My Ruby on Rails application uses the following controller code to generate a sitemap.xml file:
class SitemapController < ApplicationController
layout nil
def index
headers['Content-Type'] = 'application/xml'
last_post = Post.last
if stale?(:etag => last_post, :last_modified => last_post.updated_at.utc)
respond_to do |format|
format.xml { @posts = Post.sitemap } # sitemap is a named scope
end
end
end
end
My understanding is that the stale?
method should ensure a HTTP 304 Not Modified response if the content hasn't changed. However, whenever I test this using curl or a web browser I always get an HTTP 200:
$ curl --head localhost:3000/sitemap.xml HTTP/1.1 200 OK Connection: close Date: Mon, 13 Apr 2009 15:50:00 GMT Last-Modified: Wed, 08 Apr 2009 16:52:07 GMT X-Runtime: 100 ETag: "5ff2ed60ddcdecf291e7191e1ad540f6" Cache-Control: private, max-age=0, must-revalidate Content-Type: application/xml; charset=utf-8 Content-Length: 29318
Am I using the stale?
method correctly? Is it even possible to test this locally?
Best Answer
it is likely that your Rails code is just fine but curl is not sending the If-Modified-Since header when you perform your test. From the curl docs: