← Back to Chapters

REST API Principles

? REST API Principles

? Quick Overview

REST (Representational State Transfer) is an architectural style for designing networked applications. REST APIs allow clients and servers to communicate using standard HTTP methods in a simple, scalable, and stateless manner.

? Key Concepts

  • Resources – Data objects exposed by the API
  • URIs – Unique identifiers for resources
  • Stateless Operations – Each request is independent
  • HTTP Methods – GET, POST, PUT, DELETE
  • Representation – JSON or XML formats

? Syntax / Theory

In REST, everything is treated as a resource. Each resource is accessed using a unique URI and manipulated using standard HTTP verbs. The server does not store any client context between requests.

? Code Example(s)

? View Code Example
// Example RESTful endpoint definitions
GET /api/users
POST /api/users
GET /api/users/1
PUT /api/users/1
DELETE /api/users/1

? Live Output / Explanation

Request → Response Flow

A client sends an HTTP request to a specific URI. The server processes the request and returns a response with a status code and data (usually JSON).

? Interactive Example / Diagram

Click the buttons below to simulate REST requests.

// Console waiting for requests...
? View Source Code for Logic
// Simple fetch request demonstrating stateless communication
fetch("/api/users")
.then(response => response.json())
.then(data => console.log(data));

? Use Cases

  • Web and mobile application backends
  • Microservices communication
  • Public APIs (payment, maps, social media)
  • Integration between systems

? Tips & Best Practices

  • Use nouns for resource names
  • Follow proper HTTP status codes
  • Keep APIs stateless
  • Version your APIs

? Try It Yourself

  • Create a REST API for managing products
  • Test endpoints using Postman
  • Implement GET and POST operations
  • Return proper HTTP status codes