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title
| title |
|---|
| WebSockets |
WebSockets
Web Sockets is a technology that allows you to create an interactive connection between a client and a server for exchanging data in real time. WebSockets allow you to work in two streams, which distinguishes this technology from HTTP.
How do WebSockets work?
WebSockets do not need repeated calls to respond. It is enough to make one request and wait for a response. You can listen to the server, which will send the answer on readiness.
When can I use WebSockets?
- Real-Time Applications
- Chat application
- IoT applications
- Multiplayer games
When not to use WebSockets?
WebSockets are already supported in 95% of browsers, but sometimes this technology is not required. For example, if you are creating a simple CMS where real-time functionality is not required.
WebSocket Example
Frontend (No need for an import, WebSockets are supported by [every major browser])
const ws = new WebSocket('ws://localhost:3000');
ws.onmessage = function(e){
console.log('Message received from WebSocket');
const parsedData = JSON.parse(e.data);
handleData(parsedData);
};
ws.onopen = function(){
console.log('Websocket open');
}
Backend (uses ws and express, the most common WebSocket client web framework for NodeJS)
const SocketServer = require('ws').Server;
const router = require('express').Router();
const server = express()
.use('/', router)
.listen(3000, () => console.log('Listening on 3000'));
const wss = new SocketServer({ server });