Failed Request Monitoring and Alert System

A robust backend system for monitoring failed POST requests, tracking IP-based request patterns, and sending alerts when suspicious activity is detected.

🌟 Features

• Request Monitoring: Tracks failed POST requests due to invalid headers or incorrect access tokens
• IP Tracking: Monitors and logs requests from each IP address within configurable time windows
• Alert System: Sends email notifications when failed attempts exceed thresholds
• Metrics Collection: Stores and exposes detailed metrics for analysis
• Rate Limiting: Protects against excessive requests
• Scalable Architecture: Designed to handle high traffic volumes (~500 requests/second)

🔧 Tech Stack

• Backend: Node.js with Express
• Database: MongoDB
• Email: Gmail SMTP Server
• Logging: Winston Logger
• Security: Helmet middleware
• Testing: Jest

📋 Prerequisites

• Node.js (>=14.0.0)
• MongoDB
• Gmail account for sending alerts
• Git (for version control)

🚀 Getting Started

1. Clone and Install

# Clone the repository
git clone <repository-url>

# Navigate to project directory
cd API-Failure-Logger

# Install dependencies
npm install

2. Configuration

Create a .env file in the root directory:

NODE_ENV=development
PORT=3000
MONGODB_URI=mongodb+srv://<username>:<password>@<cluster>.mongodb.net/<database>
SMTP_USER=[email protected]
SMTP_PASS=your-gmail-app-password
ADMIN_EMAIL=[email protected]
ALERT_THRESHOLD=5
TIME_WINDOW_MINUTES=10
LOG_LEVEL=debug

3. Gmail Setup for Alerts

1. Go to Google Account Settings
2. Enable 2-Factor Authentication
3. Navigate to Security → App passwords
4. Generate new app password
5. Use the generated password in SMTP_PASS environment variable

4. Running the Application

# Development mode with auto-reload
npm run dev

# Production mode
npm start

📝 API Documentation

POST /api/submit

Main endpoint for request monitoring

Headers Required:

• Authorization: Bearer token
• Content-Type: Application type
• User-Agent: Client identifier

GET /api/metrics

Fetch general metrics with pagination and time range filtering

Query Parameters:

• timeRange: '1h', '24h', '7d', '30d' (default: '24h')
• page: Page number (default: 1)
• limit: Items per page (default: 10)

GET /api/metrics/:ip

Fetch metrics for specific IP address

Query Parameters:

• timeRange: Time window for metrics

GET /api/metrics/summary/statistics

Get summary statistics of failed requests

Query Parameters:

• timeRange: Time window for statistics

🧪 Testing

Running Tests

# Run all tests
npm test

# Watch mode
npm run test:watch

# Coverage report
npm run test:coverage

Manual Testing

Test invalid requests:

# Missing authentication
curl -X POST http://localhost:3000/api/submit

# Invalid token
curl -X POST http://localhost:3000/api/submit \
  -H "Authorization: Bearer invalid-token"

Test metrics:

# Get general metrics
curl http://localhost:3000/api/metrics

# Get IP-specific metrics
curl http://localhost:3000/api/metrics/127.0.0.1

📊 Monitoring & Debugging

• Logs: Check logs/ directory
  • error.log: Error-level logs
  • combined.log: All logs
• MongoDB: Monitor collections for failed requests
• Email Alerts: Check configured admin email

⚙️ Architecture

src/
├── app.js              # Application entry point
├── config/             # Configuration files
├── database/           # Database connection
├── middleware/         # Express middleware
├── models/            # MongoDB models
├── routes/            # API routes
├── services/          # Business logic
└── utils/             # Utility functions

🔐 Security Features

• Rate limiting
• Request validation
• Security headers (Helmet)
• Token validation
• IP tracking
• Alert system

⚡ Performance Optimizations

• MongoDB connection pooling
• Request compression
• Efficient indexing
• Cache implementation
• Rate limiting

🛠 Troubleshooting

Common issues and solutions:

1. MongoDB Connection Issues

   • Verify MONGODB_URI
   • Check network connectivity
   • Verify MongoDB service status

2. Email Alert Issues

   • Verify SMTP credentials
   • Check Gmail settings
   • Verify no rate limits

3. Rate Limiting

   • Check logs for blocked requests
   • Verify rate limit configuration

📈 Scaling Considerations

• Horizontal scaling capability
• Load balancer ready
• Database indexing
• Connection pooling
• Rate limiting by IP

🤝 Contributing

1. Fork the repository
2. Create feature branch
3. Commit changes
4. Push to branch
5. Create Pull Request

📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

👥 Support

For any issues, email [email protected] or create an issue in the repository.