Add simple objects interface and registry

Objects are
- objects/bay
- objects/pod
- objects/service
- objects/container

These code is based on Solum.

Change-Id: Id1f64417a86807964ebb4226547517587d8565eb
Implements: blueprint db-object-definitions

magnum/objects/base.py

@@ -0,0 +1,53 @@
+# 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.
+
+
+class CrudMixin(object):
+
+    @classmethod
+    def get_by_id(cls, context, id):
+        """Return a specific object by its unique identifier."""
+
+    @classmethod
+    def get_by_uuid(cls, context, item_uuid):
+        """Return a specific object by its uuid."""
+
+    def create(self, context):
+        """Create the model."""
+
+    def save(self, context):
+        """Change the model."""
+
+    def destroy(self, context):
+        """Destroy the model."""
+
+    def add_forward_schema_changes(self):
+        """Update the attributes of self to include new schema elements.
+
+        This method is invoked during save/create operations to guarantee
+        that objects being created during a schema transition support both
+        new and old schemas.  This ensures that background jobs can run
+        to migrate existing objects on a live system while writes are
+        occurring.
+
+        The changes made by this method must match the schema defined
+        for "transitioning" and "new" (see solum.objects.__init__).
+        """
+
+
+class CrudListMixin(object):
+    @classmethod
+    def get_all(cls, context):
+        """Retrieve all applications for the active context.
+
+        Context may be global or tenant scoped.
+        """

magnum/objects/bay.py

@@ -0,0 +1,24 @@
+# Copyright 2014 NEC Corporation.  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.
+
+from magnum.objects import base
+
+
+class Bay(base.CrudMixin):
+    # Version 1.0: Initial version
+    VERSION = '1.0'
+
+
+class BayList(list, base.CrudListMixin):
+    """List of Bays."""

magnum/objects/container.py

@@ -0,0 +1,24 @@
+# Copyright 2014 NEC Corporation.  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.
+
+from magnum.objects import base
+
+
+class Container(base.CrudMixin):
+    # Version 1.0: Initial version
+    VERSION = '1.0'
+
+
+class ContainerList(list, base.CrudListMixin):
+    """List of Containers."""

magnum/objects/pod.py

@@ -0,0 +1,24 @@
+# Copyright 2014 NEC Corporation.  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.
+
+from magnum.objects import base
+
+
+class Pod(base.CrudMixin):
+    # Version 1.0: Initial version
+    VERSION = '1.0'
+
+
+class PodList(list, base.CrudListMixin):
+    """List of Pods."""

magnum/objects/registry.py

@@ -0,0 +1,29 @@
+#    Copyright 2013 Red Hat, Inc.
+#
+#    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.
+
+
+class Registry(object):
+    impls = dict()
+
+    """Allow domain objects to be loaded by name."""
+    def __getattr__(self, name):
+        return self.impls[name]
+
+    def add(self, interface, cls):
+        """Register an implementation for a class."""
+        self.impls[interface.__name__] = cls
+
+    def clear(self):
+        """Deregister all implementations."""
+        self.impls.clear()

magnum/objects/service.py

@@ -0,0 +1,24 @@
+# Copyright 2014 NEC Corporation.  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.
+
+from magnum.objects import base
+
+
+class Service(base.CrudMixin):
+    # Version 1.0: Initial version
+    VERSION = '1.0'
+
+
+class ServiceList(list, base.CrudListMixin):
+    """List of Services."""