Allow sub-resources to have standard attributes

Prior to this change a DB model with standard
attributes could declare that it was mapping to
an API resource, but not declare a mapping to a
sub-resources (see bug 1763347).

This change allows DB models with standard attributes
to advertise that they map API *sub*-resources, and
modifies the code that extends DB resources to support
these specific declarations.

Closes-Bug: 1763347
Needed-By: I77ce46c0f33e2a366076d51ce6586fb3008dc6b1

Change-Id: I7630aab5e4f38d0fba862adc2426d4a7ca04a679

neutron/db/standard_attr.py

@@ -98,6 +98,22 @@ class HasStandardAttributes(object):
             return cls.api_collections
         raise NotImplementedError("%s must define api_collections" % cls)
 
+    @classmethod
+    def get_api_sub_resources(cls):
+        """Define the API sub-resources this object will appear under.
+
+        This should return a list of API sub-resources that the object
+        will be exposed under.
+
+        This is used by the standard attr extensions to discover which
+        sub-resources need to be extended with the standard attr fields
+        (e.g. created_at/updated_at/etc).
+        """
+        try:
+            return cls.api_sub_resources
+        except AttributeError:
+            return []
+
     @classmethod
     def get_collection_resource_map(cls):
         try:
@@ -173,17 +189,26 @@ class HasStandardAttributes(object):
         self.standard_attr.bump_revision()
 
 
-def get_standard_attr_resource_model_map():
+def _resource_model_map_helper(rs_map, resource, subclass):
+    if resource in rs_map:
+        raise RuntimeError("Model %(sub)s tried to register for API resource "
+                           "%(res)s which conflicts with model %(other)s." %
+                           dict(sub=subclass,
+                                other=rs_map[resource],
+                                res=resource))
+    rs_map[resource] = subclass
+
+
+def get_standard_attr_resource_model_map(include_resources=True,
+                                         include_sub_resources=True):
     rs_map = {}
     for subclass in HasStandardAttributes.__subclasses__():
-        for resource in subclass.get_api_collections():
-            if resource in rs_map:
-                raise RuntimeError("Model %(sub)s tried to register for "
-                                   "API resource %(res)s which conflicts "
-                                   "with model %(other)s." %
-                                   dict(sub=subclass, other=rs_map[resource],
-                                        res=resource))
-            rs_map[resource] = subclass
+        if include_resources:
+            for resource in subclass.get_api_collections():
+                _resource_model_map_helper(rs_map, resource, subclass)
+        if include_sub_resources:
+            for sub_resource in subclass.get_api_sub_resources():
+                _resource_model_map_helper(rs_map, sub_resource, subclass)
     return rs_map
 
 

neutron/extensions/revisions.py

@@ -13,7 +13,7 @@
 
 from neutron_lib.api import extensions
 
-from neutron.db import standard_attr
+from neutron.extensions import stdattrs_common
 
 
 REVISION = 'revision_number'
@@ -46,5 +46,4 @@ class Revisions(extensions.ExtensionDescriptor):
     def get_extended_resources(self, version):
         if version != "2.0":
             return {}
-        rs_map = standard_attr.get_standard_attr_resource_model_map()
-        return {resource: REVISION_BODY for resource in rs_map}
+        return stdattrs_common.stdattrs_extended_resources(REVISION_BODY)

neutron/extensions/standardattrdescription.py

@@ -16,7 +16,7 @@
 from neutron_lib.api import extensions
 from neutron_lib.db import constants as db_const
 
-from neutron.db import standard_attr
+from neutron.extensions import stdattrs_common
 
 
 DESCRIPTION_BODY = {
@@ -51,5 +51,4 @@ class Standardattrdescription(extensions.ExtensionDescriptor):
     def get_extended_resources(self, version):
         if version != "2.0":
             return {}
-        rs_map = standard_attr.get_standard_attr_resource_model_map()
-        return {resource: DESCRIPTION_BODY for resource in rs_map}
+        return stdattrs_common.stdattrs_extended_resources(DESCRIPTION_BODY)

neutron/extensions/stdattrs_common.py

@@ -0,0 +1,31 @@
+# Copyright (c) 2018 Orange.
+# 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.
+
+import itertools
+
+from neutron.db import standard_attr
+
+
+def stdattrs_extended_resources(attributes):
+    r_map = standard_attr.get_standard_attr_resource_model_map(
+        include_resources=True,
+        include_sub_resources=False)
+    sr_map = standard_attr.get_standard_attr_resource_model_map(
+        include_resources=False,
+        include_sub_resources=True)
+    return dict(itertools.chain(
+        {r: attributes for r in r_map}.items(),
+        {sr: {'parameters': attributes} for sr in sr_map}.items()
+    ))

neutron/extensions/timestamp.py

@@ -14,7 +14,7 @@
 
 from neutron_lib.api import extensions
 
-from neutron.db import standard_attr
+from neutron.extensions import stdattrs_common
 
 
 # Attribute Map
@@ -57,5 +57,4 @@ class Timestamp(extensions.ExtensionDescriptor):
     def get_extended_resources(self, version):
         if version != "2.0":
             return {}
-        rs_map = standard_attr.get_standard_attr_resource_model_map()
-        return {resource: TIMESTAMP_BODY for resource in rs_map}
+        return stdattrs_common.stdattrs_extended_resources(TIMESTAMP_BODY)

neutron/tests/unit/db/test_standard_attr.py

@@ -42,10 +42,26 @@ class StandardAttrTestCase(base.BaseTestCase):
                       standard_attr.model_base.HasId,
                       base):
             api_collections = ['my_resource', 'my_resource2']
+            api_sub_resources = ['my_subresource']
 
         rs_map = standard_attr.get_standard_attr_resource_model_map()
         self.assertEqual(MyModel, rs_map['my_resource'])
         self.assertEqual(MyModel, rs_map['my_resource2'])
+        self.assertEqual(MyModel, rs_map['my_subresource'])
+
+        sub_rs_map = standard_attr.get_standard_attr_resource_model_map(
+            include_resources=False,
+            include_sub_resources=True)
+        self.assertNotIn('my_resource', sub_rs_map)
+        self.assertNotIn('my_resource2', sub_rs_map)
+        self.assertEqual(MyModel, sub_rs_map['my_subresource'])
+
+        nosub_rs_map = standard_attr.get_standard_attr_resource_model_map(
+            include_resources=True,
+            include_sub_resources=False)
+        self.assertEqual(MyModel, nosub_rs_map['my_resource'])
+        self.assertEqual(MyModel, nosub_rs_map['my_resource2'])
+        self.assertNotIn('my_subresource', nosub_rs_map)
 
         class Dup(standard_attr.HasStandardAttributes,
                   standard_attr.model_base.HasId,