herokuで1dynoで非同期処理を行う

EventMachineを使います。

app.rb

get '/async' do
  operation = proc {
    p 'operation started!'
    10.times do |i|
      puts "#{i} times Hello, Async!"
      sleep 1
    end
  }
  callback = proc {|result|
    p 'operation finished!'
  }
  EventMachine.defer(operation, callback)
  redirect '/'
end