Simple JSON protocol that falls back on pickle

json_pickle.py

import numpy as np
import json
import sys
try:
    import cPickle as pickle
except ImportError:
    import pickle


if sys.version.startswith('3'):
    _str_type = str
else:
    _str_type = unicode


class _MyEncoder(json.JSONEncoder):

    def default(self, obj):
        return pickle.dumps(obj, protocol=-1).decode('latin-1')


class _MyDecoder(json.JSONDecoder):

    def __init__(self):
        json.JSONDecoder.__init__(self, object_hook=self.dict_to_obj)

    def dict_to_obj(self, d):
        return dict_to_obj(d)


def json_pickle_dumps(obj):
    return _MyEncoder().encode(obj)


def json_pickle_loads(str_):
    return _MyDecoder().decode(str_)


def dict_to_obj(d):
    for (key, value) in d.items():
        if isinstance(value, dict):
            d[key] = dict_to_obj(value)
            continue

        if isinstance(value, _str_type):
            try:
                d[key] = pickle.loads(value.encode('latin-1'))
            except Exception:
                pass
    return d


if __name__ == '__main__':
    import time
    test = dict(a=np.ones((4, 4)))
    t0 = time.time()
    d = json_pickle_dumps(test)
    out = json_pickle_loads(d)
    print(time.time() - t0)
    print(out)
    t0 = time.time()
    d2 = pickle.dumps(test, protocol=-1)
    out2 = pickle.loads(d2)
    print(time.time() - t0)
    print(out2)
    print(len(d), len(d2))