Bunny gem for AMQP Spike

bunny.rb

require "bunny"

# Start a communication session with RabbitMQ
conn = Bunny.new
conn.start

# open a channel
ch = conn.create_channel

# declare a queue
q  = ch.queue("test1")

# publish a message to the default exchange which then gets routed to this queue
q.publish("Hello, everybody!")

# fetch a message from the queue
delivery_info, metadata, payload = q.pop

puts "This is the message: #{payload}"

# close the connection
conn.stop

consumer.rb

require "amqp"
require "yaml"

t = Thread.new { EventMachine.run }
sleep(0.5)

connection = AMQP.connect
channel    = AMQP::Channel.new(connection, :auto_recovery => true)
channel.on_error do |ch, channel_close|
  raise "Channel-level exception: #{channel_close.reply_text}"
end

channel.prefetch(1)

channel.queue("test1").subscribe do |metadata, payload|
  puts "Received: #{payload}"
end

puts "[boot] Ready"
Signal.trap("INT") { connection.close { EventMachine.stop } }
t.join

notes.md

AMQP

http://rubyamqp.info/articles/getting_started/

RabbitMQ

http://www.rabbitmq.com/download.html

Gems

AMQP Gem

• http://rubyamqp.info/
• https://github.com/ruby-amqp/amqp/
• http://rubyamqp.info/articles/patterns_and_use_cases/

Integrating with Unicorn

• http://rubyamqp.info/articles/connecting_to_broker/

Bunny Gem

https://github.com/ruby-amqp/bunny

EventMachine

AMQP

• Prefetch
• Autodelete

Channels

Queues

• Queues store and forward messages to consumers. Queues are like mailboxes in SMTP.
• Messages are first delivered to exchanges which route messages to queues using rules called bindings.
• Queues and binding are declared by apps.

Queue Attributes

• Name
• Durability
• Whether the queue is auto-deleted when no longer used
• Other metadata (sometimes called X-arguments)

Queue Naming

• Queues contain several segments separated by a dot, like URI path segments and /
• Before use, queue must be declared
  • Will be created if doesn't exist
  • No effect if queue already does exist and its attributes are the same as the declaration
  • Channel-level exception is raised if attributes don't match
  • e.g. to declare queue named "images.resize":

    queue = AMQP::Queue.new(channel, "images.resize", :auto_delete => true)
    

Exchanges

Durability

• http://rubyamqp.info/articles/durability/

publisher.rb

require "bunny"

# Start a communication session with RabbitMQ
conn = Bunny.new
conn.start

# open a channel
ch = conn.create_channel

# declare a queue
q  = ch.queue("test1")

loop do
  # publish a message to the default exchange which then gets routed to this queue
  puts "Sending..."
  q.publish("Hello, everybody!")
  sleep 5
end