Load Balancer Go 🚀

A high-performance HTTP load balancer built in Go with optional rate limiting and JWT authentication.

✨ Features

• 🔄 Load Balancing Algorithms

  • Round Robin
  • Least Connections

• 🛡️ Optional Security

  • JWT-based authentication (optional)
  • Rate limiting with token bucket algorithm (optional)
  • Per-client IP rate limiting

• 🏥 Health Monitoring

  • Automatic backend health checks
  • Real-time backend status monitoring

• ⚡ Performance

  • HTTP reverse proxy
  • Concurrent request handling
  • Configurable middleware

📦 Installation

From Source

git clone https://github.com/Rx-11/load-balancer-go.git
cd load-balancer-go
go mod tidy
go build -o load-balancer main.go

🚀 Quick Start

1. Create Configuration

Create a config.json file:

{
    "port": "8080",
    "jwt_secret": "",
    "load_balancer": {
        "algorithm": "round_robin"
    },
    "rate_limit": {
        "enable": false,
        "requests_per_second": 100,
        "burst_size": 50
    },
    "backends": [
        {
            "id": "backend1",
            "url": "http://localhost:8081",
            "health": true
        },
        {
            "id": "backend2",
            "url": "http://localhost:8082",
            "health": true
        }
    ]
}

2. Run Load Balancer

go run main.go

3. Test It

# Basic request
curl http://localhost:8080/

# Health check
curl http://localhost:8080/health

⚙️ Configuration

Basic Settings

Field	Description	Example
port	Server port	"8080"
jwt_secret	JWT secret (leave empty to disable auth)	""

Load Balancer

"load_balancer": {
    "algorithm": "round_robin"
}

Available algorithms:

• round_robin - Distributes requests evenly
• least_connections - Routes to backend with fewest connections

Rate Limiting

"rate_limit": {
    "enable": true,
    "requests_per_second": 100,
    "burst_size": 50
}

• Set enable: false to disable rate limiting
• requests_per_second - Sustained request rate
• burst_size - Maximum burst capacity

Backends

"backends": [
    {
        "id": "backend1",
        "url": "http://localhost:8081",
        "health": true
    }
]

🔐 Authentication

When jwt_secret is set, all requests except /health require a JWT token:

curl -H "Authorization: Bearer YOUR_JWT_TOKEN" http://localhost:8080/

🏥 Health Checks

The load balancer sends GET requests to /health on each backend every 30 seconds. Backends should return HTTP 200 for healthy status.

Available endpoints:

• GET /health - Load balancer health status

🛠️ Project Structure

load-balancer-go/
├── main.go                 # Application entry point
├── config/
│   └── config.go          # Configuration management
├── loadbalancer/
│   ├── roundrobin.go      # Round robin algorithm
│   ├── leastconn.go       # Least connections algorithm
│   └── balancer.go        # Load balancer interface
├── middleware/
│   ├── auth.go            # JWT authentication
│   └── ratelimiter.go     # Rate limiting
├── proxy/
│   └── http.go            # HTTP reverse proxy
└── health/
    └── checker.go         # Health monitoring

📋 Use Cases

• API Gateway - Route requests with optional authentication
• Web Application Load Balancer - Distribute traffic across multiple servers
• Development Environment - Simple load balancing for local testing

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test your changes
5. Submit a pull request

📄 License

This project is licensed under the MIT License.

---

Made with ❤️ in Go