SmartObject

SmartObject is a library to easily manipulate object attributes with the API commands, store and synchronize object data.

SmartObject is designed to quickly build IoT applications, but can be used in any other applications, which require combining local and distributed object storages and changing object properties via external API calls, automatically validating incoming data.

Mapped object attributes (called properties) can be automatically validated, saved, loaded, serialized and synchronized with the external services.

SmartObject looks like ORM, but it’s different from ORM: object properties can be stored in storages of different type and combined together into a single data object.

SmartObject has built-in storage engines for files (JSON, YAML, MessagePack and CBOR) and databases: RDBMS via SQLAlchemy (can store objects) and Redis (can handle external properties only).

Property values are automatically processed, validated and synchronized with external services if required.

Note: all SmartObject methods are thread-safe (at least they should be :)

Example:

You have a team of people with heart-rate sensors. Data for each person is stored in local JSON files, heartbeat is stored in Redis database. How to implement this with SmartObject? Just a few lines of code:

import smartobject


class Person(smartobject.SmartObject):

    def __init__(self, name):
        self.name = name
        self.load_property_map('person.yml')
        self.apply_property_map()


smartobject.config.storage_dir = 'data'

smartobject.define_storage(smartobject.JSONStorage())
smartobject.define_storage(smartobject.RedisStorage(), 'r1')

people = smartobject.SmartObjectFactory(Person)

# create objects with factory
people.create(name='John')
people.create(name='Jane')

# create object manually
jack = Person('Jack')

# you can set a single prop
people.set_prop('John', 'sex', 'male')
people.set_prop('Jane', 'sex', 'female')
# or multiple props with dict
# heartbeat value is automatically written to Redis
jack.set_prop({'sex': 'male', 'heartbeat': 100})

# print object info (name and sex only)
from pprint import pprint
pprint(people.serialize('Jane', mode='info'))

people.save()
jack.save()

# clear Jack's sex
jack.set_prop('sex', None)
# load it back
jack.load()

# add Jack to factory
people.create(obj=jack)

# heartbeat value is automatically read from Redis
print('Heartbeat of Jack is: {}'.format(people.get('Jack').heartbeat))

The file person.yml is a property map for the Person object. It can be loaded from the external YAML file or specified directly, as Python dict.

The map for the above example looks like:

name:
    pk: true
    serialize: info
sex:
    type: str
    choices:
        - null
        - male
        - female
    store: true
    serialize: info
heartbeat:
    type: float
    external: true
    store: r1

Pretty simple, isn’t it? You define a map, SmartObject does the job!

Install

pip3 install smartobject