Rack 0.1, a modular Ruby webserver interface


Today I’m proud to release Rack 0.1.

= Rack, a modular Ruby webserver interface

Rack provides a minimal, modular and adaptable interface for developing
web applications in Ruby. By wrapping HTTP requests and responses in
the simplest way possible, it unifies and distills the API for web
servers, web frameworks, and software in between (the so-called
middleware) into a single method call.

The exact details of this are described in the Rack specification,
which all Rack applications should conform to.

== Supported web servers

The included handlers connect all kinds of web servers to Rack:

  • Mongrel
  • WEBrick
  • FCGI
  • CGI

Any valid Rack app will run the same on all these handlers, without
changing anything.

== Supported web frameworks

The included adapters connect Rack with existing Ruby web frameworks:

  • Camping
  • Rails (alpha)
  • more to come soon, …

These frameworks include Rack adapters in their distributions:

  • Ramaze
  • Maveric
  • Racktools::SimpleApplication

== Available middleware

Between the server and the framework, Rack can be customized to your
applications needs using middleware, for example:

  • Rack::URLMap, to route to multiple applications inside the same
  • Rack::CommonLogger, for creating Apache-style logfiles.
  • Rack::ShowException, for catching unhandled exceptions and
    presenting them in a nice and helpful way with clickable backtrace.
  • Rack::File, for serving static files.

All these components use the same interface, which is described in
detail in the Rack specification. You can choose to use them exactly
in the way you want.

== Convenience

If you want to develop outside of existing frameworks, implement your
own ones, or develop middleware, Rack provides many helpers to create
Rack applications quickly and without doing the same web stuff all

  • Rack::Request, which also provides query string parsing and
    multipart handling.
  • Rack::Response, for convenient generation of HTTP replies and
    cookie handling.
  • Rack::MockRequest and Rack::MockResponse for efficient and quick
    testing of Rack application without real HTTP round-trips.

== rackup

rackup is a useful tool for running Rack applications, which uses the
Rack::Builder DSL to configure middleware and build up applications

rackup automatically figures out the environment it is run in, and
runs your application as FastCGI, CGI, or standalone with Mongrel or
WEBrick—all from the same configuration.

== Where can I get it?

You can download Rack 0.1 at


Alternatively, you can checkout from the development repository with:

       darcs get http://chneukirchen.org/repos/rack

(Patches using “darcs send” are most welcome.)

== Installing with RubyGems

A Gem of Rack is available. You can install it with:

gem install rack

I also provide a local mirror of the gems (and development snapshots)
at my site:

gem install rack --source http://chneukirchen.org/releases/gems

== History

  • March 3rd, 2007: First public release 0.1.

== Contact

Please mail bugs, suggestions and patches to
mailto:[email protected].

Darcs repository (“darcs send” is welcome for patches):

You are also welcome to join the #rack channel on irc.freenode.net.

== Thanks to

  • Michael F., for helpful discussion.
  • Christoffer S., for the Rails adapter.
  • Armin Ronacher, for the logo and racktools.
  • Marcus Rückert, for help with configuring and debugging lighttpd.
  • The WSGI team for the well-done and documented work they’ve done and
    Rack builds up on.

== Copyright

Copyright (C) 2007 Christian N.

Rack is freely distributable under the terms of an MIT-style license.

== Links

Rack:: http://rack.rubyforge.org/
Rack’s Rubyforge project:: http://rubyforge.org/projects/rack

Camping:: http://camping.rubyforge.org/
Ramaze:: http://ramaze.rubyforge.org/
Maveric:: http://maveric.rubyforge.org/
racktools:: http://lucumr.pocoo.org/trac/repos/racktools/

Christian N.:: http://chneukirchen.org/

Happy hacking and have a nice day,
Christian N.

79b46158b7b30adcd7a9148cc7ed4305 rack-0.1.0.tar.gz
61a51b2f609833f4e0c11213a0070721 rack-0.1.0.gem

On 3/3/07, Christian N. [email protected] wrote:


Today I’m proud to release Rack 0.1.

= Rack, a modular Ruby webserver interface

Nice one Christian!


Hello Christian,

Rack looks nice. When the projects gets more mature I will consider
using it for the Nitro Web Framework as well.
At the moment, I am rewriting Nitro internals almost from scratch,
trying to simplify the code as much as possible. Using Rack may fit
well in this strategy.

George M.