Magic Incoming URL is a piece of rack middleware that redirects a URL to another one - but only when it's not a local link.

It's not designed to prevent hot-linking - it's designed for sites that respond to multiple domains, where different domains should lead to different landing pages.

e.g. You run Simon's Shoes and have two domains: simons-shoes.net and simons-boots.net. They both point to the same site, but you want customers who enter the simons-boots.net URL to start off looking at boots.

So entering:

http://www.simons-shoes.net goes to http://www.simons-shoes.net/

But entering:

http://www.simons-boots.net goes to http://www.simons-boots.net/boots

Rack::MagicIncomingUrl allows this to be easily configured:

require 'rack/magic-incoming-url'

map '/' do
  use Rack::MagicIncomingUrl, { 'www.simons-boots.net' => { '/' => 'http://www.simons-boots.net/boots' } }
  run MyWebApp
end

gem install rack-magic-incoming-url

or add

gem 'rack-magic-incoming-url'

to your Gemfile.

(c) Geoff Youngs, 2013

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