aggregate_manager.rb

require "concurrent/actress"

module EventSourcing
  class AggregateManager
    include Concurrent::Actress::Context

    def initialize
      @registry = {}
    end

    def on_message(message)
      instance_of(message[1], message[2]).message(message)
    end

    private
    def instance_of(klass, id)
      unless @registry[id] && !@registry[id].terminated?
        @registry[id] = klass.spawn!(id)
      end
      @registry[id]
    end
  end
end