May 18 2009

Rack::CacheHeaders code

A few months ago I wrote about a possible method for centrally configuring HTTP cache headers in Rack based web applications which I called Rack::CacheHeaders. This is useful if your application's architecture involves tools like Squid or Varnish, or if you are generally interested in harvesting the numerous advantages of HTTP caching for your web application.

The code has evolved a bit since and proven useful in a number of production systems. I created a gist of Rack::CacheHeaders in case someone else finds it handy. The tool is not exhaustive in terms of policies as found in the HTTP specs, it's a collection of the ones we needed in the projects it's been used so far. Consider adding ones you need to the gist to make the code more complete and widely useful.

Rack::CacheHeaders allows configuring HTTP cache policy response headers based on request URI patterns. For example, to set the Cache-Control: max-age header for a /guitars/:id resource to one hour:

Rack::CacheHeaders.configure do |cache|
  cache.max_age(/^\/guitars\/d+$/, 3600)

Download/develop Rack::CacheHeaders