EventMachine example

Bash -- 1

krzysztof@samsung:~$ socat unix-connect:/tmp/test.sock stdin
This is a test.
krzysztof@samsung:~$ socat unix-connect:/tmp/test.sock stdin
This is also a test.
krzysztof@samsung:~$ 

Bash -- 2

krzysztof@samsung:~$ ruby em-test.rb 
I, [2012-08-19T00:39:55.485256 #22753]  INFO -- : Got: This is a test.
I, [2012-08-19T00:40:02.388188 #22753]  INFO -- : Got: This is also a test.
^C
krzysztof@samsung:~$ 

unix-socket-server.rb

#!/usr/bin/env ruby

require 'logger'

begin
  require 'eventmachine'
rescue LoadError
  require 'rubygems'
  require 'eventmachine'
end

module Test
  class Server
    class << self
      def channel
        @@channel ||= EventMachine::Channel.new
      end
    end

    def initialize(socket_path, options={})
      @socket_path = socket_path

      @channel = Test::Server.channel
      @log     = Logger.new(STDOUT)

      @log.level = Logger::DEBUG
    end

    def start
      @channel.subscribe {|data| process_incoming_data(data) }

      EventMachine.run do
        EventMachine.start_unix_domain_server(@socket_path, Server::Connection)
      end
    end

    def stop
      EventMachine.next_tick { EventMachine.stop rescue nil }
    end

    private

    def process_incoming_data(data)
      @log.info("Got: #{data.strip}")
    end

    class Connection < EventMachine::Connection
      def initialize
        super
        @channel = Test::Server.channel
      end

      def receive_data(data)
        @channel.push(data)
        close_connection
      end
    end
  end
end

if $0 == __FILE__
  ts = Test::Server.new('/tmp/test.sock')

  Kernel.trap('INT') { ts.stop }

  ts.start
end

# vim: set ts=2 sw=2 et :
# encoding: utf-8