diff options
Diffstat (limited to 'activemodel/lib/active_model/observing.rb')
| -rw-r--r-- | activemodel/lib/active_model/observing.rb | 150 |
1 files changed, 125 insertions, 25 deletions
diff --git a/activemodel/lib/active_model/observing.rb b/activemodel/lib/active_model/observing.rb index ca206ee9aa..1114ac962a 100644 --- a/activemodel/lib/active_model/observing.rb +++ b/activemodel/lib/active_model/observing.rb @@ -9,6 +9,7 @@ require 'active_support/core_ext/object/try' require 'active_support/descendants_tracker' module ActiveModel + # == Active Model Observers Activation module Observing extend ActiveSupport::Concern @@ -17,9 +18,7 @@ module ActiveModel end module ClassMethods - # == Active Model Observers Activation - # - # Activates the observers assigned. Examples: + # Activates the observers assigned. # # class ORM # include ActiveModel::Observing @@ -35,34 +34,95 @@ module ActiveModel # ORM.observers = Cacher, GarbageCollector # # Note: Setting this does not instantiate the observers yet. - # +instantiate_observers+ is called during startup, and before + # <tt>instantiate_observers</tt> is called during startup, and before # each development request. def observers=(*values) observers.replace(values.flatten) end - # Gets an array of observers observing this model. - # The array also provides +enable+ and +disable+ methods - # that allow you to selectively enable and disable observers. - # (see <tt>ActiveModel::ObserverArray.enable</tt> and - # <tt>ActiveModel::ObserverArray.disable</tt> for more on this) + # Gets an array of observers observing this model. The array also provides + # +enable+ and +disable+ methods that allow you to selectively enable and + # disable observers (see ActiveModel::ObserverArray.enable and + # ActiveModel::ObserverArray.disable for more on this). + # + # class ORM + # include ActiveModel::Observing + # end + # + # ORM.observers = :cacher, :garbage_collector + # ORM.observers # => [:cacher, :garbage_collector] + # ORM.observers.class # => ActiveModel::ObserverArray def observers @observers ||= ObserverArray.new(self) end - # Gets the current observer instances. + # Returns the current observer instances. + # + # class Foo + # include ActiveModel::Observing + # + # attr_accessor :status + # end + # + # class FooObserver < ActiveModel::Observer + # def on_spec(record, *args) + # record.status = true + # end + # end + # + # Foo.observers = FooObserver + # Foo.instantiate_observers + # + # Foo.observer_instances # => [#<FooObserver:0x007fc212c40820>] def observer_instances @observer_instances ||= [] end # Instantiate the global observers. + # + # class Foo + # include ActiveModel::Observing + # + # attr_accessor :status + # end + # + # class FooObserver < ActiveModel::Observer + # def on_spec(record, *args) + # record.status = true + # end + # end + # + # Foo.observers = FooObserver + # + # foo = Foo.new + # foo.status = false + # foo.notify_observers(:on_spec) + # foo.status # => false + # + # Foo.instantiate_observers # => [FooObserver] + # + # foo = Foo.new + # foo.status = false + # foo.notify_observers(:on_spec) + # foo.status # => true def instantiate_observers observers.each { |o| instantiate_observer(o) } end - # Add a new observer to the pool. - # The new observer needs to respond to 'update', otherwise it - # raises an +ArgumentError+ exception. + # Add a new observer to the pool. The new observer needs to respond to + # <tt>update</tt>, otherwise it raises an +ArgumentError+ exception. + # + # class Foo + # include ActiveModel::Observing + # end + # + # class FooObserver < ActiveModel::Observer + # end + # + # Foo.add_observer(FooObserver.instance) + # + # Foo.observers_instance + # # => [#<FooObserver:0x007fccf55d9390>] def add_observer(observer) unless observer.respond_to? :update raise ArgumentError, "observer needs to respond to 'update'" @@ -70,16 +130,47 @@ module ActiveModel observer_instances << observer end - # Notify list of observers of a change. + # Fires notifications to model's observers. + # + # def save + # notify_observers(:before_save) + # ... + # notify_observers(:after_save) + # end + # + # Custom notifications can be sent in a similar fashion: + # + # notify_observers(:custom_notification, :foo) + # + # This will call <tt>custom_notification</tt>, passing as arguments + # the current object and <tt>:foo</tt>. def notify_observers(*args) observer_instances.each { |observer| observer.update(*args) } end - # Total number of observers. + # Returns the total number of instantiated observers. + # + # class Foo + # include ActiveModel::Observing + # + # attr_accessor :status + # end + # + # class FooObserver < ActiveModel::Observer + # def on_spec(record, *args) + # record.status = true + # end + # end + # + # Foo.observers = FooObserver + # Foo.observers_count # => 0 + # Foo.instantiate_observers + # Foo.observers_count # => 1 def observers_count observer_instances.size end + # <tt>count_observers</tt> is deprecated. Use #observers_count. def count_observers msg = "count_observers is deprecated in favor of observers_count" ActiveSupport::Deprecation.warn(msg) @@ -110,21 +201,30 @@ module ActiveModel end end - # Fires notifications to model's observers + # Notify a change to the list of observers. + # + # class Foo + # include ActiveModel::Observing # - # def save - # notify_observers(:before_save) - # ... - # notify_observers(:after_save) + # attr_accessor :status # end # - # Custom notifications can be sent in a similar fashion: + # class FooObserver < ActiveModel::Observer + # def on_spec(record, *args) + # record.status = true + # end + # end # - # notify_observers(:custom_notification, :foo) + # Foo.observers = FooObserver + # Foo.instantiate_observers # => [FooObserver] # - # This will call +custom_notification+, passing as arguments - # the current object and :foo. + # foo = Foo.new + # foo.status = false + # foo.notify_observers(:on_spec) + # foo.status # => true # + # See ActiveModel::Observing::ClassMethods.notify_observers for more + # information. def notify_observers(method, *extra_args) self.class.notify_observers(method, self, *extra_args) end @@ -238,7 +338,7 @@ module ActiveModel # Send observed_method(object) if the method exists and # the observer is enabled for the given object's class. def update(observed_method, object, *extra_args, &block) #:nodoc: - return if !respond_to?(observed_method) || disabled_for?(object) + return if !respond_to?(observed_method) || disabled_for?(object) send(observed_method, object, *extra_args, &block) end |