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python_jsonschema_objects 0.0.12

An object wrapper for JSON Schema definitions

Latest Version: 0.3.2


python-jsonschema-objects provides an *automatic* class-based binding to
JSON schemas for use in python.

For example, given the following schema:

.. code:: schema

"title": "Example Schema",
"type": "object",
"properties": {
"firstName": {
"type": "string"
"lastName": {
"type": "string"
"age": {
"description": "Age in years",
"type": "integer",
"minimum": 0
"dogs": {
"type": "array",
"items": {"type": "string"},
"maxItems": 4
"gender": {
"type": "string",
"enum": ["male", "female"]
"deceased": {
"enum": ["yes", "no", 1, 0, "true", "false"]
"required": ["firstName", "lastName"]

jsonschema-objects can generate a class based binding. Assume here that
the schema above has been loaded in a variable called ``schema``:

.. code:: python

>>> import python_jsonschema_objects as pjs
>>> builder = pjs.ObjectBuilder(schema)
>>> ns = builder.build_classes()
>>> Person = ns.ExampleSchema
>>> james = Person(firstName="James", lastName="Bond")
>>> james.lastName
>>> james
<example_schema lastname="Bond" age="None" firstname="James">

Validations will also be applied as the object is manipulated.

.. code:: python

>>> james.age = -2
python_jsonschema_objects.validators.ValidationError: -4 was less
or equal to than 0

The object can be serialized out to JSON:

.. code:: python

>>> james.serialize()
'{"lastName": "Bond", "age": null, "firstName": "James"}'


Ever struggled with how to define message formats? Been frustrated by
the difficulty of keeping documentation and message definition in
lockstep? Me too.

There are lots of tools designed to help define JSON object formats,
foremost among them `JSON Schema <http:"">`__. JSON
Schema allows you to define JSON object formats, complete with

However, JSON Schema is language agnostic. It validates encoded JSON
directly - using it still requires an object binding in whatever
language we use. Often writing the binding is just as tedious as writing
the schema itself.

This avoids that problem by auto-generating classes, complete with
validation, directly from an input JSON schema. These classes can
seamlessly encode back and forth to JSON valid according to the schema.

Other Features

The ObjectBuilder can be passed a dictionary specifying 'memory' schemas
when instantiated. This will allow it to resolve references where the
referenced schemas are retrieved out of band and provided at

For instance:

.. code:: schema

"title": "Address",
"type": "string"

.. code:: schema

"title": "AddlPropsAllowed",
"type": "object",
"additionalProperties": true

.. code:: schema

"title": "Other",
"type": "object",
"properties": {
"MyAddress": {"$ref": "memory:Address"}
"additionalProperties": false

Generated wrappers can also properly deserialize data representing
'oneOf' relationships, so long as the candidate schemas are unique.

.. code:: schema

"title": "Age",
"type": "integer"

.. code:: schema

"title": "OneOf",
"type": "object",
"properties": {
"MyData": { "oneOf":[
{"$ref": "memory:Address"},
{"$ref": "memory:Age"}
"additionalProperties": false



pip install python_jsonschema_objects


Tests are managed using the excellent Tox. Simply ``pip install tox``,
then ``tox``.


0.0.12 - Support "true" as a value for 'additionalProperties'

0.0.11 - Generated wrappers can now properly deserialize data
representing 'oneOf' relationships, so long as the candidate schemas are

0.0.10 - Fixed incorrect checking of enumerations which previously
enforced that all enumeration values be of the same type.

0.0.9 - Added support for 'memory:' schema URIs, which can be used to
reference externally resolved schemas.

0.0.8 - Fixed bugs that occurred when the same class was read from
different locations in the schema, and thus had a different URI

0.0.7 - Required properties containing the '@' symbol no longer cause
``build_classes()`` to fail.

0.0.6 - All literals now use a standardized LiteralValue type. Array
validation actually coerces element types. ``as_dict`` can translate
objects to dictionaries seamlessly.

0.0.5 - Improved validation for additionalItems (and tests to match).
Provided dictionary-syntax access to object properties and iteration
over properties.

0.0.4 - Fixed some bugs that only showed up under specific schema
layouts, including one which forced remote lookups for schema-local

0.0.3b - Fixed ReStructuredText generation

0.0.3 - Added support for other array validations (minItems, maxItems,

0.0.2 - Array item type validation now works. Specifying 'items', will
now enforce types, both in the tuple and list syntaxes.

0.0.1 - Class generation works, including 'oneOf' and 'allOf'
relationships. All basic validations work.  
File Type Py Version Uploaded on Size
python_jsonschema_objects-0.0.12-py2-none-any.whl (md5) Python Wheel 2.7 2014-07-22 46KB
python_jsonschema_objects-0.0.12.tar.gz (md5) Source 2014-07-22 17KB