Bunny dead letter exchange test

dead_letter_exchange_test.rb

require 'bunny'

number_of_messages = 10

queue_name = 'contact'

connection = Bunny.new

connection.start

channel = connection.create_channel

exchange = channel.fanout("#{queue_name}.exchange")

retry_exchange = channel.fanout("#{queue_name}.retry.exchange")

retry_queue = channel.queue("#{queue_name}_retry", arguments: { 'x-dead-letter-exchange' => exchange.name, 'x-message-ttl' => 2000 }).bind(retry_exchange)

queue = channel.queue(queue_name).bind(exchange)

successes = 0

queue.subscribe do |_delivery_info, _metadata, payload|
  puts '*' * 100

  puts Time.now

  puts payload

  if rand(2) == 1
    puts "Failed! (#{successes} / #{number_of_messages})"

    retry_exchange.publish(payload)
  else
    successes += 1

    puts "Success! (#{successes} / #{number_of_messages})"
  end

  puts '*' * 100

  puts
end

number_of_messages.times do |i|
  puts "\nPublishing message #{i}."

  exchange.publish("Message ##{i}", routing_key: queue.name)
end

loop do
  puts "\n#{successes} / #{number_of_messages} messages processed."

  break if successes == number_of_messages

  sleep 1
end

retry_exchange.delete

puts "Disconnecting..."

connection.close