Method: ActiveModel::Callbacks#define_model_callbacks

Defined in:
lib/active_model/callbacks.rb

#define_model_callbacks(*callbacks) ⇒ Object

define_model_callbacks accepts the same options define_callbacks does, in case you want to overwrite a default. Besides that, it also accepts an :only option, where you can choose if you want all types (before, around or after) or just some.

define_model_callbacks :initializer, :only => :after

Note, the :only => <type> hash will apply to all callbacks defined on that method call. To get around this you can call the define_model_callbacks method as many times as you need.

define_model_callbacks :create, :only => :after
define_model_callbacks :update, :only => :before
define_model_callbacks :destroy, :only => :around

Would create after_create, before_update and around_destroy methods only.

You can pass in a class to before_<type>, after_<type> and around_<type>, in which case the callback will call that class’s <action>_<type> method passing the object that the callback is being called on.

class MyModel
  extend ActiveModel::Callbacks
  define_model_callbacks :create

  before_create AnotherClass
end

class AnotherClass
  def self.before_create( obj )
    # obj is the MyModel instance that the callback is being called on
  end
end



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# File 'lib/active_model/callbacks.rb', line 88

def define_model_callbacks(*callbacks)
  options = callbacks.extract_options!
  options = {
     :terminator => "result == false",
     :scope => [:kind, :name],
     :only => [:before, :around, :after]
  }.merge(options)

  types = Array.wrap(options.delete(:only))

  callbacks.each do |callback|
    define_callbacks(callback, options)

    types.each do |type|
      send("_define_#{type}_model_callback", self, callback)
    end
  end
end