🚀 Stellar E-Commerce Backend API

A fully scalable, secure, enterprise-grade, and production-ready E-Commerce Backend API built with modern backend architecture and best practices.

Designed for:

• Production Applications
• Real MERN Stack Projects
• Enterprise-Level Scaling
• Secure Authentication Systems
• High Performance APIs

---

🌍 Live Architecture Overview

Frontend (React / Next.js)
        ↓
Axios API Layer
        ↓
Express.js REST API
        ↓
Controllers
        ↓
Services Layer
        ↓
MongoDB Database
        ↓
JWT Authentication + Cookies

---

⚡ Tech Stack

Technology	Purpose
Node.js	JavaScript Runtime
Express.js	Backend Framework
MongoDB	NoSQL Database
Mongoose	MongoDB ODM
JWT	Authentication
bcryptjs	Password Hashing
cookie-parser	Cookie Handling
Helmet	Security Headers
Compression	Response Compression
Morgan	Request Logging
HPP	HTTP Parameter Pollution Protection
express-rate-limit	API Rate Limiting
express-mongo-sanitize	MongoDB Injection Protection

---

📁 Production Folder Structure

src/
├── config/
│   ├── db.js
│   └── constants.js
│
├── controllers/
│   ├── auth.controller.js
│   ├── product.controller.js
│   ├── order.controller.js
│   └── user.controller.js
│
├── middlewares/
│   ├── auth.middleware.js
│   ├── error.middleware.js
│   ├── validate.middleware.js
│   └── rateLimiter.middleware.js
│
├── models/
│   ├── user.model.js
│   ├── product.model.js
│   ├── order.model.js
│   ├── coupon.model.js
│   └── review.model.js
│
├── routes/
│   ├── index.route.js
│   ├── auth.route.js
│   ├── product.route.js
│   ├── order.route.js
│   └── user.route.js
│
├── services/
│   ├── email.service.js
│   └── payment.service.js
│
├── utils/
│   ├── ApiResponse.js
│   ├── ApiError.js
│   ├── asyncHandler.js
│   └── generateAuthToken.js
│
├── validators/
│   ├── auth.validator.js
│   └── product.validator.js
│
├── app.js
└── server.js

---

🧠 Architecture Principles

This project follows:

✅ MVC Architecture
✅ Separation of Concerns
✅ Reusable Services
✅ Modular Structure
✅ Clean Code Practices
✅ Enterprise Scalability
✅ Production Security Standards

---

🔐 Authentication System

This backend uses:

JWT + HTTP Only Cookies

Authentication Flow:

User Login
    ↓
Validate Credentials
    ↓
Generate JWT
    ↓
Store JWT in Secure HTTP Only Cookie
    ↓
Access Protected Routes

---

🍪 Cookie Authentication

JWT token is stored inside:

HTTP Only Secure Cookie

Benefits:

✅ More Secure
✅ Prevents XSS Attacks
✅ Safer Than LocalStorage
✅ Production Recommended

---

🛡️ Security Features

This backend includes enterprise-level security middleware.

Middleware	Purpose
helmet	Secure HTTP headers
compression	Compress response size
morgan	API request logging
express-rate-limit	Prevent API abuse
hpp	Prevent parameter pollution
express-mongo-sanitize	Prevent MongoDB injection
cookie-parser	Read cookies

---

⚡ Security Flow

Client Request
      ↓
Helmet Security
      ↓
Rate Limiting
      ↓
Mongo Sanitize
      ↓
HPP Protection
      ↓
Validation Middleware
      ↓
Authentication Middleware
      ↓
Controller
      ↓
Database

---

📦 Installation

1️⃣ Clone Repository

git clone <repository_url>

---

2️⃣ Move Into Project

cd backend-E-commece

---

3️⃣ Install Dependencies

npm install

---

🔐 Environment Variables

Create .env file in root directory.

PORT=5000

NODE_ENV=development

MONGO_URI=your_mongodb_connection

JWT_SECRET=your_super_secret_key

CLIENT_URL=http://localhost:5173

---

▶️ Run Application

Development

npm run dev

---

Production

npm start

---

🌐 API Base URL

http://localhost:5000/api/v1

---

🔑 Authentication APIs

---

Register User

Endpoint

POST /api/v1/auth/register

Request Body

{
  "username": "faiq",
  "email": "faiq@example.com",
  "password": "123456"
}

Response

{
  "success": true,
  "message": "User registered successfully",
  "data": {
    "_id": "123",
    "username": "faiq",
    "email": "faiq@example.com",
    "role": "user"
  }
}

---

Login User

Endpoint

POST /api/v1/auth/login

Request Body

{
  "email": "faiq@example.com",
  "password": "123456"
}

---

Logout User

Endpoint

POST /api/v1/auth/logout

---

🧠 Backend Request Lifecycle

graph TD

A[Client Request] --> B[Express Server]

B --> C[Middlewares]

C --> D[Validation]

D --> E[Authentication]

E --> F[Controller]

F --> G[Service Layer]

G --> H[MongoDB Database]

G --> I[External APIs]

H --> J[Response]

I --> J

Loading

---

🔥 Frontend → Backend Login Flow

🔥 Frontend → Backend Login Flow

flowchart TD

A[User Opens Login Page] --> B[Login.tsx]

B --> C[User Enters Email & Password]

C --> D[handleSubmit Function]

D --> E[Zod Validation]

E -->|Invalid| F[Show Validation Error]

E -->|Valid| G[useAuth login]

G --> H[AuthContext.tsx]

H --> I[loginUser]

I --> J[auth.api.ts]

J --> K[Axios Instance]

K --> L["/api/v1/auth/login"]

L --> M[auth.route.js]

M --> N[auth.controller.js]

N --> O[Find User By Email]

O --> P[Compare Password]

P -->|Invalid| Q[Return 401 Error]

P -->|Valid| R[Generate JWT]

R --> S[Set JWT Cookie]

S --> T[Send Success Response]

T --> U[Axios Response Interceptor]

U --> V[Set User State]

V --> W[Navigate to Home]

W --> X[User Logged In Successfully]

Loading

---

⚡ Production Optimizations

Included optimizations:

✅ Response Compression
✅ Secure HTTP Headers
✅ API Request Logging
✅ Global Error Handling
✅ JWT Cookie Authentication
✅ Validation Layer
✅ Rate Limiting
✅ Mongo Injection Protection
✅ HTTP Parameter Pollution Protection

---

❌ Global Error Handling

Centralized error handling implemented.

Example Error Response:

{
  "success": false,
  "message": "Invalid credentials"
}

---

🧪 Testing

Future testing support:

• Jest
• Supertest
• Integration Testing
• API Testing

Test folder:

src/test

---

🚀 Deployment Ready

Compatible with:

✅ Render
✅ Railway
✅ VPS
✅ AWS
✅ DigitalOcean
✅ Docker
✅ Vercel Backend
✅ Nginx Reverse Proxy

---

📌 Future Improvements

Planned enterprise features:

• Refresh Tokens
• Email Verification
• Forgot Password
• Role-Based Access Control
• Product Management APIs
• Order Management
• Payment Gateway Integration
• Redis Caching
• Swagger Documentation
• CI/CD Pipeline
• Dockerization
• Microservices Support

---

👨‍💻 Developer

Muhammad Faiq

Full Stack MERN Developer

---

📄 License

This project is licensed under the MIT License.