How to convert JSON data into a Python object?

UPDATE

With Python3, you can do it in one line, using SimpleNamespace and object_hook:

import json
from types import SimpleNamespace

data = {name: John Smith, hometown: {name: New York, id: 123}}

# Parse JSON into an object with attributes corresponding to dict keys.
x = json.loads(data, object_hook=lambda d: SimpleNamespace(**d))
print(x.name, x.hometown.name, x.hometown.id)

OLD ANSWER (Python2)

In Python2, you can do it in one line, using namedtuple and object_hook (but its very slow with many nested objects):

import json
from collections import namedtuple

data = {name: John Smith, hometown: {name: New York, id: 123}}

# Parse JSON into an object with attributes corresponding to dict keys.
x = json.loads(data, object_hook=lambda d: namedtuple(X, d.keys())(*d.values()))
print x.name, x.hometown.name, x.hometown.id

or, to reuse this easily:

def _json_object_hook(d): return namedtuple(X, d.keys())(*d.values())
def json2obj(data): return json.loads(data, object_hook=_json_object_hook)

x = json2obj(data)

If you want it to handle keys that arent good attribute names, check out namedtuples rename parameter.

Check out the section titled Specializing JSON object decoding in the json module documentation. You can use that to decode a JSON object into a specific Python type.

Heres an example:

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

import json
def object_decoder(obj):
    if __type__ in obj and obj[__type__] == User:
        return User(obj[name], obj[username])
    return obj

json.loads({__type__: User, name: John Smith, username: jsmith},
           object_hook=object_decoder)

print type(User)  # -> <type type>

Update

If you want to access data in a dictionary via the json module do this:

user = json.loads({__type__: User, name: John Smith, username: jsmith})
print user[name]
print user[username]

Just like a regular dictionary.

How to convert JSON data into a Python object?

You could try this:

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

import json
j = json.loads(your_json)
u = User(**j)

Just create a new object, and pass the parameters as a map.

Note: It does not work for nested classes.

You can have a JSON with objects too:

import json
class Address(object):
    def __init__(self, street, number):
        self.street = street
        self.number = number

    def __str__(self):
        return {0} {1}.format(self.street, self.number)

class User(object):
    def __init__(self, name, address):
        self.name = name
        self.address = Address(**address)

    def __str__(self):
        return {0} ,{1}.format(self.name, self.address)

if __name__ == __main__:
    js = {name:Cristian, address:{street:Sesame,number:122}}
    j = json.loads(js)
    print(j)
    u = User(**j)
    print(u)

How to convert JSON data into a Python object?

How to convert JSON data into a Python object?

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