json-object-factory

Simplifies building custom encoders and object-hooks for Python's default JSON implementation.

Installation

$ pip install json-object-factory

Usage

Add encoders and decoders to the registry:

import jsonfactory

class MyJsonHandler(object):
    def encode(self, o):
        if isinstance(o, MyCustomClass):
            return o.serialize()
        return None

    def decode(self, d):
        if 'some_custom_key' in d:
            return MyCustomClass(**d)
        return d

jsonfactory.Registry.register(MyJsonHandler)

Or use the included decorators:

@jsonfactory.register
class MyOtherJsonHandler(object):
    ...

@jsonfactory.encoder
def an_encoder_function(o):
    ...

@jsonfactory.decoder
def a_decoder_function(d):
    ...

Then use the module's dumps and loads functions:

json_str = jsonfactory.dumps(obj_dict, indent=2)

new_obj_dict = jsonfactory.loads(json_str)

Notes

• The calling signature for encoder functions follows that of the built-in JSONEncoder with one exception:
  • If no modifications are needed and the object should be passed to the base encoder's handler, None should be returned. This differs from the normal method of calling super(MyEncoder, self).default(o) (that would most likely be an error since subclassing JSONEncoder isn't necessary).
• The signature for decoder functions follows the object_hook signature in the built-in implementation