Auth Service (Express.js + MongoDB + Google OAuth)

This is a secure authentication microservice built using Express.js, MongoDB, Mongoose, and Passport.js with Google OAuth 2.0 support. It supports:

• User registration & login with email/password
• Login using Google account
• JWT-based authentication
• Role-based access control (admin, student, instructor)

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Features

• Register with email & strong password
• Login with email/password
• Login with Google using Passport.js
• Role-based access (e.g. admin only routes)
• JWT token issued on successful login
• Secured endpoints (e.g. /protected, /admin)
• Docker support
• CI pipeline via GitHub Actions

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Project Structure

.
├── config/
│   └── db.js                # MongoDB connection logic
├── controllers/
│   ├── Login.js             # Login controller (JWT)
│   ├── Register.js          # Registration controller
│   ├── Profile.js           # User profile (get/update)
│   └── passport.js          # Passport Google OAuth strategy
├── models/
│   └── User.js              # Mongoose User schema/model
├── src/
│   ├── middleware/
│   │   └── auth.js          # JWT authentication & role authorization
│   ├── routes/
│   │   └── route.js         # All API routes
│   └── server.js            # Express app entry point
├── utils/
│   └── response.js          # Helper for sending responses
├── DockerFile               # Docker build instructions
├── package.json             # Project dependencies & scripts
├── .gitignore               # Ignores .env and other files
└── .env                     # Environment variables (not committed)

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Environment Variables

Create a .env file in the root with:

PORT=5000
MONGO_URI=your_mongodb_connection_string
JWT_SECRET=your_jwt_secret
GOOGLE_CLIENT_ID=your_google_client_id
GOOGLE_CLIENT_SECRET=your_google_client_secret
GOOGLE_CALLBACK_URL=http://localhost:5000/auth/google/callback
NODE_ENV=development

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API Endpoints

Auth & User

• POST /register — Register a new user (name, email, password, phone)
• POST /login — Login with email & password (returns JWT)
• GET /auth/google — Start Google OAuth login
• GET /auth/google/callback — Google OAuth callback

Profile

• GET /profile — Get current user's profile (JWT required)
• PUT /profile — Update name/phone (JWT required)

Protected & Role-based

• GET /protected — Any authenticated user (JWT required)
• GET /admin — Only admin users (JWT required)

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Security

• Passwords are hashed with bcryptjs
• JWT tokens for stateless authentication
• Role-based access control middleware
• Google OAuth 2.0 via Passport.js

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Docker

Build and run with Docker:

docker build -t auth-service .
docker run -p 5000:5000 --env-file .env auth-service

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Scripts

• npm run dev — Start server with nodemon (development)

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Dependencies

• express, mongoose, dotenv, bcryptjs, jsonwebtoken, cors
• passport, passport-google-oauth20

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Notes

• Make sure to set up your Google OAuth credentials in the Google Cloud Console.
• The .env file is ignored by git for security.
• Replace your-production-domain.com in CORS settings for production.