定義自定義對象生命週期的鉤子紅寶石

Question

所以我有一個對象，我想定義一個生命週期掛鉤，如before_create，after_create等

我想打電話給這個after_retire並將它安裝，所以我可以做以下：

class User < ActiveRecord::Base 
    include Active 
    after_retire :method 

    def method 
    #do stuff 
    end 
end 

到目前爲止，我有一個模塊的設置，像這樣，但我不斷收到一個未定義的方法在我的用戶模型after_retire錯誤。

module Active 
    extend ActiveSupport::Concern 

    included do 
    define_callbacks :retire 
    set_callback :retire, :after, :after_retire 
    default_scope { where(:retired => false) } 
    scope :retired, where(:retired => true) 
    end 

    def retire! 
    run_callbacks :retire do 
     update_attribute :retired, true 
     update_attribute :retired_at, Time.now.to_datetime 
    end 
    end 
end 

我該如何設置它？

Answer 1

before/after_callback語法通過#define_model_callbacks在ActiveModel :: Callbacks中處理。原始的ActiveSupport ::回調會要求您使用#set_callback沒有任何語法糖：

module Active 
    extend ActiveSupport::Concern 

    included do 
    define_callbacks :retire 
    default_scope { where(:retired => false) } 
    scope :retired, where(:retired => true) 
    end 

    def retire! 
    run_callbacks :retire do 
     update_attribute :retired, true 
     update_attribute :retired_at, Time.now.to_datetime 
    end 
    end 
end 

class User < ActiveRecord::Base 
    include Active 
    set_callback :retire, :after, :method 

    def method 
    #do stuff 
    end 
end 

如果你想有後/語法之前，因爲你是用一個ActiveRecord工作（並因此加載ActiveModel）類，您可以使用：

module Active 
    extend ActiveSupport::Concern 

    included do 
    define_model_callbacks :retire 
    default_scope { where(:retired => false) } 
    scope :retired, where(:retired => true) 
    end 

    def retire! 
    run_callbacks :retire do 
     update_attribute :retired, true 
     update_attribute :retired_at, Time.now.to_datetime 
    end 
    end 
end 

class User < ActiveRecord::Base 
    include Active 
    after_retire :method 

    def method 
    #do stuff 
    end 
end