Non-leaking version of bunny logger memory leak test

test_fd_subscribe_memleak.rb

require 'bunny'
require 'logger'

class TestLoggerSubscribeMemleak
  def initialize(msg_count=10_000)
    @messages_to_write = msg_count
    @message_count = msg_count
    @connection = Bunny.new(:user=>"jbd_dev_reader", :pass=>"123456", :host=>"localhost", :vhost=>"jbd", :port=>5672)
    @connection.start
    @channel = @connection.create_channel
    @exchange = @channel.exchange('test_memleak', :type => :direct, :durable => false)
    @queue = @channel.queue('test_memleak', :durable => false, :auto_delete => false)
    @queue.bind(@exchange)
    @log = File.open("/tmp/test_memleak.log","a")
    @pong = 'PONG'
  end

  def run
    print_memory_use "Before start: "
    write_many_messages
    sleep 1
    print_memory_use "Post-write 1: "
    pop_all
    print_memory_use "Post-pop_all: "
    sleep 1
    write_many_messages
    print_memory_use "Post-write 2: "
    sleep 1
    do_subscribe
    sleep 1
    print_memory_use "Post-subscribe: "
  end

  def write_many_messages
    @queue.purge
    @messages_to_write.times {|t| @exchange.publish("HI#{t}") }
  end

  def print_memory_use(prepend='')
    memory_usage = `ps -o rss= -p #{$$}`.to_i
    @message_count = @queue.status[:message_count]
    $stderr.puts("#{prepend} RSS: #{memory_usage}; Pending Messages: #{@message_count}")
  end

  def pop_all
    nils=0
    loop do
      delivery_info, properties, payload = @queue.pop
      if payload.nil?
        nils += 1
      else
        @log.puts(@pong)
      end
      if nils > 10
        break
      end
    end
  end

  def do_subscribe
    messages_remaining = @message_count
    consumer = @queue.subscribe(:block => false) do |delivery_info, properties, payload|
      @log.puts(@pong)
      messages_remaining -= 1
    end
    while messages_remaining > 0
      sleep 0.5
    end
    consumer.cancel
  end

end

if $0 == __FILE__
  tester = TestLoggerSubscribeMemleak.new
  tester.run
end