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1)Module object in nodejs to provide encapsulation?

In Node.js, encapsulation can be achieved using the module system provided by CommonJS. CommonJS is a module system for JavaScript that allows you to encapsulate code into separate modules with their own scope, thereby preventing pollution of the global namespace and providing a way to organize and structure your code.


Here's a basic example of how you can use CommonJS modules for encapsulation in Node.js:


Create a module file (myModule.js):

// myModule.js
let privateVariable = 'I am private';

function privateFunction() {
    console.log('This is a private function');
}

module.exports = {
    publicVariable: 'I am public',
    publicFunction: function() {
        console.log('This is a public function');
        privateFunction(); // Private function can be accessed within the module
    }
};

2)How to handle concurrent request in sockets?

In Node.js, handling concurrent requests in sockets is accomplished through the event-driven, non-blocking I/O model. Let's break down what each of these concepts means:

  1. Event-Driven: Node.js is based on an event-driven architecture. This means that instead of blocking and waiting for I/O operations (such as reading from or writing to a socket) to complete, Node.js registers callback functions to be executed when certain events occur. These events can include incoming data on a socket, a socket connection being established, a timer expiring, or an asynchronous operation completing.

3)Which event is fired when connect to socket?

In Node.js, when you connect to a socket, the 'connect' event is fired. This event is emitted by a net.Socket object when a connection is successfully established to a TCP server.


Here's an example of how you can listen for the 'connect' event in Node.js:

const net = require('net');


// Create a new socket and connect to a TCP server

const socket = net.createConnection({ port: 3000, host: 'localhost' });


// Listen for the 'connect' event

socket.on('connect', () => {

    console.log('Connected to server');

});


// Handle errors

socket.on('error', (err) => {

    console.error('Socket error:', err);

});


How to handle high io in nodejs?

How to handle 3 party api securely in nodejs?

Where to use buffer class in nodejs?

What is difference between import and require?

https://medium.com/@chamin.njay/require-vs-import-in-node-js-abdf5427d7b0




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