🚀 Advanced Go Load Balancer

A high-performance, feature-rich HTTP/S load balancer built from scratch in Go

Educational • Modular • Production-Ready

📑 Table of Contents

• 🚀 Advanced Go Load Balancer
  • 📑 Table of Contents
  • ✨ Overview
  • 🎯 Features
    • 🔄 Load Balancing
    • 🏥 Health Monitoring
    • 🛣️ Advanced Routing
    • 🛡️ Policy Enforcement
    • 🔧 Additional Features
  • 📁 Project Structure
  • 🚀 Quick Start
    • Prerequisites
    • Installation
    • Running
  • ⚙️ Configuration
    • Configuration Example
  • 🏗️ Architecture
    • Design Principles
    • Core Components
  • 🔍 Observability
    • Logging
    • Metrics
    • Tracing
  • 🎓 Lessons Learned & Skills Demonstrated
  • 🤝 Contributing
  • 📊 Roadmap
  • 📄 License

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✨ Overview

⚠️ Beta Release: This project is currently in beta and actively under development. Features and APIs may evolve.

This project showcases an advanced HTTP/S load balancer implementation in Go, designed as both an educational resource and a practical networking infrastructure component. Built with modularity and extensibility in mind, it demonstrates core concepts of distributed systems, load balancing, and network programming.

🎯 Features

🔄 Load Balancing Multiple Algorithms: Round Robin, Least Connections, Weighted Smart Distribution: Intelligent traffic routing Backend Pool Management: Organized backend grouping 🏥 Health Monitoring Active Health Checks: Continuous backend monitoring Pluggable Probes: HTTP, TCP health check support Automatic Failover: Seamless backend switching

🛣️ Advanced Routing Multi-Factor Routing: Host, path, method, headers Flexible Rules: Complex routing configurations Dynamic Updates: Runtime route modifications 🛡️ Policy Enforcement Rate Limiting: Request throttling and control Header Transformation: Request/response modification IP Access Control: Whitelist/blacklist support

🔧 Additional Features

• HTTP/S Reverse Proxying with high performance
• Graceful Shutdown for clean terminations
• Observability Integration with logging, metrics, and tracing
• Modular Architecture for easy extension

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📁 Project Structure

The project follows the standard Go project layout:

go-loadbalancer/
├── 📄 cmd/go-lb/                # Application entry point
│   └── main.go                  # Main application file
├── 🌐 api/                      # API definitions
│   └── http/v1/                 # HTTP API version 1
├── ⚙️  configs/                  # Configuration files and templates
│   ├── config.go                # Configuration structures
│   └── loader.go                # Configuration loading logic
├── 🔒 internal/                  # Internal business logic
│   ├── app/                     # Application initialization
│   ├── admin/                   # Admin interface
│   ├── backend/                 # Backend server management
│   ├── healthcheck/             # Health checking system
│   ├── logging/                 # Structured logging
│   ├── middleware/              # HTTP middleware
│   ├── monitoring/              # Metrics and monitoring
│   ├── serverpool/              # Backend pools & algorithms
│   ├── routing/                 # Request routing engine
│   ├── policy/                  # Policy enforcement
│   ├── tracing/                 # Distributed tracing
│   └── handler/                 # Core request handlers
├── 📦 pkg/                      # Reusable utilities
├── 🧪 test/                     # Additional test applications
├── 🔧 scripts/                  # Scripts for various tasks
├── 🚢 deployments/              # Deployment configurations
│   └── docker/                  # Docker-related files
├── 📊 tools/                    # Tools and utilities
│   └── k6/                      # K6 load testing scripts
└── 📚 docs/                     # Documentation files

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🚀 Quick Start

Prerequisites

• Go 1.23+ installed on your system
• Backend services to load balance (for testing)

Installation

# Clone the repository
git clone https://github.com/rixtrayker/go-loadbalancer.git

# Navigate to project directory
cd go-loadbalancer

# Build the project
go build -o build/go-lb ./cmd/go-lb

Running

# Start with default configuration
./build/go-lb

# Or specify a config file
./build/go-lb --config configs/config.yml

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⚙️ Configuration

The load balancer uses a flexible configuration system supporting:

• 🎯 Listener Settings: Address, port, TLS configuration
• 🏊 Backend Pools: Server groups with load balancing algorithms
• 💓 Health Checks: Monitoring intervals, timeouts, and probe types
• 🛣️ Routing Rules: Complex request matching and forwarding
• 📋 Policies: Rate limiting, transformations, and access control
• 📊 Monitoring: Logging, metrics, and tracing configuration

Configuration Example

server:
  address: ":8080"
  
backend_pools:
  - name: "web-servers"
    algorithm: "round_robin"
    backends:
      - url: "http://localhost:3001"
        weight: 1
      - url: "http://localhost:3002"
        weight: 2
    health_check:
      path: "/health"
      interval: "30s"
      timeout: "5s"

routing_rules:
  - match:
      host: "example.com"
      path: "/api/*"
    target_pool: "web-servers"
    policies:
      - rate_limit: "100/minute"

monitoring:
  prometheus:
    enabled: true
    path: "/metrics"
    port: 9090
  tracing:
    enabled: true
    service_name: "go-loadbalancer"
    endpoint: "localhost:4317"

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🏗️ Architecture

Design Principles

• 🔧 Modularity: Clean separation of concerns
• 🔌 Extensibility: Plugin-based architecture
• ⚡ Performance: Optimized for high throughput
• 🛡️ Reliability: Robust error handling and recovery

Core Components

Component	Purpose
Router	Intelligent request routing and matching
Server Pool	Backend management and load balancing
Health Checker	Continuous backend monitoring
Policy Engine	Request/response transformation and control
Admin Interface	Runtime configuration and monitoring

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🔍 Observability

The load balancer includes comprehensive observability features:

Logging

• Structured JSON logging with zap
• Configurable log levels and formats
• Trace context correlation

Metrics

• Prometheus metrics for all components
• Request/response metrics
• Backend health and performance metrics
• System resource usage

Tracing

• OpenTelemetry integration
• Distributed tracing support
• Trace context propagation
• Span attributes for detailed analysis

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🎓 Lessons Learned & Skills Demonstrated

This project serves as an excellent learning resource, demonstrating several important concepts and best practices in Go development:

• Standard Go project layout
• Modular architecture with clean interfaces
• Effective use of middleware patterns
• Comprehensive observability implementation
• Advanced configuration management
• Multiple load balancing algorithms
• Policy-based request handling

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🤝 Contributing

We welcome contributions! See the Contributing Guide for more information.

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📊 Roadmap

• gRPC Load Balancing: Support for gRPC protocols
• Docker Integration: Containerized deployment
• Kubernetes Support: Native K8s integration
• WebSocket Proxying: Real-time connection support
• Circuit Breaker: Fault tolerance patterns

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📄 License

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

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Made with ❤️ by rixtrayker

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