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Introduction ( TL;DR )

If you are familiar with Google Cloud Platform or AWS, you must be aware of famous software-based load balancers, all they do is, efficient distribution of network or application traffic across multiple servers. They usually sit in between client devices and backend servers.

Now there are several options for selecting a Load Balancer from popular Cloud Providers. Today, let's discuss the differences between a Load Balancer based on layers of the OSI Model: Layer 4 and Layer 7.

Enough intro…

Layer 4 is nothing but the Transport Layer of the OSI Model. …

We all might know REST stands for Representational State Transfer, which is nothing but a Software Architectural Style which is some set of rules to create web services. RESTful services have mainly designed for loosely coupled systems over HTTP.

Let’s see some of the best practices that we can follow to design REST API for any client…


As the name suggests similar endpoints should behave in a similar way. Ideally, someone looking into your API should be able to make a guess on what the purpose of your API is.

It’s always better to synonymize a resource with a web…

There can be many scenarios where people may want to add Real-Time feature to their project.

Consider below scenario —

You are building a realtime news feed that updates data whenever there is any change or addition without refreshing the whole page.

Main Implementation Idea

The main technology used for this purpose is Websocket. They allow a long-held single TCP socket connection to be established between the client and server which allows for bi-directional, full-duplex, messages to be instantly distributed with little overhead resulting in a very low latency connection.

Enough Theory! Let's implement it

  • We are mainly using ApolloServer version 2.9 …

Many of us have come across the term called Shadow DOM either in some tutorials, docs or in the latest JS frameworks. Let's demystify this today…

What shadow dom really is?

Shadow DOM refers to the ability of the browser to include a subtree of DOM elements into the rendering of a document, but not into the main document DOM tree. In very simple terms, “It is DOM within a DOM”

Shadow DOM is a new DOM feature that helps you build components. You can think of shadow DOM as a scoped subtree inside your element.

What is Elastic Beanstalk?

With Elastic Beanstalk, you can quickly deploy and manage applications in the AWS Cloud without having to learn about the infrastructure that runs those applications. Elastic Beanstalk reduces management complexity without restricting choice or control. You simply upload your application, and Elastic Beanstalk automatically handles the details of capacity provisioning, load balancing, scaling, and application health monitoring.

What environment/programming language does it support?

Currently, Elastic Beanstalk supports Node.js, Python, Go, Ruby, PHP, Java, .NET.

Anyway, if you don't see your environment as one of the supported environment, you can create a custom environment using Docker.

Steps to configure AWS EB CLI

1. Install AWS CLI


To use Elastic Beanstalk CLI, you have to first install…

Release process

We as a developer always try to follow best practices while writing code, developing websites or developing an Android or IOS app.

Sometimes development workflow becomes too complex and with a lot of tools and techniques out there, it becomes confusing for a developer to choose from various development patterns.

Here are some mistakes we generally make while delivering or developing web-based products…

I feel like this is the most ignored point of web development.

We often test our code with staging and production environment before deploying to production. We also write automated tests and follow TDD pattern just to…

Recently passed the AWS Certified Developer — Associate exam (June 2018 version) on March 8th, 2019 with 891 marks.

No Doubt AWS CDA (June 2018) is one of the most valuable cloud certifications for developers. But wait! It’s not so easy at all to pass it without proper preparation. It’s full of tricky, scenario based questions.

From the June 2018 version, they made the certification exam in a way that whoever passes the exam, has sound knowledge on AWS Services and Best Practices.

It validates an examinee’s ability to:

  • Demonstrate an understanding of core AWS services, uses, and basic AWS architecture best practices.
  • Demonstrate proficiency in developing, deploying, and debugging cloud-based applications using AWS.

Earlier, people used to get…

Google cloud CDN is — low latency, distributed content delivery solution. It has more than 100 POP (Point of presence) to make your assets highly available.

The Cloud CDN content delivery network works with HTTP(S) load balancing to deliver content to your users. The HTTP(S) load balancing configuration specifies the frontend IP addresses and ports on which Cloud CDN receives requests and the backends that originate responses to those requests.

We will see how the above definition works step and step, and also we will configure a cdn using GCloud Platform with SSL ( HTTPS) support.


— — — —…

While deploying a NodeJS app in production we always think about scalability. In fact, we know node being an asynchronous single threaded io, it blocks events loop while processing a request.

To avoid those type of performance bottlenecks, we often use a concept called load balancing to create a distributed architecture.

Implementing Load balancer with node js

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There are many ways to achieve this…

  • If deploy you app on App Engine in Google Cloud Platform, you’ll find it extremely easy to…

Functions can use objects to remember the results of previous operations, making it possible to avoid unnecessary work. This optimisation is called memoization. JavaScript’s objects and arrays are very convenient for this.

Let’s understand this by writing a programme to compute a fibonacci numbers.

var fibonacci = function (n) {
return n < 2 ? n : fibonacci(n − 1) + fibonacci(n − 2);

for (var i = 0; i <= 10; i += 1) {
console.log('// ' + i + ': ' + fibonacci(i));

In the above scenario, the computation of fibonacci is not optimised because the…

Subhajit Dutta

Full Stack Software Developer

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