Consuming multiple queues with MarchHare's low-level api

test_multiple_queues.rb

require 'march_hare'
require 'pry'

connection = MarchHare.connect(thread_pool_size: 10, automatically_recover: false)
connection.start

channel = connection.create_channel

# create queues
queue_names = (1..3).map { |n| "queue#{n}" }
queues = queue_names.each do |name|
  channel.queue(name)
end

# create consumer. meh api :(
# note: recover_from_network_failure is broken by passing a nil queue (second
# parameter) and this requires automatically_recover: false to be passed when creating
# the connection to it doesn't get triggered
consumer = MarchHare::CallbackConsumer.new(channel, nil, {}, proc { |headers, message|
  puts "Got #{message} (Thread=#{Thread.current.object_id})"
  sleep 2
  channel.basic_ack(headers.envelope.delivery_tag, false)
})

# listen to queues
queue_names.each do |name|
  puts "Setting up consume of #{name}"
  channel.basic_consume(name, false, consumer)
end

# publish message to each
queue_names.each do |name|
  channel.default_exchange.publish("Hello from #{name}!", routing_key: name)
end

sleep 10
connection.close

From reading the code I thought the consumer would be submitted to the thread_pool to be executed. Ran it locally and it is done sequentially... that is weird.