JustChat - Professional Real-Time Chat Application

A high-performance, secure, and scalable chat application built with the MERN stack and Socket.io.

🚀 Key Features

• Real-time Messaging: Low-latency communication via Socket.io.
• Secure Authentication: JWT-based auth with HTTP-only cookies and bcrypt hashing.
• Robust Architecture: Modular service-oriented architecture with centralized error handling.
• File Uploads: Integrated Cloudinary support for profile pictures and message attachments.
• Responsive Design: Polished UI using Tailwind CSS and DaisyUI.
• Performance Optimized: Lazy loading, code splitting, and efficient MongoDB indexing.

🛠 Tech Stack

• Frontend: React 19, Vite, Zustand, Tailwind CSS, DaisyUI, Lucide React.
• Backend: Node.js, Express 5, MongoDB (Mongoose), Socket.io, Pino (Logging).
• Security: Helmet, Express Rate Limit, CSRF protection via SameSite cookies.
• DevOps: Docker, Docker Compose.

📁 Project Structure

chatApp/
├── backend/
│   ├── src/
│   │   ├── config.js         # Centralized environment configuration
│   │   ├── controllers/      # HTTP request handlers (thin controllers)
│   │   ├── services/         # Business logic (service layer)
│   │   ├── models/           # Mongoose schemas
│   │   ├── middleware/       # Auth, validation, and error middlewares
│   │   └── lib/util/         # Standardized utilities (logger, error, etc.)
│   └── bootstrap.js          # App entry point with env setup
├── frontend/
│   ├── src/
│   │   ├── components/       # Reusable UI components & ErrorBoundary
│   │   ├── pages/            # View components (lazy loaded)
│   │   ├── store/            # Zustand state management
│   │   └── lib/              # Axios instance and utils
└── Dockerfile                # Production-ready multi-stage build

🚦 Getting Started

Prerequisites

• Node.js 20+
• MongoDB instance
• Cloudinary Account

Local Development

1. Clone the repository:

   git clone https://github.com/shubhambhattacharya-dev/chatApp.git
   cd chatApp

2. Backend Setup:

   cd backend
   cp .env.example .env # Fill in your credentials
   npm install
   npm run dev

3. Frontend Setup:

   cd frontend
   npm install
   npm run dev

Docker Deployment

docker-compose up --build

🛡 Security & Best Practices

• Service Layer: Decoupled business logic from controllers for better testability.
• Global Error Handling: Consistent API responses for operational and programming errors.
• Environment Validation: Fail-fast mechanism if required configuration is missing.
• Logging: Structured logging using Pino for production-grade observability.
• Error Boundaries: Prevents UI crashes from propagating.

📄 License

ISC