nnabeyang/application.rb

## application.css
div {
}

## application.rb
require './static'
class Application
  class << self
    def instance
      @instance ||= new
    end
    def method_missing(*args, &block)
      instance.send(*args, &block)
    end
  end
  def app
    @app ||= begin
      stack = MiddlewareStack.new
      stack.use Static, File.dirname(__FILE__)
      stack.build(Hello.new)
    end
  end
  def call(env)
    app.call(env)
  end
end
class Hello
  def call(env)
    [200, {'Content-type' => 'text/html'}, [<<-HTML
<html>
  <title>hello</title>
  <body>
  <h1>hello</h1>
  </body>
</html>
HTML
]]
  end
end

## config.ru
require './application'
run Application

## index.html
<html>
<title>INDEX</title>
<body>
<h1>INDEX PAGE</h1>
</body>
</html>

## static.rb
require 'rack/file'
class FileHandler
  def initialize(root)
    @root = root.chomp('/')
    @file_server = ::Rack::File.new(@root)
  end
  def match?(path)
    full_path = File.join(@root, path)
    matches = Dir["#{full_path}{,.html,index.html}"]
    match = matches.detect {|m| File.file?(m)}
    match.sub!(/^#{@root}\//, '') if match
  end
  def call(env)
    @file_server.call(env)
  end
end
class Static
  def initialize(app, root)
    @app = app
    @file_handler = FileHandler.new(root)
  end
  def call(env)
     case env['REQUEST_METHOD']
     when 'GET', 'HEAD'
       if path = @file_handler.match?(env['PATH_INFO'])
         env['PATH_INFO'] = path
         return @file_handler.call(env)
       end
     end
     @app.call(env)
  end
end
class MiddlewareStack
  class Middleware
    def initialize(klass, opts)
      @klass = klass
      @opts = opts
    end
    def build(app)
      @klass.new(app, *@opts)
    end
  end
  def middlewares
    @middlewares ||= []
  end
  def use klass, *opts
    middlewares.unshift(self.class::Middleware.new(klass, opts))
  end
  def build app
    middlewares.inject(app) {|a, m| m.build(a)}
  end
end

## test.rb
#!/usr/bin/ruby1.9.1
require 'test/unit'
require 'rack/mock'
require './static'
require './application'
class Tests < Test::Unit::TestCase
  def test_file_handler_match
    original_dir = Dir.pwd
    root = File.expand_path('../data', __FILE__)
    Dir.chdir(root)
    handler = FileHandler.new(root)
    assert_equal 'index.html', handler.match?('')
    assert_nil handler.match?('no_such_file')
    assert_equal 'assets/application.css', handler.match?('assets/application.css')
  ensure
   Dir.chdir(original_dir)
  end
  def test_file_handler_get
    root = File.expand_path('../data', __FILE__)
    file_handler = FileHandler.new(root)
    path = file_handler.match? 'assets/application.css'
    res = ::Rack::MockRequest.new(FileHandler.new(root)).get(path)
    assert res.ok?
  end
  def test_static
    root = File.expand_path('../data', __FILE__)
    stack = MiddlewareStack.new
    stack.use ::Rack::MockRequest
    stack.use Static, root
    ran = false
    req = stack.build(proc {ran = true; [200, {}, []]})
    assert_match /div/, req.get('assets/application.css').body
    assert !ran
    req.get('no_such_file')
    assert ran
  end
  def test_application
    req = ::Rack::MockRequest.new(Application)
    assert_match /div/, req.get('data/assets/application.css').body
    assert_match /INDEX/, req.get('data/').body
    assert_match /INDEX/, req.get('data/index').body
    assert_match /INDEX/, req.get('data/index.html').body
    assert_match /hello/, req.get('no_such_file').body
  end

end
	require './static'
	class Application
	class << self
	def instance
	@instance \|\|= new
	end
	def method_missing(*args, &block)
	instance.send(*args, &block)
	end
	end
	def app
	@app \|\|= begin
	stack = MiddlewareStack.new
	stack.use Static, File.dirname(__FILE__)
	stack.build(Hello.new)
	end
	end
	def call(env)
	app.call(env)
	end
	end
	class Hello
	def call(env)
	[200, {'Content-type' => 'text/html'}, [<<-HTML
	<html>
	<title>hello</title>
	<body>
	<h1>hello</h1>
	</body>
	</html>
	HTML
	]]
	end
	end
	<html>
	<title>INDEX</title>
	<body>
	<h1>INDEX PAGE</h1>
	</body>
	</html>
	require 'rack/file'
	class FileHandler
	def initialize(root)
	@root = root.chomp('/')
	@file_server = ::Rack::File.new(@root)
	end
	def match?(path)
	full_path = File.join(@root, path)
	matches = Dir["#{full_path}{,.html,index.html}"]
	match = matches.detect {\|m\| File.file?(m)}
	match.sub!(/^#{@root}\//, '') if match
	end
	def call(env)
	@file_server.call(env)
	end
	end
	class Static
	def initialize(app, root)
	@app = app
	@file_handler = FileHandler.new(root)
	end
	def call(env)
	case env['REQUEST_METHOD']
	when 'GET', 'HEAD'
	if path = @file_handler.match?(env['PATH_INFO'])
	env['PATH_INFO'] = path
	return @file_handler.call(env)
	end
	end
	@app.call(env)
	end
	end
	class MiddlewareStack
	class Middleware
	def initialize(klass, opts)
	@klass = klass
	@opts = opts
	end
	def build(app)
	@klass.new(app, *@opts)
	end
	end
	def middlewares
	@middlewares \|\|= []
	end
	def use klass, *opts
	middlewares.unshift(self.class::Middleware.new(klass, opts))
	end
	def build app
	middlewares.inject(app) {\|a, m\| m.build(a)}
	end
	end
	#!/usr/bin/ruby1.9.1
	require 'test/unit'
	require 'rack/mock'
	require './static'
	require './application'
	class Tests < Test::Unit::TestCase
	def test_file_handler_match
	original_dir = Dir.pwd
	root = File.expand_path('../data', __FILE__)
	Dir.chdir(root)
	handler = FileHandler.new(root)
	assert_equal 'index.html', handler.match?('')
	assert_nil handler.match?('no_such_file')
	assert_equal 'assets/application.css', handler.match?('assets/application.css')
	ensure
	Dir.chdir(original_dir)
	end
	def test_file_handler_get
	root = File.expand_path('../data', __FILE__)
	file_handler = FileHandler.new(root)
	path = file_handler.match? 'assets/application.css'
	res = ::Rack::MockRequest.new(FileHandler.new(root)).get(path)
	assert res.ok?
	end
	def test_static
	root = File.expand_path('../data', __FILE__)
	stack = MiddlewareStack.new
	stack.use ::Rack::MockRequest
	stack.use Static, root
	ran = false
	req = stack.build(proc {ran = true; [200, {}, []]})
	assert_match /div/, req.get('assets/application.css').body
	assert !ran
	req.get('no_such_file')
	assert ran
	end
	def test_application
	req = ::Rack::MockRequest.new(Application)
	assert_match /div/, req.get('data/assets/application.css').body
	assert_match /INDEX/, req.get('data/').body
	assert_match /INDEX/, req.get('data/index').body
	assert_match /INDEX/, req.get('data/index.html').body
	assert_match /hello/, req.get('no_such_file').body
	end

	end