How to Build or Create a Chat Application using Node.js and Socket.Io?


Node.js is not the remedy for everything, though, it can absolutely perform better with Websockets easier when using with the Socket.io library. Using WebSockets you can easily create real-time applications and also multiplayer games. This article will show you how to easily build a chat app using Node.js and Socket.io simple yet significantly.

To build a real-time chat application, you have to think about implementing a real-time system which should be eligible for sending and receiving data. It will not be done just by a relational database and Ajax Calls. So here to make that possible and easy WebSocket and library socket.io is very essential to get your job done.

Let’s understand that basic technical stack of WebSockets and Sockets.io. WebSockets comes with many benefits and it can be used in different projects.

Learn why you should and how to use this advanced technology to build chat application development.

Want to create create chat application using node js?

» Know what is WebSocket Protocol, Node.js and Socket.io?

WebSocket is actually an internet communication protocol with a compatible and interesting feature: it offers a full-duplex channel over a single TCP (Transmission Control Protocol) connection.

Using WebSockets, a client and a server will with each other in real time, just like they were connected via telephone call. Once both are connected, a client will be able to receive data from the server, without refreshing the web page continuously. On the other hand, the server will also be able to receive data from the client inside in real time with the same connection.

» The Benefit of the WebSocket:

They are capable to work with an event-driven model: both the client and server can respond to events and messages. In recent times, WebSockets created a lot of good opportunities for web developers.

If you are wondering how to implement this excellent technology into Node.Js application, then the answer is Socket.io. It is most popular real-time engines for Node.Js.

What is Socket.io used For?

Socket.IO is used by many companies and developers today. Its notable users include Microsoft Office, Yammer, and Zendesk. It is used in building instant messaging applications, real-time analytics, monitoring and for streaming and document collaboration.

The experts say that “Socket.IO certainly uses WebSocket as a transport when possible [..] but a WebSocket client will not be able to connect to a Socket.IO server, and vice versa a Socket.IO client will not be able to connect to a WebSocket server”.

How Does Socket.IO Really Work In Building An App?

Socket.io has two parts – one is server part (for Node.JS) and second is clients part (for web browsers). They have similar APIs based on event-driven architecture. Socket.IO allows using extra features such as sending data to a large number of sockets at the same time (broadcasting) or storing the data.

The simplest way to describe how Socket.IO works is to explain it with the example. By composing just 22 lines of JavaScript code, developers can build a simple WebSockets-based chat. Below you will find both the server and the client part with comments.

» Node.Js:

Node.js is a Javascript back-end technology administered by the server as PHP, Ruby or Python. JavaScript uses events. Node.js holds this particularity so it becomes easy to make asynchronous code. Node.js has package manager: npm. It is easy to install, update, delete packages. Apart from that, there is a bunch of Nodejs benefits for enterprise web app development.

The Chat App: Understand Architecture of the Application

On the first point, you have to separate two parts in the chat application: the client part and the server part. you will have to build the two parts to make application up and running.

The server will be managed by node.js to make the launch the packages and the website. This code will invisible by the client. The client part will be loaded on the computer of the client. It will have direct access to the files (html/css and js).

» Server-side:

Socket.IO works by including event listeners to an instance of http.Server. To add Socket.IO support to a http.Server. You have to build the file app.js that will launch server and all the packages. Now you require to configure socket.io to be ready to jump into the WebSocket world.

io object will give you an access to the socket.io library. io object is now monitoring to each connection to the app. Each time when a new user is joining, it will print out “New user connected” in the console.

» Client-side:

The HTTP server will start to serve the client library at /socket.io/socket.io.js. To connect to Socket.IO server.

» Sending and Receiving Data:

Since both the server and client’s Socket object perform as EventEmitters, you can transmit and listen for events in a bi-directional way. Socket.IO has played an essential role in the popular adoption of Node.js by making WebSockets convenient and secure.

New Version expresses a significant step in its development and the extraction of Engine.IO has initiated some interesting possibilities for the Node.js ecosystem.


WebSockets is one of the most impressive support that was brought into the use with HTML5. It answers to a lot of queries that web application developers have struggled with before. WebSockets in joining with external libraries such as Socket.IO opens many possibilities. This definitely is a remarkable technology.

With above you learnt how to build a chat based app using Node.js and Socket.io. Without both node.js and Socket.io, building a chat based app is a difficult task. Therefore, if you are looking to build a chat based app then you must hire Node.js developers to fulfill your project requirement.

Let’s build your own app

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