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In today’s interconnected digital world, building robust web applications often involves integrating data from various sources. PHP Rest API (Representational State Transfer Application Programming Interface) has emerged as a powerful solution for facilitating data communication between different systems. In this blog post, we’ll explore the world of PHP Rest API, its benefits, and how it simplifies the development of dynamic and data-driven web applications.

What is PHP REST API?

A PHP REST API is a web service built using PHP that follows REST (Representational State Transfer) architecture principles. It allows applications to communicate over HTTP using standard methods like:

• GET
• POST
• PUT
• DELETE

Instead of returning HTML pages, a REST API typically returns data in:

• JSON (most common)
• XML (legacy systems)

This makes it ideal for:

• Mobile applications
• Single Page Applications (SPA)
• Third-party integrations
• Microservices architecture

What is REST?

REST stands for Representational State Transfer.

It is an architectural style that defines constraints for building scalable and stateless web services.

Core REST Principles

1. Stateless – Each request must contain all required information.
2. Client-Server Architecture
3. Uniform Interface
4. Resource-Based URLs
5. Standard HTTP Methods

Example Resource URL:

/api/orders/222

Here, orders is the resource and 222 is its identifier.

What is an API?

API stands for Application Programming Interface.

It is a bridge that allows two software systems to communicate.

For example:

• A mobile app fetching order data from a server.
• A frontend React app calling a backend PHP API.
• A payment gateway validating transaction data.

When REST principles are applied to an API, it becomes a REST API.

How REST API Works (CRUD + HTTP Methods)

REST requests are related to CRUD operations (Create, Read, Update, Delete) in the database, REST uses GET, POST, PUT and DELETE requests. Here below you can see what are the functions.

• GET – it is used to transfer data from client to server in HTTP protocol using URL String
• POST – it is also used to transfer data from client to server in HTTP protocol but it carries request parameters in the message body which makes it a more secure way
• PUT – This method request is used to enclosed the entity under the supplied Request URL.
• Options – It shows which technique is supportable.
• HEAD – It returns the meta-information.

REST maps HTTP methods to database CRUD operations:

Example:

GET /api/orders/222
POST /api/orders
PUT /api/orders/222
DELETE /api/orders/222

Rest API Example

Let’s learn about REST API in PHP with the following example. Follow the below steps to create a simple REST API program in PHP using XAMPP on a local computer:

1). Create a database called “rest_api_php” from PHPMyAdmin

2). Once the database is created, run the following SQL command to create a table:

CREATE TABLE IF NOT EXISTS `order_transactions` (
`id` int(30) NOT NULL AUTO_INCREMENT,
`order_id` int(80) NOT NULL,
`amount` decimal(10,2) NOT NULL,
`response_code` int(10) NOT NULL,
`response_desc` varchar(80) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `order_id` (`order_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 ;

Once the table is created with the above command, add some dummy data.

3).  Now, create a file called “database.php” inside the “inc” directory of your project root directory for setup database connection. Add the following code to the “database.php” file:

$conn = mysqli_connect("localhost","root","","allphptricks");
if (mysqli_connect_errno()){
echo "Failed to connect to MySQL: " . mysqli_connect_error();
die();
}

4). Now create an “index.php” file in the root directory of your project and add the following code

<?php
header("Content-Type:application/json");
if (isset($_GET['order_id']) && $_GET['order_id']!="")
{
    include('inc/database.php');
    $order_id = $_GET['order_id'];
    $result = mysqli_query(
    $conn,
    "SELECT * FROM `order_transactions` WHERE order_id=$order_id");
    if(mysqli_num_rows($result)>0){
    $row = mysqli_fetch_array($result);
    $amount = $row['amount'];
    $response_code = $row['response_code'];
    $response_desc = $row['response_desc'];
    response($order_id, $amount, $response_code,$response_desc);
    mysqli_close($conn);
    }
    else
    {
    response(NULL, NULL, 200,"No Record Found");
    }
}
else
{
    response(NULL, NULL, 400,"Invalid Request");
}

function response($order_id,$amount,$response_code,$response_desc){
    $response['order_id'] = $order_id;
    $response['amount'] = $amount;
    $response['response_code'] = $response_code;
    $response['response_desc'] = $response_desc;
    $json_response = json_encode($response);
    echo $json_response;
}

5). Your application is completed. Now, you will get order transaction-related data by running the following URL  where “rest-api”  is the name of the project root directory.

http://localhost/rest-api/?order_id=222

You will get output like following:

Security Best Practices for PHP REST API

When building production-level REST API in PHP, follow these:

1. Use Prepared Statements

Prevents SQL injection.

2. Validate Input

Always sanitize and validate user input.

3. Use Authentication

• JWT (JSON Web Token)
• OAuth 2.0
• API Keys

4. Enable HTTPS

Never expose APIs over HTTP in production.

5. Implement Rate Limiting

Prevent brute-force and DDoS.

6. Use Proper HTTP Status Codes

• 200 – Success
• 201 – Created
• 400 – Bad Request
• 401 – Unauthorized
• 404 – Not Found
• 500 – Server Error

Benefits of PHP REST API

1. Simplified Communication

JSON-based data exchange is lightweight and fast.

2. Platform Independence

Works with:

• React
• Angular
• Vue
• Mobile Apps
• IoT Devices

3. Scalability

Stateless design supports microservices architecture.

4. Reusability

Same API can power:

• Website
• Android App
• iOS App
• Admin Dashboard

5. Easy Integration

Third-party systems can consume your API easily.

Real-World Use Cases

• E-commerce Order API
• Payment Gateway Integration
• User Authentication System
• Booking System
• SaaS Backend APIs
• Headless CMS

Advanced PHP REST API Architecture (Recommended for 2026)

Instead of writing raw PHP files, modern developers use:

• MVC Structure
• Composer
• Routing Libraries
• Environment Variables (.env)
• API Versioning

Example:

/api/v1/orders
/api/v2/orders

Recommended PHP Frameworks for REST API

For large applications, use:

• Laravel – Most popular PHP framework
• Slim Framework – Lightweight API framework
• Symfony – Enterprise-level
• CodeIgniter 4 – Fast and simple

Frameworks provide:

• Routing
• Middleware
• Authentication
• Validation
• ORM
• Testing tools

Conclusion

The PHP REST API remains one of the most powerful ways to build scalable and interoperable web applications.

By following REST principles and modern PHP best practices like:

• Using PDO
• Prepared statements
• Proper HTTP status codes
• JSON responses
• Security enhancements

You can build secure, scalable, and production-ready APIs.

Whether you’re building:

• A simple order lookup system
• A SaaS backend
• A mobile app backend
• A headless eCommerce platform

Mastering REST API in PHP will significantly enhance your backend development skills in 2026 and beyond.