Create a JSON Response in Python – Linux Hint

Added 2 months ago
Summary: The JSON (JavaScript Object Notation) file is a very popular medium to interchange data between different formats. Its main purpose is to transfer data between the server and the client. This guide will help you learn how response.json() function can be used to parse JSON response using Python request library.
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JSON (JavaScript Object Notation) file is a very popular medium to interchange data between different formats. It contains data in text format that is supported by various languages such as Python, PHP, PERL, etc. The main purpose of the JSON file is to transfer data between the server and the client. The requests are generated by Python to retrieve the data from a particular resource URI. If the response of the request is returned in JSON format then the content of the response can be retrieved using the response.json() function. It returns the response by using a Python dictionary object. How this function can be used to parse JSON response using the Python request library will be shown in this tutorial.

JSON Response:

The request module of Python contains the JSON decoder to work with the JSON data. The response.json() function returns a JSON response if the JSON decoder works properly. The response.json() function raises the exception if the JSON decoder fails and the JSON response does not contain any data or invalid data. The return value of the response.raise_for_status() function or the  response.status_code is required to be checked before executing the response.json() function.

Different uses of response.json():

Three different uses of the response.json() function will be shown in this part of the tutorial.

Example-1: Simple use of response.json()

The simple use of the response.json() function will be expounded in this example. The response for the get request of the URI, https://api.github.com/ is stored in a variable named response. Next, the value of the response variable is checked. If the response variable contains any invalid response, then it will print an error message. If the response variable contains a valid response which is the status code of the response and its content a success message will print.

# Import requests module

import requests

# Create a get request

response = requests.get('https://api.github.com/')

# Check the response

if response:

    # Print the response status code

    print('The status code of the response is %d' %response.status_code)

    # Print the JSON content

    print('The JSON content is: \n%s' %response.json())

    # Print the success message

    print('\nThe request is handled successfully.')

else:

    # Print the error message for the invalid response

    print('Invalid response.')

Output:

The following output will appear after executing the above script.

Example-2: Use of response.json() with exception handling

The way of using the response.json() function with exception handling will be shown in this example. HttpError module is imported with the request module in the script to handle the exception. Here, the URI address will be taken from the user to use the requests.get() function. The response of this request will be stored in the response variable. Next, response.raise_for_status() function is used to check the response of the request whether it is valid or invalid. If the response is invalid, then an exception will be generated and the code of any except block will be executed based on the exception. If the response is valid, then the content of the response variable will be iterated using a for loop to print the values of the dictionary in each line that contains the response data.

# Import requests module

import requests

# Import HTTPError for exception handling

from requests.exceptions import HTTPError

# Define the URI

uri = input('Enter the a valid URI:\n')

# Print waiting message

print('Waiting for the response...\n')

try:

    # Create a get request to read feeds content of github

    response = requests.get(uri)

    # Raise exception if the response was unsuccessful

    response.raise_for_status()

    # Read the JSON content

    jsonResponse = response.json()

    print("The JSON content is: \n")

    # Read and print each key-value pair from the JSON response

    for key, value in jsonResponse.items():

        print(key, ":", value)

# Print error message for the HTTP error

except HTTPError as http_err:

    print('HTTP error occurred: %s' %http_err)

# Print error message for the HTTP error

except Exception as err:

    print('Other error occurred: %s' %err)

Output:

The following output will appear after executing the script when a non-existence URI value will be provided by the user. Here, the HTTPError exception had been generated alongside the corresponding error message.


The following output will appear after executing the script when an invalid URI value will be provided by the user. Here, the other exception had been generated with a  corresponding error message.

The following output will appear after executing the script when a valid URI value will be provided by the user. Here, the JSON content has been printed properly.

Example-3: Use of response.json() with query string

The way of using the response.json() function with query string will be shown in this example. Here, the requests.get() function used a query string value with the URI using params. It will search the entries for the PERL language in the given repositories. If the response variable contains a valid response then the repository name and description will be printed, otherwise, there will be an error message.

# Import requests module

import requests

# Searching in github's repository using query string

response = requests.get(

    'https://api.github.com/search/repositories',

    params={'q': 'requests+language:perl'},

)

# Check the response

if response:

    # Read the JSON content

    json_response = response.json()

    # Read the particular repository item

    repository = json_response['items'][0]

    # Print the repository name

    print('Repository name: %s' %repository["name"])

    # Print the repository description

    print('Repository description: %s' %repository["description"])

else:

    # Print the error message for the invalid response

    print('Invalid response.')

Output:

The following output will appear after executing the above script. The repository name and description for the PERL language had been printed here.

Conclusion:

Different ways to send the request to a particular URI and read the response using the response.json() function was shown in this tutorial using simple examples. I hope this tutorial will help the readers to understand the use of JSON response in Python and apply it properly in their script when it is required.

About the author

Fahmida Yesmin

I am a trainer of web programming courses. I like to write article or tutorial on various IT topics. I have a YouTube channel where many types of tutorials based on Ubuntu, Windows, Word, Excel, WordPress, Magento, Laravel etc. are published: Tutorials4u Help.