Another example of https://github.com/eventmachine/eventmachine/issues/477

console output.txt

bbozo@vilma:~/dev/0000_dallywagging/rabbitmq$ rvm use ruby
Using /home/bbozo/.rvm/gems/ruby-2.0.0-p247
bbozo@vilma:~/dev/0000_dallywagging/rabbitmq$ ruby amqp_hello.rb 
Connecting to RabbitMQ. Running 1.1.1 version of the gem...
amqpgem.examples.hello_world
================================================================================
foo
roko
Received a message: Hello, world!. Disconnecting...
tick
tick

bbozo@vilma:~/dev/0000_dallywagging/rabbitmq$ rvm use jruby
Using /home/bbozo/.rvm/gems/jruby-1.7.5
bbozo@vilma:~/dev/0000_dallywagging/rabbitmq$ ruby amqp_hello.rb 
Connecting to RabbitMQ. Running 1.1.1 version of the gem...
amqpgem.examples.hello_world
================================================================================
foo

em_jruby_issue_with_amqp.rb

#!/usr/bin/env ruby
# encoding: utf-8

require "amqp"
require "eventmachine"
require "pry"

unless EM.reactor_running?

  Thread.abort_on_exception = true
  Thread.new do
    EM.run do
      AMQP.channel ||= AMQP::Channel.new(AMQP.connect(:host => '127.0.0.1'))
    end
  end

end
until EM.reactor_running?; sleep 0.1; end
EM.next_tick{}

EM::add_periodic_timer 1 do
  puts "tick"
end


connection = AMQP.connect(:host => '127.0.0.1')
puts "Connecting to RabbitMQ. Running #{AMQP::VERSION} version of the gem..."

ch  = AMQP::Channel.new(connection)
q   = ch.queue("amqpgem.examples.hello_world", :auto_delete => true)
x   = ch.default_exchange

q.subscribe do |metadata, payload|
  puts "Received a message: #{payload}. Disconnecting..."
end

puts q.name
x.publish "Hello, world!", :routing_key => q.name


module Messaging
  class RabbitMqWrapper

    attr_accessor :channel, :queue, :exchange, :options

    def initialize(queue, options = {})
      @channel = AMQP.channel
      @queue = channel.queue(queue, :auto_delete => true)
      @exchange = channel.default_exchange

      @options = {}
    end

    def self.start(*args, &block)
      new(*args, &block)
    end

    def publish payload
      puts queue.name
      exchange.publish payload, :routing_key => queue.name
    end

    def subscribe &block
      queue.subscribe &block
    end

  end
end

puts "="*80
queue = Messaging::RabbitMqWrapper.new('foo')
queue.subscribe do |metadata, payload|
  puts payload
end
queue.publish 'roko'

sleep 3
EM.stop