Demonstrate an edge case where RabbitMQ's Bunny Channel#wait_for_confirms may hand until it timeouts

demonstrate-bunny-wait_for_confirms-timeout.rb

require 'thread'
require 'bunny'

c = Bunny::Session.new(continuation_timeout: 1_000)
c.start

ch = c.create_channel

ch.confirm_select

x = ch.direct('test-exchange', durable: true)
q = ch.queue('', exclusive: true)
q.bind(x, routing_key: q.name)

# Delete the test exchange to cause a channel-level error
second_channel = c.create_channel
second_channel.exchange_delete(x.name)

puts 'Publishing (to a deleted channel)...'
x.publish('foobar', routing_key: q.name)

puts 'Waiting for confirms - it will timeout...'
x.wait_for_confirms