AJAX - RESTful API Consumption using AJAX

RESTful API consumption using AJAX refers to the process of communicating with a web server through REST APIs without reloading the web page. Modern web applications use REST APIs to exchange data between the client (browser) and server efficiently.

REST stands for Representational State Transfer. It is an architectural style used for designing networked applications. In REST architecture, resources such as users, products, or posts are accessed using standard HTTP methods.

In AJAX, JavaScript sends asynchronous requests to REST APIs and receives responses in formats like JSON or XML. This allows dynamic updating of web content without refreshing the entire page.

Basic REST HTTP Methods

GET
Used to retrieve data from the server. Example: fetching a list of students from a database.

POST
Used to send new data to the server. Example: submitting a registration form.

PUT
Used to update existing data on the server.

DELETE
Used to remove data from the server.

How AJAX Works with REST APIs

  1. A user performs an action on a webpage such as clicking a button.

  2. JavaScript creates an AJAX request.

  3. The request is sent to a REST API endpoint.

  4. The server processes the request.

  5. The server sends a response, usually in JSON format.

  6. JavaScript updates only the required part of the webpage.

Example using XMLHttpRequest

var xhr = new XMLHttpRequest();
xhr.open("GET", "https://api.example.com/users", true);

xhr.onload = function () {
    if (xhr.status === 200) {
        var data = JSON.parse(xhr.responseText);
        console.log(data);
    }
};

xhr.send();

Example using Fetch API

fetch("https://api.example.com/users")
.then(response => response.json())
.then(data => {
    console.log(data);
});

Advantages of Using REST APIs with AJAX

It enables faster web applications because only required data is loaded.
It separates frontend and backend development.
It allows mobile apps, websites, and other systems to use the same API.
It improves user experience by avoiding full page reloads.

Real-World Uses

Online shopping websites load products dynamically.
Social media platforms update notifications instantly.
Weather and map applications fetch live data from servers.

RESTful API consumption using AJAX is a core concept in modern web development because most applications depend on APIs to exchange data efficiently between client and server.