factory2.rb

class SlackLogger
  def initialize(message)
    @message = message
  end
  def sending
    puts 'we sending message to Slack'
  end
end
class EmailLogger
  def initialize(message)
    @message = message
  end
  def sending
    puts 'we sending message to Email'
  end
end
class StorageLogger
  def initialize(message)
    @message = message
  end
  def sending
    puts 'we sending message to some storage'
  end
end

class AbstractLogging
  attr_reader :log_string, :logger_factory
  def initialize(log_string, logger_factory = nil)
    @log_string = log_string
    @logger_factory = logger_factory
  end

  def action
    raise 'logger_factory is not implemented' if logger_factory.nil?
    logger_factory.new(log_string).sending
  end
end

AbstractLogging.new('some error', SlackLogger).action
AbstractLogging.new('some error', EmailLogger).action
AbstractLogging.new('some error', StorageLogger).action