Skip to main content

A JSON data binding library for Python

Project description

Introduction

This library supports two-way data binding between JSON and Python class.

Turorial

Here is a simple example to use jsonalize:

from jsonalize import *


# Define a class
class MyData(JSONObject):
    def __init__(self):
        JSONObject.__init__(self)
        self.id = JSONString()
        self.name = JSONString()
        self.age = JSONInt()
        self.weight = JSONFloat()


# Create an object of MyData
my = MyData()
my.id = "20190101"
my.name = "Stanley"
my.age = 28
my.weight = 60

# jsonalize the object
json_str = my.to_json()
print(json_str)

# restore the object from json
my2 = JSONObject.from_json(MyData, json_str)
print(my2.to_json())

This example should output the following message:

{"age": 28, "id": "20190101", "weight": 60.0, "name": "Stanley"}
{"age": 28, "id": "20190101", "weight": 60.0, "name": "Stanley"}

Key points from this tutorial

  • A serializable class should inherit the JSONObject class
  • Don't forget to invoke the __init__ method in your class
  • The serializable class attributes should be set as JSON** types

List of supported JSON types

  • JSONInt
  • JSONLong
  • JSONFloat
  • JSONComplex
  • JSONBool
  • JSONString
  • JSONList
  • JSONSet
  • JSONDict
  • JSONObject

Most of the types can be initialized with an initial value, for example:

a_string = JSONString("hello jsonalize")

Remarks for JSONBool

You can't test the value of a JSONBool object with the is keyword, because is will compare the instance id of two objects, but an object of JSONBool is never an instance of True or False.

You can do the test as follows:

a_bool = JSONBool(True)
print(a_bool is True, a_bool == True)
# False, True
print(a_bool.true(), a_bool.true() is True, a_bool.equals(True))
# True, True, True

A more complex example

You can have an object of JSONObject in another JSONObject class:

class Monitor(JSONObject):
    def __init__(self):
        JSONObject.__init__(self)
        self.size = JSONFloat()
        self.power = JSONFloat()
        self.color = JSONString()


class Computer(JSONObject):
    def __init__(self):
        JSONObject.__init__(self)
        self.brand = JSONString()
        self.monitor = Monitor()


computer = Computer()
computer.brand = "Lenovo"
computer.monitor.size = 23.0
computer.monitor.power = 25.0

json_str = computer.to_json()
print(json_str)
#{"brand": "Lenovo", "monitor": {"color": "", "power": 25.0, "size": 23.0}}

computer2 = JSONObject.from_json(Computer, json_str)
print(computer2.to_json())
#{"brand": "Lenovo", "monitor": {"color": "", "power": 25.0, "size": 23.0}}

A list of JSONObject objects?

Look at the following example:

class Student(JSONObject):
    def __init__(self):
        JSONObject.__init__(self)
        self.id = JSONString()
        self.name = JSONString()


class School(JSONObject):
    def __init__(self):
        JSONObject.__init__(self)
        self.address = JSONString()
        self.students = JSONList()


stu1 = Student()
stu1.id = "20190202"
stu1.name = "Stanley"

stu2 = Student()
stu2.id = "20190203"
stu2.name = "Cyrus"

school = School()
school.address = "Central Street No.23"
school.students.append(stu1)
school.students.append(stu2)

json_str = school.to_json()
print(json_str)
#{"students": [{"id": "20190202", "name": "Stanley"}, {"id": "20190203", "name": "Cyrus"}], "address": "Central Street No.23"}

school2 = JSONObject.from_json(School, json_str)
print(type(school2.students[0]), school2.students[0])
#(<type 'dict'>, {u'id': u'20190202', u'name': u'Stanley'})

As you can see here, the deserializing of the School object is incorrect. Because any type of object could be appended to school.students, so jsonalize don't know what to restore when deserializing.

This problem is currently not resolved, maybe I can add a type mapping structure in the future.

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

jsonalize-0.0.2.tar.gz (4.7 kB view hashes)

Uploaded Source

Built Distribution

jsonalize-0.0.2-py2-none-any.whl (6.2 kB view hashes)

Uploaded Python 2

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page