tojson.py

# -*- coding: utf-8 -*-

import json

from decimal import Decimal


class MyEncoder(json.JSONEncoder):
    def default(self, obj):
        data = {'__class__': obj.__class__.__name__,
                '__module__': obj.__class__.__module__,
                }

        if hasattr(obj, '__dict__'):
            data.update(obj.__dict__)

        if isinstance(obj, Decimal):
            data.update({'Decimal': float(obj)})

        return data


class MyDecoder(json.JSONDecoder):
    def __init__(self):
        json.JSONDecoder.__init__(self, object_hook=self.dict_to_object)

    def dict_to_object(self, d):
        if '__class__' in d:
            inst = None
            class_name = d.pop('__class__')
            module_name = d.pop('__module__')
            module = __import__(module_name)
            class_ = getattr(module, class_name)
            if 'Decimal' in d:
                arg = Decimal(d.pop('Decimal'))
                inst = class_(arg)
            else:
                args = dict((key.encode('ascii'), value)
                            for key, value in d.items())
                inst = class_(**args)
        else:
            inst = d
        return inst


class MyTest(object):
    def __init__(self, name):
        self.name = name


# 测试
mytest = [Decimal(3.3), [1, 2, 3], {'a': 1, 'b': 2},
          MyTest({'a': 1, 'b': 2}), MyTest(Decimal(3.3))]
test_encode = MyEncoder().encode(mytest)
print test_encode

test_decode = MyDecoder().decode(test_encode)
print test_decode