This is a pre-production deployment of Warehouse. Changes made here affect the production instance of PyPI (pypi.python.org).
Help us improve Python packaging - Donate today!

declarative de/serialization of python structures

Project Description

As a result of frustration working with colander, I decided to create something similar…

Objective is a de/serialization tool with following features:

  • declarative definition of objectives.
  • no confusion about how to define something, it is always the same.
  • reuse definitions by inheritance.
  • optional validation.
  • make it simple to override certain parts.

Usage

Simple mapping and validation

import objective
import datetime


now = datetime.datetime(2001, 9, 11)


class UserObjective(objective.Mapping):

    name = objective.Item(objective.Unicode, missing=objective.Ignore)
    email = objective.Item(objective.Unicode, validator=objective.Email())
    password = objective.Item(objective.Unicode)
    since = objective.Item(objective.UtcDateTime, missing=now)


serialized = {
    'email': 'foo@example.com',
    'password': 'foobar'
}


deserialized = UserObjective.deserialize(serialized)


assert deserialized == {
    'password': u'foobar',
    'email': u'foo@example.com',
    'since': datetime.datetime(2001, 9, 11, 0, 0)
}


bad_serialized = {
    'name': 'foobar'
}


try:
    deserialized = UserObjective().deserialize(bad_serialized)

except objective.Invalid as e:

    assert isinstance(e, objective.exc.InvalidChildren)
    assert {(x.node.__name__, x.__class__, x.value) for x in e.children} == {
        ('password', objective.exc.MissingValue, objective.values.Undefined),
        ('email', objective.exc.InvalidValue, 'baz')
    }

Mapping complex structures

import objective


class ProductRequestObjective(objective.BunchMapping):
    @objective.Item()
    class body(objective.Mapping):
        name = objective.Item(objective.Unicode)
        root = objective.Item(objective.Unicode)

        @objective.Item()
        class semantics(objective.List):
            items = objective.Item(objective.Unicode)

    @objective.Item()
    class match(objective.Mapping):
        _id = objective.Item(objective.Field)

Issues, thoughts, ideas

objective is far from complete. There are tons of possible validators I can imagine.

I tried my best (mostly in terms of time) to test.

If you find bugs or you have a great idea, I am totally open to implement it.

Release History

Release History

This version
History Node

0.0.10

History Node

0.0.9

History Node

0.0.8

History Node

0.0.7

History Node

0.0.6

History Node

0.0.5

Download Files

Download Files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
objective-0.0.10.tar.gz (8.6 kB) Copy SHA256 Checksum SHA256 Source Sep 29, 2016

Supported By

WebFaction WebFaction Technical Writing Elastic Elastic Search Pingdom Pingdom Monitoring Dyn Dyn DNS Sentry Sentry Error Logging CloudAMQP CloudAMQP RabbitMQ Heroku Heroku PaaS Kabu Creative Kabu Creative UX & Design Fastly Fastly CDN DigiCert DigiCert EV Certificate Rackspace Rackspace Cloud Servers DreamHost DreamHost Log Hosting