Module | ActiveRecord::Observing::ClassMethods |
In: |
vendor/rails/activerecord/lib/active_record/observer.rb
|
Instantiate the global ActiveRecord observers
# File vendor/rails/activerecord/lib/active_record/observer.rb, line 26 26: def instantiate_observers 27: return if @observers.blank? 28: @observers.each do |observer| 29: if observer.respond_to?(:to_sym) # Symbol or String 30: observer.to_s.camelize.constantize.instance 31: elsif observer.respond_to?(:instance) 32: observer.instance 33: else 34: raise ArgumentError, "#{observer} must be a lowercase, underscored class name (or an instance of the class itself) responding to the instance method. Example: Person.observers = :big_brother # calls BigBrother.instance" 35: end 36: end 37: end
Activates the observers assigned. Examples:
# Calls PersonObserver.instance ActiveRecord::Base.observers = :person_observer # Calls Cacher.instance and GarbageCollector.instance ActiveRecord::Base.observers = :cacher, :garbage_collector # Same as above, just using explicit class references ActiveRecord::Base.observers = Cacher, GarbageCollector
# File vendor/rails/activerecord/lib/active_record/observer.rb, line 21 21: def observers=(*observers) 22: @observers = observers.flatten 23: end