模型中的覆盖保存方法

Question

I'm new to Ruby/Rails and I want to override the save method so I can do some checking inside myself before calling the actual save method, however, I am getting this exception for some reason:

#<NoMethodError: undefined method `save' for true:TrueClass>

This is my code for the module and class.

Module:

module OverrideSave

    def save
        super.save if some_condition_true
    end
  end

Class:

class CardTransaction
  include Mongoid::Document
  include Mongoid::Timestamps::Created
  prepend OverrideSave

  field :type, type: String
  field :transaction_value, type: BigDecimal
  field :receipt_value, type: BigDecimal
  field :store_id, type: String

  belongs_to :card
end

I'm not sure what went wrong, any ideas?

Answer 1

Why do you try to call save on whatever super (ie save ) returns? From your description, you want something like this:

def save
  # some additional work
  super
end

Answer 2

You don't need to override the save method for above. You can use before_save callback in your model:

class CardTransaction
  before_save :do_some_validation

  private

  def do_some_validation
    # will get there before the save is called
    false if custom_validation
  end
end

Answer 3

As stated by @Marek

module OverrideSave

    def save
        super if some_condition_true
    end
end

But it is not good behavior to override save method, it would be better to create a new method which would use save method, so you still have save method.

module OverrideSave
  def save_with_guard
     save if some_condition_true
  end
end