== Rails Metal Demonstration App

This app supplements my 19 February 2009 presentation to NH Ruby 
(http://nhruby.org/) about Rack, Metal, and new features in Rails 2.3

== Points of Interest

app/metal/hello_metal.rb
  Very simple Hello World endpoint that responds to /hello/metal

app/controllers/hello_rails_controller.rb
  Duplicate functionality to the above except using the Rails stack.  Responds
  to /hello/rails

app/metal/hello_sinatra.rb
  Demonstrates any Rack application can be a Metal endpoint.  Responds to
  /hello/sintra

== Do It Yourself

Here's what's needed to recreate this app from scratch.

## Create stock app and freeze 2.3.0 
rails metal
cd metal
rake rails:freeze:edge RELEASE=2.3.0
rake rails:update

## Generate Metal endpoint
script/generate metal HelloMetal
cat app/metal/hello_metal.rb
  require(File.dirname(__FILE__) + "/../../config/environment") unless defined?(Rails)

  class HelloMetal
    def self.call(env)
      if env["PATH_INFO"] =~ /^\/hello\/metal/
        [200, {"Content-Type" => "text/plain"}, ["Hello, Metal!"]]
      else
        [404, {"Content-Type" => "text/html"}, ["Not Found"]]
      end
    end
  end

## Generate Rails controller
script/generate controller HelloRails
cat app/controllers/hello_rails_controller.rb
  class HelloRailsController < ApplicationController
    def show
      headers['Content-Type'] = 'text/plain'
      render :text => 'Hello, Rails!'
    end
  end

## Update routes for Rails controller
cat config/routes.rb
  ActionController::Routing::Routes.draw do |map|
    map.connect 'hello/rails', :controller => 'hello_rails', :action => 'show'
  end

## Create Sinatra app as Metal endpoint
## See Josh Peek's notes at 
##   http://github.com/rails/rails/commit/61a41154f7d50099da371e0d2f22fd25ab9113c2
sudo gem install sinatra
cat app/metal/hello_sinatra.rb
  require 'sinatra'
  Sinatra::Application.set(:run => false)
  Sinatra::Application.set(:environment => :production)

  HelloSinatra = Sinatra::Application.new unless defined? HelloSinatra
  
  get '/hello/sinatra' do
    response['Content-Type'] = 'text/plain'
    'Hello, Sinatra!'
  end