🔐 JWT Authentication API

A secure REST API implementation for user authentication using JSON Web Tokens (JWT).

✨ Features

• 📝 User registration (sign-up)
• 🔑 User authentication (sign-in)
• 🚪 User sign-out
• 🔒 Secure password hashing using bcrypt
• 🎟️ JWT-based authentication
• 🗄️ MongoDB integration
• ⚠️ Error handling middleware
• ✅ Input validation

📋 Prerequisites

• 📦 Node.js (v14 or higher)
• 🗃️ MongoDB database
• 📥 npm or yarn package manager

🚀 Installation

1. Clone the repository:

git clone <repository-url>
cd user-authenticator

2. Install dependencies:

npm install

3. Create a .env file in the root directory with the following variables:

PORT=8000
DB_URI=your_mongodb_connection_string
JWT_SECRET=your_jwt_secret_key
JWT_EXPIRES_IN=1d

💻 Usage

Development

npm run dev

Production

npm start

🛣️ API Endpoints

Authentication

Method	Endpoint	Description
POST	/api/v1/auth/sign-up	Register a new user
POST	/api/v1/auth/sign-in	Authenticate user and get token
POST	/api/v1/auth/sign-out	Sign out user

Request Bodies

Sign Up

{
  "username": "username",
  "password": "Password123!"
}

Sign In

{
  "username": "username",
  "password": "Password123!"
}

🛡️ Security Features

• 🔒 Password validation (minimum 8 characters, uppercase, lowercase, special character)
• 👤 Username validation (8-50 characters)
• 🍪 HTTP-only cookies
• 🔑 Secure password hashing
• 💾 MongoDB transaction support
• 🧹 Input sanitization
• 🌐 CORS enabled

⚠️ Error Handling

The API includes comprehensive error handling for:

• ❌ Validation errors
• 🔄 Duplicate entries
• 🚫 Authentication failures
• 💽 Database errors
• 🔧 Server errors

🛠️ Technology Stack

• ⚡ Express.js
• 🍃 MongoDB with Mongoose
• 🎟️ JSON Web Tokens (JWT)
• 🔐 bcrypt