Build a Chat service using GoLang and WebAssembly (part 4)

ok, for communicating with server we need a Websocket Server - i prefer we develop our WebSocket server-side with nodejs.

our source code => Github Link

What is WebSocket?
Websocket is a simple to use, fast and tested WebSocket client and server implementation.

The Websocket specification defines an API establishing a connection between a web browser and server. WebSocket is used for creating real-time games, chat applications, displaying stock data, etc.

NodeJS and WebSocket
NodeJS is a JavaScript runtime built on Chrome’s V8 JavaScript engine. It is easy to build a WebSocket server implementation with NodeJS.

Traditional HTTP is dependent on client requests, you have to send your request to the server and then get a response from it but in WebSocket, you can send data to the client from the server directly which we call bidirectionally.

Let me introduce you to Websockets:  An event-driven, web-friendly alternative to HTTP. Websockets don't require a client request to fetch data from the server every time.

Building a WebSocket Server With NodeJS
As prerequisites, you should have Nodejs and NPM Installed in your system. If you don’t have it, download and install it from here: https://nodejs.org/en/download/

1) Once you are ready with NodeJs, open a terminal and type the following commands:

mkdir webSocketServer && cd webSocketServer 

2) Create your nodejs project environment:

npm init -y

3) Next, run the following command to install the ws library as a dependency:

npm install ws

4) Create a javascript file for example “webSocketServer.js” and paste the following code for creating a web server:

// Importing the required modules
const WebSocketServer = require('ws');

// Creating a new websocket server
const wss = new WebSocketServer.Server({ port: 8080 })

// Creating connection using websocket
wss.on("connection", ws => {
    console.log("new client connected");
    // sending message
    ws.on("message", data => {
        console.log(`Client has sent us: ${data}`)
    });
    // handling what to do when clients disconnects from server
    ws.on("close", () => {
        console.log("the client has connected");
    });
    // handling client connection error
    ws.onerror = function () {
        console.log("Some Error occurred")
    }
});
console.log("The WebSocket server is running on port 8080");

This code will create a basic WebSocket Server for you and you can provide any port you want while creating the WebSocket server.

5) For testing it, open up a terminal and type:

node webSocketServer.js

Reference:
1) piesocket.com

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In part 5 we are going to write our WebSocket client-side service with Golang WebAssembly and connect to WebSocket nodejs server-side😉