💸 Expense Tracker – Full Stack Application

A full-stack Expense Tracker application that allows users to record daily expenses and view them in real time.
The project demonstrates frontend–backend integration, REST API design, and AWS DynamoDB usage for persistent storage.

This project was built to understand end-to-end application development and cloud-native architecture.

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🧠 What Problem This Project Solves

Managing daily expenses is often done manually or using complex tools.
This project provides a simple, lightweight expense tracking system where:

• Users can add expenses with title, amount, and date
• Data is stored persistently in AWS DynamoDB
• Expenses are fetched dynamically via REST APIs
• The UI updates automatically after every change

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🧱 Tech Stack

Frontend

• React (Create React App)
• Axios
• HTML / CSS

Backend

• Spring Boot
• REST APIs
• AWS SDK for DynamoDB
• Deployed on AWS Elastic Beanstalk

Database

• AWS DynamoDB (NoSQL)
  • Scalable
  • Schema-less
  • Managed by AWS

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🔧 Backend Overview (Spring Boot + DynamoDB)

Responsibilities

• Expose REST APIs for expense management
• Persist and fetch data from DynamoDB
• Handle CORS and request validation

API Endpoints

Method	Endpoint	Description
GET	/api/expenses	Fetch all expenses
POST	/api/expenses	Add a new expense

Example Request Payload

{
  "title": "Coffee",
  "amount": 150,
  "date": "2025-01-12"
}

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🎨 Frontend Overview (React)

Responsibilities

• Collect user input
• Display expenses in a table
• Call backend APIs using Axios
• Update UI automatically after data changes

API Configuration (App.js)

const API = "http://localhost:8080/api/expenses";

For deployed backend:

const API = "http://<elastic-beanstalk-url>/api/expenses";

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▶️ Run the Project Locally

Backend

cd backend
mvn spring-boot:run

Runs On:

http://localhost:8080

Frontend

cd frontend
npm install
npm start

Runs On:

http://localhost:3000

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🏗️ Build Frontend for Deployment

npm run build

Output:

build/
├── index.html
├── asset-manifest.json
└── static/

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🛠️ Key Learnings from This Project

• Designing RESTful APIs
• Integrating React with Spring Boot
• Using AWS DynamoDB with Spring Boot
• Handling cross-origin requests (CORS)
• Deploying backend services on AWS

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👨‍💻 Author

Harshvardhan Rao
Java Backend & Full-Stack Developer
Focused on building scalable, cloud-native systems 🚀