Here are the steps to create an EC2(Amazon Elastic Compute Cloud), set up your Git remote repository in EC2 and connect to the remote repo from your local machine. Some explanations are provided for better understanding. AWS Elastic Compute Service(EC2) is IaaS(Infrastructure as a Service).   PART 1 – Creating and connecting to AWS EC2 Virtual Machine instance.   STEP 1  – Go to AWS console. STEP 2 – goto services, ...



Understanding Cloud Deployment Models. Cloud Part – 2
Cloud , Uncategorized / November 21, 2019

For part 1 of this series visit the following link What is Cloud Computing and Why? Cloud Part – 1   Cloud Deployment Models represent the types of cloud environments used by business organizations depending upon access, ownership, and size. There primarily  4 types of cloud deployment models Public Cloud Private Cloud Hybrid Cloud Community Cloud All these models provide various IT Resources as services Public Cloud A Public c...

Understanding Cloud service models IaaS, PaaS and SaaS – Cloud 3
Cloud , Uncategorized / December 3, 2019

You might have heard acronyms like IaaS, PaaS, SaaS, what do they actually mean? what are cloud service models?. This is the third part of the Cloud Series and aims to provide an answer to the above questions. This article will provide you with an overview of cloud service delivery models so that you can choose which service model is best suited for your business application.   Cloud service models Cloud service models are models,...

Difference between tilde (~) and caret (^) in package.json, Semantic Versioning of npm packages and npm audit for vulnerability fixes
interview questions , Uncategorized / November 27, 2019

In the package.json files of  Node.js applications, the dependencies are added specifying their version. Sometimes these version numbers can be preceded by tilde (~) and caret (^) characters. What do they actually intent and what is the difference between them?     Semantic Versioning of npm packages Consider a version of a package like 1.2.3                It is of the form MAJOR.MINOR.PATCH MAJOR in version is updat...

Understanding Map object in JavaScript

Map Hold key-value pairs Remember the order of insertion. Can have objects or primitive values as key or value. Map is a JavaScript object which can hold key-value pairs  and remember the order of insertion. Maps inherit from  Map.prototype. Map.prototype.constructor returns the constructor function that created an instance’s prototype. A new Map is created using the map constructor in the following way. [crayon-5e7fe12f242...

Q: Handling errors while using Async/Await (JavaScript ES8)

This article aims at providing an insight into handling errors while using async-await. In the below example, a  function TestPromise will return a promise.The promise will give an error and get rejected if the value of the variable budget is less than 20000. The promise will always get rejected as we initialize the value of  budget to be 10000. A function calltestAPromise calls the function TestPromise.   [crayon-5e7fe12f...

Beginners guide to installing and setting up MongoDB and GUI for MongoDB in Windows Machine
MongoDB , databases , Uncategorized / September 26, 2019

This is a step by step tutorial for installing MongoDB and setting up a GUI for MongoDB on Windows OS   Step – 1 Check whether MongoDB is already installed in the system To check whether MongoDB is already installed in the system, and the PATH variable is configured, use the following command. This will output the version of MongoDB . [crayon-5e7fe12f2a536105389011/] The following command will output the Mongo shell version [...

Node.js – tools/packages/practices for building a secure,high performance API with quality code

Contents >Code standard and styling >Security >Performance         In this article, we will take a look at some important aspects to be considered while developing Node.js applications and the tools/packages/practices that can be used to achieve them. Understanding and using these will help you in building a secure web application that is well structured and well documented and has a very high performance. C...

Guidelines for building a secure Web application/Mobile application – Part 1 Front-end

Security is the biggest concern while building web applications. Most of the web applications handle a lot of sensitive data and it is necessary to provide adequate security to protect this data from perpetrators. This series of articles discuss various security issues, types of attacks and guidelines to be followed for building a  secure application. Front-end    The basic security features that should be implemented in every w...

Check for duplicates in JavaScript Array of Objects
Javascript , Express.js , Uncategorized / July 28, 2019

How to check whether an Array of Objects contain duplicates by key Consider an Array of student Objects with each object having a key id. We have to perform a validation whether multiple objects with the same Id is present in the Array or not. [crayon-5e7fe12f47ec4745171695/] The above are Arrays of student Objects, one with duplicate id value and one without duplicate id value. To get the  Ids present in the Arrays we need to use the ...

Web Storage – A comparative study of Local Storage,Session Storage,Cookies,IndexedDB and WebSQL
Javascript , databases , Uncategorized / July 10, 2019

Storages in browsers – Web Storage Web Storage is the storage mechanism that allows Web applications to store data in Web Browsers. The various storage types include Local Storage, Session Storage, Cookies, IndexedDB, Web SQL. These storages are supported by most of the modern-day web browsers and are standardized by the World Wide Web Consortium. Web Storage lets a web application to store data which in turn helps in the effectiv...