s.rb

require 'socket'

class Page
  attr_reader :body, :method, :path
  def initialize(m, p, b)
    @body, @method, @path = b, m, p
  end
end

class Server
  attr_reader :pages
  def initialize
    @pages = []
  end
  def add_page(p)
    pages << p
  end
  alias << add_page
  def page_for(m, p)
    pages.find do |page|
      page.method == m && page.path == p
    end
  end
  def response_for(m, p)
    if page = page_for(m, p)
      [page, "HTTP/1.1 200 OK\r\nContent-Length: #{page.body.bytesize}\r\n\r\n#{page.body}"]
    else
      [nil, "HTTP/1.1 404 Not Found\r\nContent-Length: 14\r\n\r\nPage not found"]
    end
  end
end

server = Server.new
server << Page.new('GET', '/hello', 'Hello World')
stop =  Page.new('DELETE', '/world', 'Goodbye World')
server << stop

sock = TCPServer.new('0.0.0.0', 1337)

while client = sock.accept
  method, path = client.gets.split(' ')[0,2]
  page, response = server.response_for(method, path)
  client.write response
  break if page == stop
end