🔐 MERN Authentication Service

A production-ready authentication service built with the MERN stack that supports multiple authentication providers, secure session management, and modern authentication best practices.

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✨ Features

Authentication

• User Registration
• User Login
• Secure Logout
• JWT Authentication
• HTTP-only Cookie Authentication
• Protected Routes

Social Authentication

• Google Sign-In
• GitHub Sign-In
• Automatic Account Linking
• Single Account Across Multiple Providers

Password Management

• Forgot Password
• Reset Password
• Secure Email-Based Password Reset

Security

• Password Hashing with bcryptjs
• JWT Authentication
• HTTP-only Cookies
• Secure Password Reset Tokens
• Input Validation
• Environment Variables
• OAuth 2.0 & OpenID Connect

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🛠️ Tech Stack

Frontend

• React 19
• TypeScript
• Vite
• Axios

Backend

• Node.js
• Express.js
• MongoDB
• Mongoose

Authentication

• JWT
• bcryptjs
• Google Identity Services
• GitHub OAuth
• Nodemailer
• Mailtrap

Development

• ESLint
• Prettier

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📂 Project Structure

.
├── client/
├── server/
├── assets/
├── README.md
└── .gitignore

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🚀 Getting Started

Clone the repository

git clone https://github.com/Beast18akash/mern-auth-system.git
cd mern-auth-system

Install dependencies

Frontend

cd client
npm install

Backend

cd server
npm install

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⚙️ Environment Variables

Create the following files.

Client

VITE_API_URL=http://localhost:5000
VITE_GOOGLE_CLIENT_ID=your_google_client_id

Server

PORT=5000

MONGO_URI=your_mongodb_uri

JWT_SECRET=your_jwt_secret

CLIENT_URL=http://localhost:5173

EMAIL_HOST=
EMAIL_PORT=
EMAIL_USER=
EMAIL_PASS=

GOOGLE_CLIENT_ID=

GITHUB_CLIENT_ID=
GITHUB_CLIENT_SECRET=
GITHUB_CALLBACK_URL=http://localhost:5000/api/auth/github/callback

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▶️ Running the Project

Start the backend

cd server
npm run dev

Start the frontend

cd client
npm run dev

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📸 Screenshots

Sign Up

Sign In

Forgot Password

Sign In with Google

Sign In with GitHub

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🏗️ Authentication Flow

User
   │
   ├──────────────────┬──────────────────┐
   │                  │                  │
   ▼                  ▼                  ▼
Local Login      Google Login      GitHub Login
   │                  │                  │
   └──────────────────┼──────────────────┘
                      ▼
          Authentication Service
                      │
                      ▼
           Account Linking Layer
                      │
                      ▼
           JWT Authentication
                      │
                      ▼
          HTTP-only Cookie Session
                      │
                      ▼
          Protected Application

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📦 Releases

Version	Description
v1.0.0	Initial stable authentication service
v1.1.0	GitHub OAuth & Multi-provider authentication

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🔮 Roadmap

• Email Verification
• Refresh Tokens
• Session Management
• User Profile
• Two-Factor Authentication (2FA)
• Role-Based Access Control (RBAC)

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🤝 Contributing

Contributions, suggestions, and improvements are welcome.

Feel free to fork the repository and submit a pull request.

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📄 License

This project is licensed under the MIT License.