What is JavaScript Backend Example?

In this article, we will learn JavaScript Backend Example,This free Javascript tutorial for complete beginners will help you learn Javascript from scratch.

JavaScript Backend Example

Getting started with JavaScript for the backend

Popular JavaScript backend frameworks

Here’s a simple example of a JavaScript backend application using Node.js and Express.js to create a basic API. This code sets up a basic Express.js server with a single endpoint (/users) that responds with a JSON array of user data when accessed via a GET request.

Javascript

const express = require('express'); 
    const app = express(); 
  
    let users = [ 
    { id: 1, name: 'John Doe', email: 'john@example.com' }, 
    { id: 2, name: 'Jane Smith', email: 'jane@example.com' } 
    ]; 
  
    // Get all users 
    app.get('/users', (req, res) => { 
    res.json(users); 
    }); 
  
    const port = process.env.PORT || 3000; 
    app.listen(port, () => { 
    console.log(`Server is running on port ${port}`); 
    }); 

Explanation

Import Express: We import the Express.js framework to create our server and define routes.
Create Express App: We create an instance of the Express application by calling express(), which returns an Express application object stored in the app variable.
Define Dummy User Data: We define a dummy array called users containing some sample user data. This data will be returned when the /users endpoint is accessed.
Define Route to Get All Users: We use the app.get() method to define a route for handling GET requests to the /users endpoint. When a GET request is made to this endpoint, the callback function (req, res) is executed. In this function, we simply send the users array as a JSON response using res.json(users).
Start the Server: We specify a port for the server to listen on (defaulting to 3000 if no PORT environment variable is set) and call the app.listen() method to start the server. We also log a message to the console indicating that the server is running and on which port.

JavaScript for Backend Development

JavaScript is primarily known as a client-side scripting language, but with the advent of Node.js, it has also become popular for backend development.

Here are some basics of JavaScript backend development: