Ecommerce Backend

A Production-Ready Spring Boot E-Commerce REST API

Ecommerce Backend is a secure, scalable RESTful backend system built using Spring Boot, implementing authentication, cart management, order processing, optimistic locking, and role-based access control—designed using clean architecture principles.

Focused on real-world backend practices such as JWT authentication, transactional consistency, DTO mapping, and layered architecture, this project demonstrates enterprise-grade backend development using Java and Spring.

Features • Architecture • Tech Stack • Getting Started

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Project Overview

Many beginner backend projects only implement basic CRUD operations without handling real-world concerns like authentication, transactional integrity, or concurrency control.

Ecommerce Backend was built to demonstrate:

• Secure JWT-based authentication
• Role-based authorization (ADMIN / USER)
• Cart-to-order transactional workflow
• Optimistic locking for inventory protection
• DTO-based API design (no entity exposure)
• Clean layered architecture

This project focuses on correct domain modeling, consistency, and production-level backend structure.

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Architecture & Flow

graph TD
    A[Client / Frontend] --> B[Controller Layer]
    B --> C[Service Layer]
    C --> D[Repository Layer]
    D --> E[(Database)]
    C --> F[Security Layer - JWT]
    F --> B

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Architectural Highlights

• Layered Architecture (Controller → Service → Repository)
• DTO Pattern for request/response separation
• JWT Authentication & Role-Based Authorization
• Transactional Order Processing
• Optimistic Locking for Inventory Safety
• Global Exception Handling

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Key Features

Authentication & Authorization JWT-based authentication Role-based access control (ADMIN / USER) Secure password hashing Protected endpoints using Spring Security	Product Management Create products (Admin only) Delete products (Admin only) Fetch product list Inventory tracking with stock management
Cart Management Add product to cart Remove product from cart View cart items Quantity validation Price captured at time of adding (priceAtAdd logic)	Order Processing Convert cart into order Transaction-safe order placement Stock validation before order confirmation Order entity linked with user
Inventory Safety Optimistic locking using @Version Prevents overselling during concurrent orders Automatic rollback on failure	Clean API Design DTO-based input/output Validation annotations Meaningful HTTP status codes Centralized exception handling

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Tech Stack & Architecture

Core Technologies

• Language: Java
• Framework: Spring Boot
• Build Tool: Maven
• Database: MySQL / H2 (configurable)
• ORM: Spring Data JPA (Hibernate)

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Spring Modules Used

• Spring Web – REST API development
• Spring Data JPA – Database abstraction
• Spring Security – Authentication & Authorization
• Validation API – Request validation
• JWT – Stateless authentication

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Database Design

Core Entities:

• User
• Product
• Cart
• CartItem
• Order
• OrderItem

Key Relationships:

• User → OneToMany Orders
• User → OneToOne Cart
• Cart → OneToMany CartItems
• Order → OneToMany OrderItems
• Product → Optimistic Locking via @Version

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Getting Started

Clone the Repository

git clone https://github.com/iRahmanG/Ecommerce-Backend.git

Configure Database

Update application.properties:

spring.datasource.url=jdbc:mysql://localhost:3306/ecommerce
spring.datasource.username=your_username
spring.datasource.password=your_password
spring.jpa.hibernate.ddl-auto=update

Or use H2 for quick testing.

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Run the Application

mvn spring-boot:run

Application will start at:

http://localhost:8080

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Example API Flow

1. Register User
2. Login → Receive JWT
3. Create Product (Admin only)
4. Add Product to Cart
5. Place Order
6. Inventory updated safely via optimistic locking

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Learning Outcomes

This project demonstrates:

• Secure JWT-based authentication
• Role-based authorization in Spring Security
• Clean layered architecture design
• Transaction management using @Transactional
• Optimistic locking for concurrency handling
• DTO-based REST API design
• Proper entity relationships in JPA
• Business logic validation inside service layer

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Future Enhancements (Planned)

• Refresh Token support
• Product search & filtering with pagination
• Payment gateway integration (Stripe / Razorpay)
• Wishlist functionality
• Product reviews & ratings
• Redis caching for performance
• Swagger / OpenAPI documentation
• Unit & Integration testing

(Planned for next development phase)

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Author

Maksud Rahman Backend Developer | Java & Spring Boot

GitHub: https://github.com/iRahmanG

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⭐ If this project helped you understand backend architecture, consider starring the repository!

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