活动记录的简单Railtie扩展

Question

我要创建一个Rails 3.0.3的宝石，它不能获得工作：

# attached.rb
module Attached
  require 'attached/railtie' if defined?(Rails)
  def self.include(base)
    base.send :extend, ClassMethods
  end
  module ClassMethods
    def acts_as_fail
    end
  end
end

# attached/railtie.rb
require 'attached'
require 'rails'

module Attached
  class Railtie < Rails::Railtie
    initializer 'attached.initialize' do
      ActiveSupport.on_load(:active_record) do
        ActiveRecord::Base.send :include, Attached
      end
    end
  end
end

我得到undefined local variable or method 'acts_as_fail'当我添加acts_as_fail我的任何ActiveRecord模型。请帮忙！我非常有这个看似微不足道的代码沮丧！谢谢！

Answer 1

您正在定义self.include（第四线向下），当正确的方法是self.included。

Answer 2

可以通过直接使用extend简化的代码：

# attached.rb
module Attached
  require 'attached/railtie' if defined?(Rails)
  def acts_as_fail
  end
end

# attached/railtie.rb
require 'attached'
require 'rails'

module Attached
  class Railtie < Rails::Railtie
    initializer 'attached.initialize' do
      ActiveSupport.on_load(:active_record) do
        ActiveRecord::Base.send :extend, Attached
      end
    end
  end
end

这是一个良好的阅读： http://yehudakatz.com/2009/11/12/better-ruby-成语/