Parse JSON and store data in Python Class

Question

This is my JSON data

[
    {
        "id":1,
        "name":"abc",
        "phone": "12345",
        "Charecteristics": [
            {
                "id":1,
                "name":"Good Looking",
                "rating": "Average",
            }
            {
                "id":2,
                "name":"Smart",
                "rating": "Excellent",
            }
        ]
    },
    { ... },
    { ... }
]

I have two Classes in Python

class Character(object):
    id = 0
    name = ""
    rating = ""

class Person(object):
    id = 0
    name = ""
    phone = ""
    Characteristics = []

I need to parse the JSON data and instantiate appropriate Classes. The Classes are self-explanatory: i.e. Person has an array of Character classes.

How do I instantiate these and store data appropriately?

Also, how will I access particular Person data? i.e. Person's details and characteristics

Note that your JSON example is rather malformed. Apart from the odd quotes you've used, you cannot have multiple Character keys in the Charecteristics object either. — Martijn Pieters
– Martijn Pieters, Commented Sep 11, 2012 at 13:20
I've cleaned up your JSON to actually be valid; note that I've turned both the group of persons and group of characteristics into lists (as they would normally be). — Martijn Pieters
– Martijn Pieters, Commented Sep 11, 2012 at 13:32
@Tichodroma: I'll surely do more research the next time.. Sorry I didnt find the similar question at my first few tries. — Kartik Rokde
– Kartik Rokde, Commented Sep 11, 2012 at 17:10

Jolley71717 · Accepted Answer · 2017-12-10 12:26:50Z

13

Take a look at colander; it makes turning a JSON data structure into Python objects dead easy.

You define a schema:

import colander


class Characteristic(colander.MappingSchema):
    id = colander.SchemaNode(colander.Int(),
                             validator=colander.Range(0, 9999))
    name = colander.SchemaNode(colander.String())
    rating = colander.SchemaNode(colander.String())        


class Characteristics(colander.SequenceSchema):
    characteristic = Characteristic()


class Person(colander.MappingSchema):
    id = colander.SchemaNode(colander.Int(),
                             validator=colander.Range(0, 9999))
    name = colander.SchemaNode(colander.String())
    phone = colander.SchemaNode(colander.String())
    characteristics = Characteristics()


class Data(colander.SequenceSchema):
    person = Person()

then pass in your JSON data structure using the following:

deserialized = Data.deserialize(json.loads(json_string))

edited Dec 10, 2017 at 12:26

Jolley71717

7281 gold badge9 silver badges25 bronze badges

answered Sep 11, 2012 at 13:24

Martijn Pieters

1.1m326 gold badges4.2k silver badges3.4k bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Kartik Rokde Over a year ago

Thanks.. :-) I'm new to Python but have to work with web services,, so using dJango.. Pls consider me amateur.. One more question..

Vanuan Over a year ago

Thats not dead easy. Dead easy would be if it generated python classes given a particular JSON string.

Jonathan Over a year ago

@Vanuan anything that does that?

Vanuan Over a year ago

@Jonathan The closest is this github.com/cwacek/python-jsonschema-objects But it still requires specifying types for each field.

lovasoa · Accepted Answer · 2020-02-22 20:49:04Z

6

If you are writing in python 3.6+, the easiest is probably to use marshmallow-dataclass :

from marshmallow_dataclass import dataclass
from typing import List

@dataclass
class Character:
    id : int
    name : str
    rating : str

@dataclass
class Person:
    id : int
    name : str
    phone : str
    characteristics : List[Character]

my_person = Person.Schema().loads(json_str)

edited Feb 22, 2020 at 20:49

answered Feb 24, 2019 at 13:24

lovasoa

6,9261 gold badge44 silver badges48 bronze badges

Collectives™ on Stack Overflow

Parse JSON and store data in Python Class

2 Answers 2

4 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related