Dashboard Backend

Real-time cryptocurrency price streaming server built with Express.js and Socket.IO

🎯 Features

• ✅ Real-time cryptocurrency prices via WebSocket
• ✅ CoinGecko API integration (free, no API key needed)
• ✅ Automatic data refresh every 5 seconds
• ✅ CORS enabled for cross-origin requests
• ✅ Connection tracking and client count broadcasting
• ✅ Graceful error handling
• ✅ Automatic reconnection support

🛠 Tech Stack

• Framework: Express.js v4.18+
• Real-time: Socket.IO v4.5+
• HTTP Client: Axios v1.5+
• Environment: Dotenv v16+
• CORS: CORS middleware v2.8+

📋 Prerequisites

• Node.js v16.0.0 or higher
• npm v8.0.0 or higher

🚀 Quick Start

1. Installation

npm install

2. Environment Setup

Create a .env file:

PORT=5000
NODE_ENV=development
CORS_ORIGIN=http://localhost:3000

3. Start Development Server

npm run dev

Server will run on http://localhost:5000

4. Start Production Server

npm start

📡 WebSocket Events

Client → Server

requestData

• Payload: { dataType: 'crypto' }
• Description: Client requests crypto data

Server → Client

data

• Payload: Real-time cryptocurrency data
• Emitted: Every 5 seconds

clientCount

• Payload: { count: number }
• Description: Total connected clients

error

• Payload: { message: string, details: string }
• Description: Error occurred

📊 Data Response Format

{
  "type": "crypto",
  "timestamp": "2025-10-28T12:00:00.000Z",
  "prices": {
    "bitcoin": {
      "usd": 42500.50,
      "usd_market_cap": 850000000000,
      "usd_24h_vol": 25000000000,
      "usd_24h_change": 2.5
    },
    "ethereum": {
      "usd": 2300.75,
      "usd_market_cap": 280000000000,
      "usd_24h_vol": 15000000000,
      "usd_24h_change": 1.8
    }
  }
}

🔄 Supported Cryptocurrencies

• Bitcoin (BTC)
• Ethereum (ETH)
• Cardano (ADA)
• Solana (SOL)
• Ripple (XRP)

🔒 Security

• Environment variables for sensitive data
• CORS restrictions configurable
• Input validation on events
• Error messages sanitized
• No sensitive data exposed

🐛 Debugging

Enable Verbose Logging

The server logs all important events:

• Client connections/disconnections
• Data requests
• API calls
• Errors

Check console output for troubleshooting

Common Issues

Port Already in Use

# Mac/Linux
lsof -i :5000

# Windows
netstat -ano | findstr :5000

CORS Errors

• Check CORS_ORIGIN in .env matches frontend URL
• Verify frontend is running on http://localhost:3000

API Not Responding

• Check internet connection
• CoinGecko API may be rate-limited
• Server will auto-retry

📈 Performance

• Lightweight and fast
• Handles multiple concurrent connections
• Efficient data updates (5-second intervals)
• Minimal bandwidth usage

🚀 Deployment Ready

Tested and ready for deployment on:

• Railway.app ✅
• Render.com ✅
• Heroku ✅
• DigitalOcean ✅
• AWS ✅

📝 API Health Check

curl http://localhost:5000/health

Response:

{
  "status": "OK",
  "message": "Server is running",
  "timestamp": "2025-10-28T12:00:00.000Z"
}

📄 License

ISC

👤 Author

CloudForge Dev Team

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Status: Production Ready Last Updated: 2025-10-28