__ = "address_scopes"
-
-    name = sa.Column(sa.String(attr.NAME_MAX_LEN), nullable=False)
-    shared = sa.Column(sa.Boolean, nullable=False)
-    ip_version = sa.Column(sa.Integer(), nullable=False)
-
-
 class AddressScopeDbMixin(ext_address_scope.AddressScopePluginBase):
     """Mixin class to add address scope to db_base_plugin_v2."""
 
@@ -50,7 +42,8 @@ class AddressScopeDbMixin(ext_address_scope.AddressScopePluginBase):
 
     def _get_address_scope(self, context, id):
         try:
-            return self._get_by_id(context, AddressScope, id)
+            return self._get_by_id(context, address_scope_model.AddressScope,
+                                   id)
         except exc.NoResultFound:
             raise ext_address_scope.AddressScopeNotFound(address_scope_id=id)
 
@@ -83,7 +76,7 @@ class AddressScopeDbMixin(ext_address_scope.AddressScopePluginBase):
                          'name': a_s['name'],
                          'shared': a_s['shared'],
                          'ip_version': a_s['ip_version']}
-            address_scope = AddressScope(**pool_args)
+            address_scope = address_scope_model.AddressScope(**pool_args)
             context.session.add(address_scope)
 
         return self._make_address_scope_dict(address_scope)
@@ -108,7 +101,8 @@ class AddressScopeDbMixin(ext_address_scope.AddressScopePluginBase):
                            sorts=None, limit=None, marker=None,
                            page_reverse=False):
         marker_obj = self._get_marker_obj(context, 'addrscope', limit, marker)
-        collection = self._get_collection(context, AddressScope,
+        collection = self._get_collection(context,
+                                          address_scope_model.AddressScope,
                                           self._make_address_scope_dict,
                                           filters=filters, fields=fields,
                                           sorts=sorts,
@@ -118,7 +112,8 @@ class AddressScopeDbMixin(ext_address_scope.AddressScopePluginBase):
         return collection
 
     def get_address_scopes_count(self, context, filters=None):
-        return self._get_collection_count(context, AddressScope,
+        return self._get_collection_count(context,
+                                          address_scope_model.AddressScope,
                                           filters=filters)
 
     def delete_address_scope(self, context, id):
@@ -147,3 +142,10 @@ class AddressScopeDbMixin(ext_address_scope.AddressScopePluginBase):
 
     db_base_plugin_v2.NeutronDbPluginV2.register_dict_extend_funcs(
         attr.NETWORKS, ['_extend_network_dict_address_scope'])
+
+
+# WARNING: THESE MUST BE THE LAST TWO LINES IN THIS MODULE
+_OLD_REF = sys.modules[__name__]
+sys.modules[__name__] = _deprecate._DeprecateSubset(globals(),
+                                                    address_scope_model)
+# WARNING: THESE MUST BE THE LAST TWO LINES IN THIS MODULE

neutron/db/migration/models/head.py

@@ -24,7 +24,6 @@ Based on this comparison database can be healed with healing migration.
 import os.path
 
 from neutron.common import utils
-from neutron.db import address_scope_db  # noqa
 from neutron.db import agents_db  # noqa
 from neutron.db import agentschedulers_db  # noqa
 from neutron.db import dns_db  # noqa

neutron/db/models/address_scope.py

@@ -0,0 +1,26 @@
+#    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.
+
+import sqlalchemy as sa
+
+from neutron.api.v2 import attributes as attr
+from neutron.db import model_base
+
+
+class AddressScope(model_base.BASEV2, model_base.HasId, model_base.HasProject):
+    """Represents a neutron address scope."""
+
+    __tablename__ = "address_scopes"
+
+    name = sa.Column(sa.String(attr.NAME_MAX_LEN), nullable=False)
+    shared = sa.Column(sa.Boolean, nullable=False)
+    ip_version = sa.Column(sa.Integer(), nullable=False)

neutron/objects/address_scope.py

@@ -15,7 +15,7 @@
 from oslo_versionedobjects import base as obj_base
 from oslo_versionedobjects import fields as obj_fields
 
-from neutron.db import address_scope_db as models
+from neutron.db.models import address_scope as models
 from neutron.objects import base
 from neutron.objects import common_types