public/subjects/devops/object_to_json/README.md

object_to_json

A lot of information on the web are shared in the JSON format. This exercise will be about transforming object to JSON and vice-versa.

Instructions

You just landed a new job, congrats! Your new task is to build two functions to allow new users to register to your new shiny website.

The new registration information comes as string formatted as JSON. You need to create a file object_to_json.py that will have the following functions inside:

1. create_new_user that will receive a dict and will return a new object of the class User provided below. To be valid, the input dict must have a username key and an email key. The new User will have the same username and email of the input dict. If the input dict is invalid, the default user will be returned.

class User:
    username = 'user'
    email = 'something@email.com'

2. user_to_json that will receive a User and will return the object as a string in JSON format. Be aware of the Python types that can be converted to JSON!

Usage

Here is a possible test.py to test your functions:

from object_to_json import create_new_user, user_to_json

registration_0 = '{"username": "mario", "email": "mario@me.it"}'
registration_1 = '{"city": "Rome", "country": "Italy"}'

user_0 = create_new_user(registration_0)
user_1 = create_new_user(registration_1)

print(user_to_json(user_0))
print(user_to_json(user_1))

$ python3 test.py
{"username": "mario", "email": "mario@me.it"}
{}
$

Hints

• In python, it is possible to define a class and create a class object with the following syntax:

class MyCalss:                      # define a new class
    attribute1 = 0
    attribute2 = 'something else'

my_obj = MyClass()                  # create an object of MyClass

• It is possible to convert an object to dict using the __dict__ casting.

class C:
    a = 1
    b = 2

my_obj = C()
my_obj_dict = my_obj.__dict__ # my_obj_dict will be a dictionary with the object my_obj values

References

• Class and Object
• json.loads()
• json.dumps()