保護ruby對象屬性不被訪問

Question

什麼是保護屬性的最佳方式？請參閱以下幾點：

class Document 

    # no method outside this class can access this directly. If they call document.data, error should be thrown. including in any rendering 
    field sensitive_data 

    # but this method can be accessed by anyone 
    def get_sensitive_data 
    # where I apply the right protection 
    end 

end 

Answer 1

使用protected關鍵字。

class Document 

    # but this method can be accessed by anyone 
    def get_sensitive_data 
    # where I apply the right protection 
    end 

    protected # or private if you don't want a child class accesses it (Thx @toch) 

    # no method outside this class can access this directly. If they call document.data, error should be thrown. including in any rendering 
    field sensitive_data 


end 

記住，即使這只是隱藏的getter/setter，任何人都可以檢索使用send例如值。

Answer 2

無法阻止某人訪問該數據。無論您是否想要，元編程都會暴露出班級的所有內部元素。

也就是說，將get_sensitive_data標記爲protected或private將至少防止意外調用get_sensitive_data方法。