Rack::Preview is a simple piece of Rack middleware to let you serve a different response to requests made as part of Safari's Top Sites and Opera's Speed Dial thumbnail previews, by hooking into the X-Purpose: preview HTTP header.
To see the effect, check Martin Sutherland's write-up for Safari. Opera's dev blog also has more.
To install from RubyGems:
gem install rack-preview
To get the source:
git clone https://github.com/aprescott/rack-preview.git
require "rack/preview"
Rack::Server.start(app: Rack::Builder.app do
use Rack::Preview, %Q{<h1 style="font-size: 10em;">Welcome to the preview!</h1>}
run lambda { |env| [200, { "Content-Type" => "text/html" }, ["Hello world!"]] }
end)# Regular response.
$ curl http://localhost:8080/
Hello world!
# Responses to requests with X-Purpose
# from the relevant browsers.
$ curl -H "X-Purpose: preview" --user-agent "Safari" http://localhost:8080/
<h1 style="font-size: 10em;">Welcome to the preview!</h1>- Fork it
- Make a new feature branch:
git checkout -b some-new-thing master - Hack away and write tests that pass
- Pull request