Cache Warmer

A Go application that warms Varnish cache by making HTTP requests to predefined URLs.

Features

• Concurrent URL warming with configurable worker pool
• Retry mechanism with exponential backoff
• Environment variable configuration
• Docker support
• Kubernetes deployment ready
• Non-root container execution for security

Configuration

Set the following environment variable:

• VARNISH_BASE_URL: Base URL of your Varnish server (required)
• GOMAXPROCS: Maximum number of OS threads (optional, default: 2)
• CACHE_URLS: Comma-separated list of URLs to warm (optional)
  • Example: "/,/customer/account,/sofas.html,/catalog,/checkout"
  • If not provided, uses default URLs: /, /customer/account
• HOST_HEADER: optional, Host header submitted with the request
• AUTHORIZATION_HEADER: optional, Authorization header submitted with the request
  • Example: "Basic dXNlcm5hbWU6cGFzc3dvcmQ=" (for Basic authentication with base64 encoded "username:password")
  • Example: "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..." (for JWT token authentication)

Usage

Local Development