Working With JSON Data in Python

How to parse Nested Json Data in Python? How to read and write Json Data in File

If you are working with Json, include the json module in your code.

 import json 

Convert Python Objects to Json string in Python. And then from Json string to Json Dictionary.

import json

# a Python object (dict):
x = {
  "name": "John",
  "age": 30,
  "city": "New York"
}

# convert into JSON string:
y = json.dumps(x)
# convert json string to Json Dict
jsonDict = json.loads(y)

Now to access any Json key.

import json

x = {
  "name": "John",
  "age": 30,
  "city": "New York"
}
# convert into JSON string:
y = json.dumps(x)
# convert json string to Json Dict
jsonDict = json.loads(y)

print (jsonDict['name'])
print (jsonDict['age'])

Write the json data in the file

import json

data = {
'bill': 'tech',
'federer': 'tennis',
'ronaldo': 'football',
'people' : [ {
'name': 'Scott',
'website': 'stackabuse.com',
'from': 'Nebraska'}, 
{'name': 'Larry',
'website': 'google.com',
'from': 'Michigan' } ]
}

with open('data.txt', 'w') as outfile:
    json.dump(data, outfile)

Read the data from Json file (We will read the same data file in which we dump the data above)

import json

with open('data.txt') as json_file:
    data = json.load(json_file)
    print ("bill:", data['bill'])
    print ("")
    for person in data['people']:
        print("Name:", person['name'])
        print("Website:", person['website'])
        print("From:", person['from'])
        print("")

Iterate through Json data which has list, json string, nested Json. Here I will explain how to work with complex Json and extract data from it

import json

def checkList(ele, prefix):
    for i in range(len(ele)):
        if (isinstance(ele[i], list)):
            checkList(ele[i], prefix+"["+str(i)+"]")
        elif (isinstance(ele[i], str)):
            printField(ele[i], prefix+"["+str(i)+"]")
        else:
            checkDict(ele[i], prefix+"["+str(i)+"]")

def checkDict(jsonObject, prefix):
    for ele in jsonObject:
        if (isinstance(jsonObject[ele], dict)):
            checkDict(jsonObject[ele], prefix+"."+ele)

        elif (isinstance(jsonObject[ele], list)):
            checkList(jsonObject[ele], prefix+"."+ele)

        elif (isinstance(jsonObject[ele], str)):
            printField(jsonObject[ele],  prefix+"."+ele)

def printField(ele, prefix):
    print (prefix, ":" , ele)


data = {'field1': 'hello1',
        'field2': 'hello2',
        'NestedJson': {'Field': 'helloNested1',
                       'List': [{'f01': 'v01', 'f02': 'v02'},
                                          {'f11': 'v11'}],
                       'NestedNestedJson': {'Field1': 'value1',
                                            'Field2': 'value2'}
                        },
        'List': [{'a1': 'b1'},
                 {'a1': 'b1'}],
        'ElementList': ['ele1', 'ele2', 'ele3']
        }

#Iterating all the fields of the JSON
for element in data:
  #If Json Field value is a Nested Json
    if (isinstance(data[element], dict)):
        checkDict(data[element], element)
    #If Json Field value is a list
    elif (isinstance(data[element], list)):
        checkList(data[element], element)
    #If Json Field value is a string
    elif (isinstance(data[element], str)):
        printField(data[element], element)

The Output of above code is:-

field1 : hello1
field2 : hello2
NestedJson.Field : helloNested1
NestedJson.List[0].f01 : v01
NestedJson.List[0].f02 : v02
NestedJson.List[1].f11 : v11
NestedJson.NestedNestedJson.Field1 : value1
NestedJson.NestedNestedJson.Field2 : value2
List[0].a1 : b1
List[1].a1 : b1
ElementList[0] : ele1
ElementList[1] : ele2
ElementList[2] : ele3