Chain a set of commands

chainer.rb

module Chainer

  STATUSES = [ STATUS_SUCCESS = :success, STATUS_FAIL = :fail ]

  def self.execute(context, *steps)
    steps.each do |step|
      step.execute context
      break if context.fail?
    end
    context
  end

  module Context
    extend ActiveSupport::Concern

    def status
      @status || Chainer::STATUS_SUCCESS
    end

    def message
      @message
    end

    def set_fail!(message)
      self.message = message
      self.status  = Chainer::STATUS_FAIL
    end

    def success?
      self.status == Chainer::STATUS_SUCCESS
    end

    def fail?
      not success?
    end

    private

    def status=(value)
      @status = value
    end

    def message=(value)
      @message = value
    end

  end
end