Skip to main content

NOdejs birbal

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




Comments

Popular posts from this blog

Coding Interview Questions Set 1

From this article, I will be sharing with you all a series of articles on coding interview questions. So please stay connected for the latest set of questions. It will be a good brainstorming exercise and will also prepare you for coding interviews and will definitely boost your confidence. So let's start, 1)Reverse of a string with only O(1) extra memory. Solution: var reverse = function(string) {     let result = ''     for(let i= string.length -1; i >= 0; i--){         result += string[i];     }     return result; }; 2)Fizz Buzz: Write a program that will accept a number n and will output number till n but for multiples of three it should output “Fizz” instead of the number and for the multiples of five output “Buzz”. For numbers which are multiples of both three and five output “FizzBuzz”. Solution: var fizzBuzz= function(n) {     const arr=[]     for(i=1; i<=n; i++){ ...

JavaScript: Debouncing | Flipkart UI Interview Question.

To understand this programming practice will go with a quick example. We all do online shopping and we do search for products on Flipkart on the search bar. So when we type on search bar i.e on every keypress we are actually giving API requests to the server, which in response gives us suggestions. Actually, it's a time-consuming task and may degrade the performance of the webpage. So to improve the performance we use debounce function which actually acts as a controller which reduces the API request to the server on keypress event. In simple terms, we are giving API request only after a certain amount of time between two keypress events. A debounce is a higher-order function. Higher-order function: A function that returns another function. Let's dive deep: HTML Code: <input type="text" onkeyup="searchProducts()"/> Consider this as a search bar for Flipkart. On any keypress, we are calling searchProducts() function. Javascri...

Node.js: Bundling your Node.js application to single executable for Windows.

In this article, we will see how to bundle Node.js application to a single executable for Windows. What's the need? Well recently, I had taken a work where I needed to convert pdf's(Of similar format) to excel sheet. So I was reading the pdf's from a folder in desktop and I was storing the output excel sheet into a separate folder on the desktop. I used Node.js for the program. Now the client wanted it to install the program on 25 windows machine and his budget was really low. So it was also not possible for me to install node.js for 25 machines and then install the required dependency for each one. One of the solution: While I was searching for an easy solution I found this amazing npm module pkg . This module can make your node.js app work like plug and play type. No need to install Node.js on the client machine or any other dependency.  It helps to make a commercial or trial version of your node.js application without exposing the source code. I found ...