= Mongrel:  Simple Fast Mostly Ruby Web Server

Mongrel is a small library that provides a very fast HTTP 1.1 server for Ruby
web applications.  It is not particular to any framework, and is intended to
be just enough to get a web application running behind a more complete and robust
web server.

What makes Mongrel so fast is the careful use of a C extension to provide fast
HTTP 1.1 protocol parsing and fast URI lookup.  This combination makes the server
scream without too many portability issues.

== Status

The 0.3 release is the first official release to start supporting Ruby on Rails
and to have a more complete DirHandler for serving directories of files.   This release
is actually closer to a full functioning web server than the previous releases.

The Rails support is pretty rough right now, but check out the bin/mongrel_rails file,
which should be installed into your PATH if you use a gem.  You should be able to
do the following to run your Rails applications:

  > cd myrailsapp
  > mongrel_rails 0.0.0.0 3000

And then hit http://localhost:3000/ to see your app.  One thing is that if you have
a public/index.html file then you'll get that served instead of your Rails application.

People with the daemons gem installed will see that mongrel_rails will go into the
background.  You can kill it with:

  > kill -TERM `cat log/mongrel-3000.pid`

Where "3000" is whatever port you told it to listen on when you ran it.

The file serving is still a little rough and the redirects might not work well, but
try it out and tell me about any weird errors.  File uploads will definitely have some
problems.


== Install

It doesn't explicitly require Camping, but if you want to run the examples/camping/
examples then you'll need to install Camping 1.2 at least (and redcloth I think).  
These are all available from RubyGems.

The library consists of a C extension so you'll need a C compiler or at least a friend
who can build it for you.

Finally, the source includes a setup.rb for those who hate RubyGems.


== Usage

The examples/simpletest.rb file has the following code as the simplest
example:

 require 'mongrel'

 class SimpleHandler < Mongrel::HttpHandler
    def process(request, response)
      response.start(200) do |head,out|
        head["Content-Type"] = "text/plain"
        out.write("hello!\n")
      end
    end
 end

 h = Mongrel::HttpServer.new("0.0.0.0", "3000")
 h.register("/test", SimpleHandler.new)
 h.register("/files", DirHandler.new("."))
 h.run.join

If you run this and access port 3000 with a browser it will say
"hello!".  If you access it with any url other than "/test" it will
give a simple 404.  Check out the Mongrel::Error404Handler for a 
basic way to give a more complex 404 message.

This also shows the DirHandler with directory listings.  This is still
rough but it should work for basic hosting.  *File extension to mime
type mapping is missing though.*


== Speed

The 0.2.1 release probably consists of the most effort I've ever put into 
tuning a Ruby library for speed.  It consists of nearly everything I could think
of to make Mongrel the fastest Ruby HTTP library possible.  I've tried about 
seven different architectures and IO processing methods and none of them 
make it any faster.  In short:  Mongrel is amazingly fast considering Ruby's speed
limitations.

This release also brings in controllable threads that you can scale to meet your
needs to do your processing.  Simple pass in the HttpServer.new third optional
parameter:

 h = Mongrel::HttpServer.new("0.0.0.0", "3000", 40)

Which will make 40 thread processors.  Right now the optimal setting is up in
the air, but 20 seemed to be about the sweet spot on my systems.  The 
limited processors also means that you can use ActiveRecord as-is and it will
create a matching database connection for each processor thread.  More on 
this in future releases.

With this release I'm hoping that I've created a nice solid fast as hell core
upon which I can build the remaining features I want in Mongrel.

== The Future

With the core of Mongrel completed I'm now turning to the next set of features
to make Mongrel useful for hosting web applications in a heavily utilized
production environment.  Right now I'm looking at:

* An idea I've had for an insane caching handler which could speed up quite a
few deployments.

Overall though the goal of Mongrel is to be just enough HTTP to serve a Ruby
web application that sits behind a more complete web server.  Everything 
in the next will focus on actually hosting the major web frameworks for Ruby:

* Camping -- because it's already done (thanks Why).
* Ruby on Rails -- that's where my bread is buttered right now.
* Nitro -- Nitro folks have already hooked this up and started using it.  Nice.
* ????? -- Others people might be interested in.

== Contact

E-mail zedshaw at zedshaw.com and I'll help.  Comments about the API are welcome.