AMQP/RabbitMQ-Server/EventMachine with PhusionPassenger/Rails Crashes

Question

I'm using AMQP / RabbitMQ for my Ruby on Rails app.

I put the following amqp.rb file under config/initializers: (Copied and changed from a Recipe: http://www.hiringthing.com/2011/11/04/eventmachine-with-rails.html#sthash.iqCWUtOn.dpbs)

require 'amqp'

# References:
#   1. Getting Started with AMQP and Ruby
#      http://rubyamqp.info/articles/getting_started/
#   2. EventMachine and Rails
#      http://www.hiringthing.com/2011/11/04/eventmachine-with-rails.html#sthash.iqCWUtOn.dpbs
#   3. Connecting to the broker, integrating with Ruby on Rails, Merb and Sinatra
#      http://rubyamqp.info/articles/connecting_to_broker/
module AppEventMachine
  def self.start
    if defined?(PhusionPassenger)
      Rails.logger.info "###############################################################################"
      Rails.logger.info "Running EventMachine/Rails with PhusionPassenger ......"
      Rails.logger.info "###############################################################################"
      PhusionPassenger.on_event(:starting_worker_process) do |forked|
      # =>  for passenger, we need to avoid orphaned threads
        if forked && EventMachine.reactor_running?
          EventMachine.stop
        end

        spawn_eventmachine_thread
        die_gracefully_on_signal
      end
    else
      Rails.logger.info "###############################################################################"
      Rails.logger.info "PhusionPassenger is not running.  Probably you are running Rails locally ......"
      Rails.logger.info "###############################################################################"

      # faciliates debugging
      Thread.abort_on_exception = true
      # just spawn a thread and start it up
      spawn_eventmachine_thread unless defined?(Thin)
      # Thin is built on EventMachine, doesn't need this thread
    end
  end

  def self.spawn_eventmachine_thread
    Thread.new {
Rails.logger.error "**************************Begin"
      EventMachine.run do
Rails.logger.error "**************************1"
        AMQP.channel ||= AMQP::Channel.new(AMQP.connect(:host => '127.0.0.1')) # Q_SERVER, :user=> Q_USER, :pass => Q_PASS, :vhost => Q_VHOST ))
Rails.logger.error "**************************2"
        AMQP.channel.on_error(&method(:handle_channel_exception))
Rails.logger.error "**************************3"
        AMQP.channel.queue(MixpanelJob::QUEUE_NAME, :exclusive => true)
                    .subscribe { |metadata, payload| MixpanelJob::handle_sending(metadata, payload) }
Rails.logger.error "**************************4"
      end
Rails.logger.error "***************************End"
    }
  end

  def self.handle_channel_exception(channel, channel_close)
    Rails.logger.error "###############################################################################"
    Rails.logger.error "Oops... a channel-level exception: code = #{channel_close.reply_code}, message = #{channel_close.reply_text}"
    Rails.logger.error "###############################################################################"
  end

  def self.die_gracefully_on_signal
    Signal.trap("INT") {
      Rails.logger.error "###############################################################################"
      Rails.logger.error "Stopping the EventMachine ......"
      EventMachine.stop
      Rails.logger.error "###############################################################################"
    }
    Signal.trap("TERM") {
      Rails.logger.error "###############################################################################"
      Rails.logger.error "Stopping the EventMachine ......"
      EventMachine.stop
      Rails.logger.error "###############################################################################"
    }
  end
end

AppEventMachine.start

But when I start the server and try to browser to its root, I got:

###############################################################################
Running EventMachine/Rails with PhusionPassenger ......
###############################################################################
**************************Begin


Started GET "/" for 10.130.40.254 at 2013-07-29 18:54:07 -0400
**************************1
**************************2
**************************3
**************************4
Processing by UsersController#my_app as HTML
Completed 500 Internal Server Error in 1ms

TypeError ([9] is not a symbol):
  activesupport (3.2.3) lib/active_support/inflector/methods.rb:229:in `const_defined?'
  activesupport (3.2.3) lib/active_support/inflector/methods.rb:229:in `block in constantize'
  activesupport (3.2.3) lib/active_support/inflector/methods.rb:228:in `each'
  activesupport (3.2.3) lib/active_support/inflector/methods.rb:228:in `constantize'
  devise (2.1.2) lib/devise/rails/warden_compat.rb:27:in `deserialize'
  warden (1.2.1) lib/warden/session_serializer.rb:35:in `fetch'
  warden (1.2.1) lib/warden/proxy.rb:212:in `user'
  warden (1.2.1) lib/warden/proxy.rb:318:in `_perform_authentication'
  warden (1.2.1) lib/warden/proxy.rb:127:in `authenticate!'
  devise (2.1.2) lib/devise/controllers/helpers.rb:48:in `authenticate_user!'
  activesupport (3.2.3) lib/active_support/callbacks.rb:429:in `_run__125924433__process_action__89218244__callbacks'
  activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `__run_callback'
  activesupport (3.2.3) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
  activesupport (3.2.3) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (3.2.3) lib/abstract_controller/callbacks.rb:17:in `process_action'
  actionpack (3.2.3) lib/action_controller/metal/rescue.rb:29:in `process_action'
  actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
  activesupport (3.2.3) lib/active_support/notifications.rb:123:in `block in instrument'
  activesupport (3.2.3) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
  activesupport (3.2.3) lib/active_support/notifications.rb:123:in `instrument'
  actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
  actionpack (3.2.3) lib/action_controller/metal/params_wrapper.rb:205:in `process_action'
  activerecord (3.2.3) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
  actionpack (3.2.3) lib/abstract_controller/base.rb:121:in `process'
  actionpack (3.2.3) lib/abstract_controller/rendering.rb:45:in `process'
  actionpack (3.2.3) lib/action_controller/metal.rb:203:in `dispatch'
  actionpack (3.2.3) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
  actionpack (3.2.3) lib/action_controller/metal.rb:246:in `block in action'
  actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:73:in `call'
  actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
  actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:36:in `call'
  journey (1.0.4) lib/journey/router.rb:68:in `block in call'
  journey (1.0.4) lib/journey/router.rb:56:in `each'
  journey (1.0.4) lib/journey/router.rb:56:in `call'
  actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:600:in `call'
  warden (1.2.1) lib/warden/manager.rb:35:in `block in call'
  warden (1.2.1) lib/warden/manager.rb:34:in `catch'
  warden (1.2.1) lib/warden/manager.rb:34:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
  rack (1.4.4) lib/rack/etag.rb:23:in `call'
  rack (1.4.4) lib/rack/conditionalget.rb:25:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/head.rb:14:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/flash.rb:242:in `call'
  rack (1.4.4) lib/rack/session/abstract/id.rb:210:in `context'
  rack (1.4.4) lib/rack/session/abstract/id.rb:205:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/cookies.rb:338:in `call'
  activerecord (3.2.3) lib/active_record/query_cache.rb:64:in `call'
  activerecord (3.2.3) lib/active_record/connection_adapters/abstract/connection_pool.rb:467:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
  activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `_run__178400477__call__834586844__callbacks'
  activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `__run_callback'
  activesupport (3.2.3) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
  activesupport (3.2.3) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (3.2.3) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
  railties (3.2.3) lib/rails/rack/logger.rb:26:in `call_app'
  railties (3.2.3) lib/rails/rack/logger.rb:16:in `call'
  actionpack (3.2.3) lib/action_dispatch/middleware/request_id.rb:22:in `call'
  rack (1.4.4) lib/rack/methodoverride.rb:21:in `call'
  rack (1.4.4) lib/rack/runtime.rb:17:in `call'
  activesupport (3.2.3) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
  rack (1.4.4) lib/rack/lock.rb:15:in `call'
  rack-cache (1.2) lib/rack/cache/context.rb:136:in `forward'
  rack-cache (1.2) lib/rack/cache/context.rb:245:in `fetch'
  rack-cache (1.2) lib/rack/cache/context.rb:185:in `lookup'
  rack-cache (1.2) lib/rack/cache/context.rb:66:in `call!'
  rack-cache (1.2) lib/rack/cache/context.rb:51:in `call'
  railties (3.2.3) lib/rails/engine.rb:479:in `call'
  railties (3.2.3) lib/rails/application.rb:220:in `call'
  railties (3.2.3) lib/rails/railtie/configurable.rb:30:in `method_missing'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/rack/request_handler.rb:96:in `process_request'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_request_handler.rb:516:in `accept_and_process_next_request'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_request_handler.rb:274:in `main_loop'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/rack/application_spawner.rb:206:in `start_request_handler'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/rack/application_spawner.rb:171:in `block in handle_spawn_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/utils.rb:470:in `safe_fork'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/rack/application_spawner.rb:166:in `handle_spawn_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server.rb:357:in `server_main_loop'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server.rb:206:in `start_synchronously'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server.rb:180:in `start'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/rack/application_spawner.rb:129:in `start'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/spawn_manager.rb:253:in `block (2 levels) in spawn_rack_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server_collection.rb:132:in `lookup_or_add'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/spawn_manager.rb:246:in `block in spawn_rack_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server_collection.rb:82:in `block in synchronize'
  <internal:prelude>:10:in `synchronize'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server_collection.rb:79:in `synchronize'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/spawn_manager.rb:244:in `spawn_rack_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/spawn_manager.rb:137:in `spawn_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/spawn_manager.rb:275:in `handle_spawn_application'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server.rb:357:in `server_main_loop'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/lib/phusion_passenger/abstract_server.rb:206:in `start_synchronously'
  /home/passenger/.rvm/gems/ruby-1.9.3-p194/gems/passenger-3.0.19/helper-scripts/passenger-spawn-server:99:in `<main>'

Answer 1

Thanks to Joshua's comment. It turns out that it had nothing to do with PhusionPassenger or AMQP or RabbitMQ-Server. It's because of my Chrome cookies cache.

I cleared my cache, and now everything just works like charm.

Since my Rails throw an error, however, I think there is a bug in Ruby on Rails dealing with devise (or other gems) cookies.