= Rewritten 

Rewritten is a lookup-based rewriting engine that rewrites requested
URLs on the fly. The URL manipulations depend on translations found in
a redis database.

If a matching translation is found, the result of a request is either a
redirection or a modification of path and request parameters. For URLs
without translation entries the request is left unmodified.

Rewritten takes larges parts from the Resque codebase (which rocks). The
gem is compromised of four parts:

1. A Ruby library for creating, modifying and querying translations
2. A Sinatra app for displaying and managing translations
3. A Rack app for rewriting and redirecting request (Rack::Rewritten::Url)
4. A Rack app for substituting URLs in HTML pages with their current translation (Rack::Rewritten::Html)
5. A Rack app for recording successful request (Rack::Rewritten::Record)


== New Relic Notice

There seem to be unresolved issues when Rack::Rewritten::Html is used
in conjunction with the New Relic gem (being a rack app as well).
Unfortunately the only workaround so far is either disabling New Relic
or Rack::Rewritten::Html (pointers in the right debugging direction or
pull requests are welcome).


== Overview

The Rewritten library allows you to create new URL translations and     
then query for the current "trade language" of an URL.                  

    Rewritten.add_translation('/apple-computer/newton', '/products/4e4d3c6a1d41c811e8000009')
    Rewritten.add_translation('/apple/ipad', '/products/4e4d3c6a1d41c811e8000009')
    Rewritten.get_current_translation('/products/4e4d3c6a1d41c811e8000009')         # => "/apple/ipad"

Translations are removed in a similar fashion.

    Rewritten.remove_translation('/apple-computer/newton', '/products/4e4d3c6a1d41c811e8000009')


== Usage in your Rack stack

To take full advantage of the engine you would use both, the URL and
HTML, rack apps as follows:

    use Rack::Rewritten::Url
    use Rack::Rewritten::Html
    run Your::App

This way the URL rewriting and generation is stays decoupled from your
app. For a Rails app, for instance, you wouldn't need to mess with your
<tt>routes.rb</tt> or path helpers when dealing with custom URLs.


== The Front End

Rewritten comes with a Sinatra-based front end for dislaying and
managing your URL translations (in the familiar Resque layout).

[IMAGE]


=== Standalone

Running Rewritten as a gem in standalone mode is easy:

    $ rewritten-web 

It's based on Vegas, a thin layer around rackup, and as such configurable as well:

    $ rewritten-web -p 8282


=== Rack::URLMap

To load Rewritten on a subpath alongside other apps you can make use of URLMap:

run Rack::URLMap.new \
    "/"       => Your::App.new,
    "/resque" => Rewritten::Server.new
    
Check lib/test.ru for a functional example.