Chatties - Real-Time Chat App

Chatties is a scalable and feature-rich real-time chat application built with PERN Stack (PostgreSQL, Express, React, Node.js) and Drizzle ORM. It leverages Redis Pub/Sub and Kafka to ensure smooth and efficient real-time messaging across multiple instances. The app includes essential chat functionalities such as online status, message alerts, group chats, file uploads, and a fully responsive UI with light/dark mode.

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🚀 Features

🔹 Real-Time Messaging

• Instant messaging using WebSockets (Socket.io)
• Read receipts and delivery statuses
• Typing indicators

🔹 User & Group Chats

• One-on-one private chats
• Group conversations with role-based permissions
• Pinned messages and chat muting

🔹 Scalability & Performance

• Redis Pub/Sub for multi-instance synchronization
• Kafka Integration for high-throughput message processing
• Drizzle ORM for efficient database handling
• Optimized queries for high-speed data retrieval

🔹 Online Presence & Notifications

• Live user status (Online/Offline)
• Real-time notifications for messages

🔹 Multimedia & File Sharing

• Image, video, and document uploads
• Drag & drop support for easy file sharing

🔹 UI & Accessibility

• Fully responsive and mobile-friendly design
• Light/Dark mode with theme persistence
• Keyboard accessibility for improved usability

🔹 Security & Authentication

• JWT-based authentication for secure login
• OAuth support (Google, GitHub, etc.)
• End-to-end encryption for private messages (future feature)

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🛠️ Tech Stack

Frontend:

• React (Vite/Next.js optional)
• Tailwind CSS for styling
• Redux Toolkit for state management

Backend:

• Node.js + Express.js
• PostgreSQL (Drizzle ORM for database management)
• Redis for caching and Pub/Sub messaging
• Kafka for message queue management
• Socket.io for real-time communication

Deployment & DevOps:

• Vercel for frontend hosting
• NeonDB for database hosting
• CI/CD integration with GitHub Actions -render for backend

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🔧 Kafka-Based Consumer Implementation

🔹 Unified Kafka Consumer for Chat & Group Messages

Chatties now utilizes a single Kafka consumer that subscribes to both chat-messages and group-messages topics, ensuring efficient processing without redundant subscriptions. The consumer:

• Listens to messages from both chat and group topics.
• Processes messages and updates the database accordingly.
• Publishes updates to Redis for real-time UI updates.
• Efficiently increments unread message count for other users.

🔹 Benefits of Kafka Integration

• Scalability: Handles large volumes of messages seamlessly.
• Fault Tolerance: Ensures messages are processed even if an instance fails.
• Decoupled Architecture: Allows independent scaling of consumers and producers.
• Optimized Database Writes: Reduces redundant queries, improving performance.

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🔧 Installation & Setup

1. Clone the repository:

   git clone https://github.com/your-username/chatties.git
   cd chatties

2. Install dependencies:

   npm install  # or yarn install

3. Set up environment variables: (Create a .env file and configure your variables)

   DATABASE_URL=your_postgresql_url
   REDIS_URL=your_redis_url
   KAFKA_BROKER=your_kafka_broker_url
   JWT_SECRET=your_jwt_secret

4. Run the backend server:

   cd server
   npm run dev

5. Start the Kafka consumer:

   npm run consume

6. Start the frontend app:

   cd client
   npm run dev

7. Access the application: Open http://localhost:3000 in your browser.

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📌 Future Scope

🔹 Enhanced Real-Time Communication

• End-to-End Encryption for private chats to enhance security.
• Video & Voice Calls using WebRTC for real-time audio/video communication.

🔹 Improved User Experience

• AI-based smart reply suggestions.
• Push Notifications for web & mobile alerts.

🔹 Advanced Analytics & Moderation

• Admin Dashboard for chat moderation and user management.
• Sentiment Analysis for content moderation.
• Message Auditing for compliance and security.

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⚡ Happy Chatting with Chatties! 🚀