Decoding json message inside of string

Question

I have the following decoding function;

def flatten_data(json_data):
    """
    Arguments:
        json_data (dict): json data
    Returns:
        dict : {a:1, b:2, b_c:1, b_d:2}
    """
    out = {}

    def flatten(x, name=''):
        if type(x) is dict:
            for a in x:
                flatten(x[a], name + a + '_')
        elif type(x) is list:
            out[name[:-1]] = x
        else:
            out[name[:-1]] = x

    flatten(json_data)
    return out

If I am giving the following JSON body input to this function;

{
  "id": "123",  
  "name": "Jack",  
  "createdAt": 20221212,  
  "region": '{"country": "USA", "city": "NewYork"}'
}

I need to get the output as follows;

{
  "id": "123",  
  "name": "Jack",  
  "createdAt": 20221212,  
  "region_country": "USA",
  "region_city": 'NewYork'
}

How can I modify my flatten_data function?

Answer 1

You can do it this way with some modification to your existing code where the value is str because in this case, the region \has quotation "". So to handle this you can use built-in json module.

import json

def flatten_data(json_data):
    """
    Arguments:
        json_data (dict): json data
    Returns:
        dict : {a:1, b:2, b_c:1, b_d:2}
    """
    out = {}

    def flatten(x, name=''):
        if type(x) is dict:
            for a in x:
                flatten(x[a], name + a + '_')
        elif type(x) is list:
            out[name[:-1]] = x
        elif type(x) is str:
            try:
                y = json.loads(x)
                flatten(y, name)
            except:
                out[name[:-1]] = x
        else:
            out[name[:-1]] = x

    flatten(json_data)
    return out

json_data = {
  "id": "123",  
  "name": "Jack",  
  "createdAt": 20221212,  
  "region": '{"country": "USA", "city": "NewYork"}'
}

print(flatten_data(json_data))

Output:

{
  "id": "123",  
  "name": "Jack",  
  "createdAt": 20221212,  
  "region_country": "USA",
  "region_city": 'NewYork'
}