JSON in Python

Introduction to JSON in Python

It is a format for storing data. JSON is referred to as JavaScript Object Notation. It is a lightweight data frame as compared to XML or HTML format. It is simple to understand and looks the same as dictionaries in Python with some minor differences like (Boolean notation and Null notation). Nowadays, JSON is a common data format for storing data/ Fetching data from APIs and configuration files. The JSON format is language independent and is adaptable in python as well. In the case of Python, it has a separate library called JavaScript Object Notation.

How JSON Works in Python?

As we know, Jason is basically a file format to store the data; now, we can use an existing JSON file or create a new python dataset and assign it in JSON format. The Syntax for each operation is discussed below.

1. Importing JSON Library in Python

Python uses the JavaScript Object Notation library. To Install the library, the syntax is given below.

Syntax:

Pip install jsonlib ;
pip install demjson

Once you have a library in python, write the following command for importing it into code.

Import json;

2. Get or Load JSON Format Dataset

To load JSON format data, the following syntax is used as given below.

Syntax:

My_json = json.load( Mason )

In parenthesis, write the name of the file you want to load.

3. Perform Operations on It

Json format is like dictionaries of python with some minor differences. We can perform several operations that we can perform on python dictionaries like viewing datasets, using loops, changing values, aggregating different keys to create a new key, etc.

4. Return JSON Format from Python

When we load the JSON file into python, it is converted to python readable format and is being worked upon. Once the file is ready, it is again converted to the original Json format.

To do this, we use the following Syntax as given below:

Syntax:

My_json_output = json.dump( Mjson )

In parenthesis, write the name of the file you would like to dump.

How to Convert JSON to Python and Python to JSON?

This is the most important part of this article. To convert a JSON document into python, we perform Deserialization or Decoding. To convert a python document into json string, we perform Serialization or Encoding. To perform these  two operations, we need a library called demjson.

Basically, Serialization and Deserialization provides a translator that encodes and decodes the format in return. The below table shows the relation between python and json.

Here we can see some differences that we can identify clearly: numbers in json are treated as int and float and null in json is treated as None in Python, an object in json are dictionaries in python and so on. We will see the conversion in detail in the example section.

Examples to Implement JSON in Python

Here are the examples of implementing JavaScript Object Notation in python as follows:

1. Encoding / Serialization to JSON File

The task is to create one normal python dictionary and then encode the same into a json file. Here we will take None and false type from python, and we will observe how the same has been changed in a json file.

Code:

Import json
#Creating a Dictionary Dataset in python
Mjson= { 'City' : ['Hyd' , 'Delhi' , 'Bombay' , 'Indore', None],
'Food' :['Biryani', 'Momos' , 'Vadapav' , 'Poha' , False]}
# Encoding to json file.
with open("Mjson.json", "w") as write_file:
json.dump(Mjson, write_file)

After executing this code check in the directory of python code, the Mjson.json file would have been created.

Output:

{“City”: [“Hyd”, “Delhi”, “Bombay”, “Indore”, null], “Food”: [“Biryani”, “Momos”, “Vadapav”, “Poha”, false]}

Observe None is changed to null, and False is changed to false.

2. Decoding / Deserialization to Python

The Mjson file which we just now have created now we will decode the same to python again. We will observe the previous observation once again.

Code:

import json;
# Decoding json into python
Import json
with open("Mjson.json", "r") as read_file:
My_python = json.load(read_file)
My_python

The output of the above will be our python dictionary. Observe again the null is converted to None.

Output:

{‘City’: [‘Hyd’, ‘Delhi’, ‘Bombay’, ‘Indore’, None], ‘Food’: [‘Biryani’, ‘Momos’, ‘Vadapav’, ‘Poha’, False]}

3. Formatting of JSON String Using Python Encoder

While encoding json, we can use some specified format defined so as to maintain clarity & format of data. Here we will use separators, indent and sort keys. As we already have a json file with us, we will modify the existing one.

Code:

with open("Mjson.json", "w") as write_file:
json.dump(Mjson, write_file, indent= 4, sort_keys =True, separators = (" | " , " = " ) )

Output:
{
“City” = [
“Hyd” |
“Delhi” |
“Bombay” |
“Indore” |
null
] |
“Food” = [
“Biryani” |
“Momos” |
“Vadapav” |
“Poha” |
false
] }

It’s purely the choice of coder how json format is required.

Advantages

Let see some of the advantages of Python JavaScript Object Notation in detail given below:

• JSON is a formation to transfer data from server to client and vice versa. HTML and XML provide static data, while most of the data we need is dynamic; in this case, JSON can help.
• When an Asynchronous request is sent to a server via browser or application, the server receives the request and returns data (what format any format is fine, the client needs data only). Now, if the format is Html format, it will give design as well as data, but the client already has designed; it needs only data.
• In the server, the data will be in the form of objects with properties, so it makes data as complex data type objects. Now for this, we have JSON (JavaScript Object Notation).JavaScript Object Notation makes it easy to process complex data with multiple classes and objects.
• It is of utmost need to use json type in DS and ML research; python provides solutions for the same. Server Serialise the objects, and the client de-serialize the object and read it.

Conclusion

Json is a format and is generally produced from different java-scripts and APIs which are on JS. With the help of python, one can communicate with json files. In python, Deserialization or decoding is used to convert a json object into a python dictionary, and Serialization or encoding is used for converting python doc into a json object. This article covers both and also which format the programmer wants can choose it.

Recommended Articles

This is a guide to the JSON in Python. Here we discuss how JSON works in Python along with various examples and its advantages in detail. You may also look at the following articles to learn more-

1. JSON object
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3. JSON vs AJAX
4. JSON in Java