Event loop with callback register class

callbacks_register.rb

class CallbackRegister

  def initialize
    @callbacks = {read: [], write: []}
  end

  def each(type, &block)
    @callbacks[type].each do |callback|
      yield callback
    end
  end

  def push(callback, type)
    @callbacks[type] << callback
  end
end

big_file = "network/path/big_file.xlsx"
file_handler = open(big_file)
files_to_look_after = [file_handler]

# Before we start the event loop we get our register class
# from container manager, possibly something like
# https://dry-rb.org/gems/dry-container/0.8/
register = get_callback_register_from_container_manager

# Event loop
loop do
  puts "(Re)Starting the Event loop"
  readable, _writeable = IO.select files_to_look_after, [], [], 0.01

  # 2. Step: Handle readable connection
  if readable
    readable.each do |ready_io|
      # We will read 4096 bytes in each iteration
      read_data = ready_io.read_nonblock(4096)

      # 3. Step: Process data according to business logic
      register.each(:read) do |callback|
        # Here we can prepocess something if need then we
        # call our callback
        callback.call(ready_io, read_data)
        # Again, we can do something after the callback
        # is finished
      end
    rescue EOFError => e
      files_to_look_after.reject! {|file| file == ready_io }
    end
  end

  break if files_to_look_after.empty?
end