a simple web server written in ruby-lang.

web_server.rb

require 'socket'

# --- func def for application

def application(name, &block)
 $app = Application.new
 $app.name = name
 $app.instance_eval(&block)
end


# --- class definition for Application

class Application
 attr_accessor :name

 def initialize
  @responders = {}
 end

 def open(client, path)
  responder = @responders[path]
  if responder
   responder.handle client
  else
   puts '>>> !no responder for ' + path
   @responders['/404'].handle client
  end 
 end
 
 def respond(path, &block)
  @responders[path] = Responder.new(&block)
 end

end


# --- class definition for Responder

class Responder
 def initialize(&block)
  @block = block
 end 

 def handle(client)
  @client = client
  instance_eval(&@block)
 end

 def say(words)
  @client.write(words)
  #puts words
 end
end


# --- DSL

application 'Test' do
 respond '/' do
  say 'you can try /work, /about or /ruby ;^D'
 end

 respond '/work' do
  say 'the work should be fun. like a game.'
 end

 respond '/about' do
  say 'a simple web server written in ruby-lang.'
 end

 respond '/ruby' do
  say 'Ruby is a dynamic, reflective, general purpose object-oriented programming language that combines syntax inspired by Perl with Smalltalk-like features. (from wikipedia)'
 end

 respond '/404' do
  say 'page not found'
 end
end


# --- Web Server: http://localhost:8080

server = TCPServer.new('localhost', 8080)
while client = server.accept
 peername = client.peeraddr[1,2].reverse.join ':'
 http_req = client.recv(1024)
 matches = /GET (.*) HTTP\/.*/i.match(http_req)
 if matches != nil && matches.length >= 2
  puts '>>> handle request ' + matches[1] + ' from ' + peername
  $app.open client, matches[1]
 else
  puts '>>> bad request from ' + peername
 end 
 client.close
end