oslo.versionedobjects/oslo_versionedobjects/examples/iot_bulb.py
Stephen Finucane 298c5107eb Bump to hacking 2.x
This allows us to use a new version of flake8 that supports Python
3-only syntax. Existing issues are resolved.

Change-Id: I5de7e5cde6a5260f4e7e57586952256b59d3756d
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>
2020-02-07 10:35:08 -08:00

62 lines
2.3 KiB
Python

# -*- coding: utf-8 -*-
# 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 datetime import datetime
from oslo_versionedobjects import base
from oslo_versionedobjects import fields as obj_fields
# INTRO: This example shows how a object (a plain-old-python-object) with
# some associated fields can be used, and some of its built-in methods can
# be used to convert that object into a primitive and back again (as well
# as determine simple changes on it.
# Ensure that we always register our object with an object registry,
# so that it can be deserialized from its primitive form.
@base.VersionedObjectRegistry.register
class IOTLightbulb(base.VersionedObject):
"""Simple light bulb class with some data about it."""
VERSION = '1.0' # Initial version
#: Namespace these examples will use.
OBJ_PROJECT_NAMESPACE = 'versionedobjects.examples'
#: Required fields this object **must** declare.
fields = {
'serial': obj_fields.StringField(),
'manufactured_on': obj_fields.DateTimeField(),
}
# Now do some basic operations on a light bulb.
bulb = IOTLightbulb(serial='abc-123', manufactured_on=datetime.now())
print("The __str__() output of this new object: %s" % bulb)
print("The 'serial' field of the object: %s" % bulb.serial)
bulb_prim = bulb.obj_to_primitive()
print("Primitive representation of this object: %s" % bulb_prim)
# Now convert the primitive back to an object (isn't it easy!)
bulb = IOTLightbulb.obj_from_primitive(bulb_prim)
bulb.obj_reset_changes()
print("The __str__() output of this new (reconstructed)"
" object: %s" % bulb)
# Mutating a field and showing what changed.
bulb.serial = 'abc-124'
print("After serial number change, the set of fields that"
" have been mutated is: %s" % bulb.obj_what_changed())