🔔 Real-Time Notification System

A production-ready backend system to send real-time push notifications using Node.js, Socket.IO, Redis, BullMQ, and PostgreSQL. It supports JWT-based authentication, device-wise refresh token management, and secure token rotation.

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📦 Tech Stack

• Node.js (Express)
• TypeScript
• Socket.IO for real-time communication
• Redis for Pub/Sub
• BullMQ for job queues
• MySQL with Prisma ORM
• Swagger for API docs
• JWT with Refresh Token Rotation
• Docker for containerization

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🧠 Features

• ✅ Real-time notification delivery using WebSocket
• ✅ BullMQ + Redis for background job processing
• ✅ Refresh token rotation with device session tracking
• ✅ Secure and scalable architecture
• ✅ Swagger UI for API testing
• ✅ PostgreSQL-based DB design
• ✅ Admin queue dashboard with authentication
• ✅ Socket room-based architecture for user isolation

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📂 Project structure

• dist
• node_modules
• prisma
• src
• -> assets
• -> config
• -> controllers
• -> dtos
• -> middleware
• -> public
• -> queues
• -> routes
• -> scripts
• -> services
• -> types
• -> utils
• -> workers
• -> ws
• -> index.ts
• -> loadEnv.ts
• .dockerignore
• .env
• .env.development
• .env.production
• .gitignore
• Dockerfile
• package-lock.json
• package.json
• readme.md
• tsconfig.json

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🖼️ High-Level Architecture

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🖼️ HLD - 2

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🧱 Database Schema

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🔐 Token Lifecycle Flow (JWT + Refresh Token)

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🔌 API Documentation

Swagger UI available at:

https://real-time-notification-system-production.up.railway.app/api-docs/

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🔐 Bull Dashboard (For analyzing message queue)

Dashboard available at:

https://real-time-notification-system-production.up.railway.app/admin/queues/

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🚀 Local Development Setup

# 1. Clone repo
git clone https://github.com/Jayakrishnan-mk/real-time-notification-system

# 2. Install dependencies
npm install

# 3. Start Redis & Postgres via Docker (if not already running)

# 4. Setup env
cp .env.development .env

# 5. Run migrations
npx prisma migrate dev

# 6. Start dev server
npm run dev

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🐳 Running with Docker (Production Build)

Build and run using Docker:

# 1. Build Docker image
docker build -t realtime-notify .

# 2. Run container
docker run -d -p 3000:3000 --env-file .env.production realtime-notify
Or if you're using Docker Compose:

bash
Copy
Edit
docker-compose up --build
Make sure your .env.production is properly set up with:

DATABASE_URL

REDIS_URL

JWT_SECRET

other required variables...

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🧪 Testing the Notification Flow

# You can test real-time notifications by:
- Logging in to get access/refresh tokens
- Opening WebSocket connection with userId
- Hitting /api/notifications to simulate push

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🌐 Deployment

Deployed on:

• Railway (Production)

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🤝 Contributing

PRs and suggestions welcome! 🙌

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📄 License

MIT