box-o-sand/ruby-sockets/marco-polo/em-server.rb

require 'eventmachine'
require 'sequel'

if ENV['MPDB']
  DB = Sequel.connect(ENV['MPDB'])
else
  DB = Sequel.connect('sqlite://marco-polo.sqlite3')
end

begin
  DB[:locations].empty?
rescue Sequel::DatabaseError
  DB.create_table(:locations) do
    primary_key :id
    String :client
    Integer :x
    Integer :y
  end
end

module MarcoPoloServer
  def post_init
    @locations = DB[:locations]
  end

  def receive_data(data)
    client, x, y = data.split
    @locations.insert(:client => client, :x => x.to_i, :y => y.to_i)
    send_data("thanks\n")
  rescue => e
    STDERR.puts("#{e.class.name} #{e.message}: #{e.backtrace.join("\n")}")
  end
end

EventMachine.run do
  host, port = '0.0.0.0', 22000
  EventMachine.start_server(host, port, MarcoPoloServer)
  puts "Listening on #{host}:#{port}"
end