Golancer

GoLancer is a lightweight, high-performance reverse proxy and load balancer written in Go. It is designed to be simple, configurable, and production-ready with clear separation of control plane and data plane, hot-reloadable configuration, structured logging, and graceful shutdown support.

Features (Completed so far)

• Reverse Proxy

  • Routes HTTP/HTTPS traffic to upstream services.
  • Path prefix and host-based routing.

• Load Balancing

  • Round-robin load balancing across multiple upstreams.

• Dynamic Config Management

  • Configuration defined via YAML.
  • Hot reload powered by Viper + fsnotify.
  • Immutable vs mutable config separation.

• Structured Logging

  • Append-only, file-based logger.
  • Async logging with mailbox pattern (non-blocking).

• Graceful Shutdown

  • Control plane manages shutdown signals.
  • Cleans up data plane, logger, and config watchers.

• TLS/HTTPS Support

  • Self-signed certs for local development.
  • Let’s Encrypt integration for production (planned).

Installation Guide

Clone this repo and run

go run ./cmd/golancer start --port 8080 --config config.yaml

Flags:

• --port or -p: Port to run Golancer. Default: 8080
• --config or -c: Config file path to listen. Default: config.yaml
• --useTLS: Use Golancer in TLS mode. Default: false
• --local: Set Golancer in local development mode. Default: false
• --logFile or -l: Log file path to write. Default: golancer.log

Configuration Guide

A sample config file looks similar to this

proxy:
  default_timeout: 5s
  max_idle_conns: 100
  idle_conn_timeout: 90s

routes:
  - name: api
    match:
      hosts: ["localhost:8080"]
      path_prefix: /api
    upstreams:
      - https://127.0.0.1:8081
      - https://127.0.0.1:8082
    lb: round_robin

Roadmap

• Rever Proxy (HTTP/HTTPS)
• Round Robin Load balancing
• Control plane and Data plane
• Hot reload on configuration changes
• Append-only file based logger
• More Load balancing strategies (least connection, hash)
• Metrics (Prometheus exporter)
• Middleware support
• Let's encrypt integration for automatic TLS
• Health checks for upstreams
• Circuit breakers + retries
• Graceful reloads without dropping in-flight requests

Contributing

Contributions, issues, and feature requests are welcome!
Please open a PR or file an issue.

License

MIT License © 2025 [Nanthakumaran Senthilnathan]