DEV Community: SushantDhiman2004

Understanding RabbitMQ in simple terms

SushantDhiman2004 — Sat, 28 Feb 2026 14:19:07 +0000

Hi, I hope you all are doing well. Recently I was exploring RabbitMQ, and I found it fascinating. Previously I've used Kafka. RabbitMQ is very different from Kafka. This article is mostly useful for beginners or people who haven't used RabbitMQ. If you are an experienced developer, you might not find anything new in this post.

What is RabbitMQ?

RabbitMQ (Rabbit Message Queueing) is an Open Source message broker. It is used by applications to interact asynchronously. Simplest use case of RabbitMQ can be establishing a communication between multiple micro-services.

Those who are new to message brokers or message queue read this to understand them. Experienced persons can skip.

What is a message queue?

Let's say you need an e-commerce solution. When any user places an order, 3 things happen: checkout handling, email sending and inventory update. You have a monolithic system where all 3 things happen sequentially, and on average it takes 5 seconds. Your user needs to hang on for 5 seconds. Later you decide to address this problem and break your system into 3 microservices.

Checkout Service
Email Service
Inventory Service

Now each service will handle a particular thing. But the user still needs 5+ seconds because things will still happen sequentially. This is where the message broker/message queue comes into play. You will modify your application in this way:

When the checkout service confirms payment, just return success to the user.
Publish a message with order details in a message queue.
Email & Inventory service will continuously wait for messages in the queue.
Both microservices will do their task in the background without forcing the user to wait.

Message Queues provide a reliable way for micro-services to communicate with each other.

Read complete post on my blog.

C actually don't have Pass-By-Reference

SushantDhiman2004 — Sat, 25 Oct 2025 05:53:43 +0000

Recently I decided to dive into low-level programming, and of course I started with revising pointers. I picked up the free e-book Extreme C by Kamran Amini and found an interesting example in it.

void func(int* a) { int b = 10; *a = 5; a = &b; }

Above function is:

Receiving a pointer to variable “a”.
Initializing a new variable “b”.
Dereference pointer “a” and changing it’s value to 5.
Finally replacing the address of “a” with “b”.

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gRPC Microservices in Go with Hexagonal Architecture – Part 1

SushantDhiman2004 — Fri, 03 May 2024 13:06:49 +0000

Hello everyone! Welcome to this ultimate series of microservices with gRPC and Golang. In this series, we are going to discuss everything that you need to know to build microservices using gRPC. Also, we are going to develop everything by following the concept and practices of hexagonal architecture. I will start by simply and keep explaining as we move forward. If you did not understand something keep reading as you will get a better understanding once you have gone through all the content.

The post is originally published on my blog SushantCodes.tech kindly read it there if you want.

What are Remote Procedure Calls (RPC)?

A remote processor call is a protocol that allows us to call a function from our computer on another computer. This is also the best concept of distributed systems. gRPC is a further extended and customized version of RPC that has its benefits. It was developed by Google.

What are distributed systems?

A distributed system is the combination of several computers that are connected in a network and communicate via message passing. For a more realistic example, you can think of it as software being divided into different independent parts and each part being hosted on a separate computer. All the parts and computers communicate via messages to achieve a common goal.

What is a microservices architecture?

Before understanding microservices let’s understand Monolithic. In traditional software environments, all the components of software are hosted on the same server. But the problem arises when a single component fails which leads to the filling of the entire system. So I know the overcome that microservices architecture arises which empowers the concept of dividing software into different parts known as services and hosting it service on a different computer. If any of the services fails then all other services will still work. It is designed in such a way that these services are least interdependent.

Prerequisites: –

For this post, I am assuming that you already know how to make REST APIs because that is the basic concept of backend development. If you don’t know how to make simple APIs, then I would recommend that you first go and learn those concepts.

Aim for This Series:

In this series, we aim to create two different microservices that will be completely independent, and they will communicate with each other using gRPC. Although we can do this thing, we are also using rest architecture, but we want to learn something new. That’s why we are using gRPC.

Let’s Start Coding

Create a new go project by running the following command: –

go mod init order

I am calling this package as “order” because our one microservice will be for order creation and another microservice will be for payment processing.

Create Folders
Now let us create some folders to organize our code. Below is the oldest structure of hexagonal architecture for microservices. You have to create the same folder and I will explain each of them in detail.

├── cmd
├── config
└── internal
    ├── adapters
    │   ├── db
    │   ├── grpc
    │   └── payment
    ├── application
    │   ├── api
    │   └── domain
    └── ports`

What is Hexagonal Architecture?

Hexagonal architecture is the way of designing software by splitting it into two parts. The first part is known as Business Logic or Core and the second part is known as Ports.

Core (Business Logic): As its name suggests this part handles all the core logic of the software and fulfills the needs and requirements of the software. This part does not interact with the external world at all.
Ports: There are electrical ports in your home and you can plug any appliance and your appliance starts working. But one thing to note here is that your appliance does not need to know what’s inside the port and how everything is working. The same thing happens in hexagonal architecture where ports are the Gateway for external communication. For example, if a database on to communicate with the software or there is a user interface that wants to interact with the software then it is done by ports.

Create Data Structure For Order

Create a new file at internal/application/domain and name it as domain.go. Then add the following code to that.

package domain

import "time"

type OrderItem struct {
    ProductCode string  `json:"product_code"`
    UnitPrice   float32 `json:"unit_price"`
    Quantity    int32   `json:"quantity"`
}

type Order struct {
    ID         int64       `json:"id"`
    CustomerID int64       `json:"customer_id"`
    Status     string      `json:"status"`
    OrderItems []OrderItem `json:"order_items"`
    CreatedAt  int64       `json:"created_at"`
}

func NewOrder(customerID int64, orderItems []OrderItem) Order {
    return Order{
        CustomerID: customerID,
        Status:     "Pending",
        OrderItems: orderItems,
        CreatedAt:  time.Now().Unix(),
    }
}

func (o *Order) TotalPrice() float32 {
    var totalPrice float32
    for _, val := range o.OrderItems {
        totalPrice += val.UnitPrice
    }
    return totalPrice
}

The above defines a simple structure for an order that is being placed by the customer. Think about your Amazon cart while reading this code you will understand automatically. There is a structure “OrderItem” that represents a single order item and another structure “Order” that represents customer details and all the items that he is ordering. Below that we have affection to create new orders and another function to get a total price for the current order.

Create API Interface:

Go to the ports folder create a new file with the name API.go and add the following code to that file.

package ports

import "order/internal/application/domain"

type APIPort interface {
    PlaceOrder(domain.Order) (domain.Order, error)
}

This code is an interface for the API that we are going to build. You will understand the need for this when we move further in this series.

Implementing APIPort

Now we have to implement the interface that we defined above. It is the core logic of our microservice. As we are making an “order” microservice we are going to write some logic to get order requests from the user, save the order in the database, and proceed with payment. This all stuff is a long thing to do so I will keep it short and simple for this part of the series. Currently, my main focus is to get microservices ready and do communication between them. Later we can do some database stuff.

Go to internal/application/api and create a new file “api.go”. Add the following code to this file.

/*
    PoF - This is the core logic of the service.
*/

package api

import (
    "order/internal/application/domain"
    "order/internal/ports"
)

// This struct will implement ports/api.go interface.
type Application struct {}

func NewApplication() *Application {
    return &Application{}
}

func (a Application) PlaceOrder(order domain.Order) (domain.Order, error) {
    fmt.Println("Placing Your Order")

        /*
        Database stuff and communication with Payments Microservice will be done here.
        */

    return order, nil
}

Wrap Up

Okay, now that’s enough for this part I guess. In the next part, we are going to set up gRPC and run this API. Also, we will add database logic to save order. But before that, I would like you to drop a comment if you like this post. It will give me the motivation to create more well-defined content for the next post. Thank you.``

Help me validating my Micro Startup Idea

SushantDhiman2004 — Sun, 04 Feb 2024 09:52:38 +0000

Hey fellow learners!

I'm excited to share with you a new project I've been working on that I believe has the potential to revolutionize how we approach online learning, especially on platforms like Udemy. As a passionate learner myself, I've often found it challenging to stay consistent with my Udemy courses and effectively organize my notes as I go along.

What is it?

This platform aims to streamline your Udemy learning experience by offering a range of features to keep you on track and engaged throughout your courses. From progress tracking to note-taking and community interaction, this platform is your all-in-one companion for mastering new skills and concepts.

Key Features:

Course Progress Tracking: Keep tabs on your progress within each Udemy course, marking lectures, quizzes, and assignments as completed to stay on top of your learning goals.
Reminder System: Receive customizable reminders to help you stay consistent with your learning schedule, ensuring you never miss a beat.
Note-taking Tool: Take detailed notes directly within the platform, complete with rich text formatting and support for code snippets, making it easy to review and reference key concepts later on.
Integration with Udemy: Seamlessly import your Udemy courses into the platform with just one click, and enjoy real-time syncing of your progress between platforms.
Progress Analytics: Gain valuable insights into your learning habits and progress over time, empowering you to make informed decisions about your study approach.
Community Interaction: Connect with fellow learners, participate in discussion forums, and join study groups to enhance your learning experience through collaboration and peer support.

Seeking Your Feedback:

Before finalizing the development of this platform, I'm eager to hear from you, the potential users! What do you think of this idea? Are there any features you'd like to see added or any improvements you'd suggest?

My Zocket SDE Intern Interview Experience

SushantDhiman2004 — Wed, 20 Dec 2023 23:11:45 +0000

Read here on my personal blog.

I made platform for developers to monitor their coding time.

SushantDhiman2004 — Fri, 01 Sep 2023 13:19:00 +0000

Maintain progress and flow of your coding.

My name is Sushant and in this post, I will be going to tell you about my product that I am going to release soon. This product is completely free and especially being developed for programmers like me. For the first month I have been working on a product called ProgFlow

What is ProgFlow?

It is a free platform that will monitor your coding activities. It will tell you how much time you are spending in coding, in which project you are spending your time, which language you are working in, and your average coding time.

The best thing about my platform is that you can set your coding goals and you can analyze when you are hitting your goal or not. You can share your coding reports with anyone on social media as well and you can show them to your recruiter to prove how much active you are in coding. This will help you to build your profile.

How ProgFlow monitor coding activities?

I have developed a VS Code extension that helps to monitor your coding time. It is completely open-source and secure to use. Your data will always be in the right hands.

Platform Tour

This is the main Dashboard of my platform. I have many more things to show but I would like to keep them for the next updates.

Price & Launch Date

I am aiming to launch this platform in the third week of September. This platform will be completely free for everyone.

Pre-Register Yourself 😃

If you want to try out my platform then you can pre-register yourself and an email will be sent to you when the platform launches. You can register yourself at https://progflow.tech

Final Words

I have spent a lot of time developing this thing for completely free and I will be spending that same time on upcoming updates and features also. I would like to hear your reviews and feedback. You can reach me via LinkedIn. Thank you and have a nice day.

How much will you rate my GitHub profile?

SushantDhiman2004 — Sat, 26 Aug 2023 01:39:53 +0000

Hi, I've designed my GitHub profile a little bit. I was curious if you give some time and rate it out of 10 😃😃.

Link: - Sushant's Profile

Best Campus Ambassador Programs for students.

SushantDhiman2004 — Sat, 16 Jul 2022 17:02:55 +0000

Hello Everyone, I have prepared a list of best Campus Ambassador Programs for students.
You can read complete list here

JavaScript this keyword simplest explanation.

SushantDhiman2004 — Sun, 29 May 2022 18:01:45 +0000

Read article here

Best Android Development Course 2022 Free + Paid

SushantDhiman2004 — Thu, 30 Dec 2021 04:51:12 +0000

Hello and welcome in this post we are going to discuss some of the best Android development courses for 2022. If you want to start your journey in Android development or if you want to advance your knowledge in Android development you can follow these courses. I have picked some of the best courses that are available online and listed them in this post. So let’s get started.
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AZ-900 Complete Guide | Resources | Strategy

SushantDhiman2004 — Tue, 28 Dec 2021 15:28:32 +0000

Hello & Welcome. My name is Sushant. In this post I’m going to talk about AZ-900 Exam. I recently passed out AZ-900 with just only 2 days preparation. In this post I’m going to tell How I prepared for AZ-900 and from where I go the resources for preparation. So without giving more intro let’s get started.

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I made quiz app in flutter.

SushantDhiman2004 — Sun, 28 Nov 2021 15:00:13 +0000

Hello & Welcome. I’m Sushant. In this post I’m going to share source codes of a Flutter Quiz app that I made with flutter. So let’s get started and dive into interesting content.

Read Complete Post & Get Source Code Here