Testing Postgres Listen/Notify using EventMachine

gistfile1.rb

require 'rubygems'
require 'pg'
require 'eventmachine'

module Subscriber
  def initialize(pg)
    @pg = pg
  end

  def notify_readable
    @pg.consume_input
    
    while notification = @pg.notifies
      puts notification.inspect
    end
  end

  def unbind
    @pg.close
  end
end

pg = PGconn.connect(:dbname => 'postgres')
pg.exec "set application_name = 'test'"
pg.exec "LISTEN test"

EM.run do
  EM.watch(pg.socket, Subscriber, pg) { |c| c.notify_readable = true }
end