Remove observers and sweepers

They was extracted from a plugin.

See https://github.com/rails/rails-observers

[Rafael Mendonça França + Steve Klabnik]

5 files changed, 4 insertions, 145 deletions

diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 5eacb8f143..965fe3f33a 100644
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -320,7 +320,6 @@ module ActiveRecord #:nodoc:
   # So it's possible to assign a logger to the class through <tt>Base.logger=</tt> which will then be used by all
   # instances in the current object space.
   class Base
-    extend ActiveModel::Observing::ClassMethods
     extend ActiveModel::Naming
 
     extend ActiveSupport::Benchmarkable
@@ -348,7 +347,6 @@ module ActiveRecord #:nodoc:
     include Locking::Pessimistic
     include AttributeMethods
     include Callbacks
-    include ActiveModel::Observing
     include Timestamp
     include Associations
     include ActiveModel::SecurePassword
diff --git a/activerecord/lib/active_record/observer.rb b/activerecord/lib/active_record/observer.rb
deleted file mode 100644
index 6b2f6f98a5..0000000000
--- a/activerecord/lib/active_record/observer.rb
+++ /dev/null
@@ -1,126 +0,0 @@
-
-module ActiveRecord
-  # = Active Record Observer
-  #
-  # Observer classes respond to life cycle callbacks to implement trigger-like
-  # behavior outside the original class. This is a great way to reduce the
-  # clutter that normally comes when the model class is burdened with
-  # functionality that doesn't pertain to the core responsibility of the
-  # class. Example:
-  #
-  #   class CommentObserver < ActiveRecord::Observer
-  #     def after_save(comment)
-  #       Notifications.comment("admin@do.com", "New comment was posted", comment).deliver
-  #     end
-  #   end
-  #
-  # This Observer sends an email when a Comment#save is finished.
-  #
-  #   class ContactObserver < ActiveRecord::Observer
-  #     def after_create(contact)
-  #       contact.logger.info('New contact added!')
-  #     end
-  #
-  #     def after_destroy(contact)
-  #       contact.logger.warn("Contact with an id of #{contact.id} was destroyed!")
-  #     end
-  #   end
-  #
-  # This Observer uses logger to log when specific callbacks are triggered.
-  #
-  # == Observing a class that can't be inferred
-  #
-  # Observers will by default be mapped to the class with which they share a name. So CommentObserver will
-  # be tied to observing Comment, ProductManagerObserver to ProductManager, and so on. If you want to name your observer
-  # differently than the class you're interested in observing, you can use the Observer.observe class method which takes
-  # either the concrete class (Product) or a symbol for that class (:product):
-  #
-  #   class AuditObserver < ActiveRecord::Observer
-  #     observe :account
-  #
-  #     def after_update(account)
-  #       AuditTrail.new(account, "UPDATED")
-  #     end
-  #   end
-  #
-  # If the audit observer needs to watch more than one kind of object, this can be specified with multiple arguments:
-  #
-  #   class AuditObserver < ActiveRecord::Observer
-  #     observe :account, :balance
-  #
-  #     def after_update(record)
-  #       AuditTrail.new(record, "UPDATED")
-  #     end
-  #   end
-  #
-  # The AuditObserver will now act on both updates to Account and Balance by treating them both as records.
-  #
-  # == Available callback methods
-  #
-  # The observer can implement callback methods for each of the methods described in the Callbacks module.
-  #
-  # == Storing Observers in Rails
-  #
-  # If you're using Active Record within Rails, observer classes are usually stored in app/models with the
-  # naming convention of app/models/audit_observer.rb.
-  #
-  # == Configuration
-  #
-  # In order to activate an observer, list it in the <tt>config.active_record.observers</tt> configuration
-  # setting in your <tt>config/application.rb</tt> file.
-  #
-  #   config.active_record.observers = :comment_observer, :signup_observer
-  #
-  # Observers will not be invoked unless you define these in your application configuration.
-  #
-  # If you are using Active Record outside Rails, activate the observers explicitly in a configuration or
-  # environment file:
-  #
-  #   ActiveRecord::Base.add_observer CommentObserver.instance
-  #   ActiveRecord::Base.add_observer SignupObserver.instance
-  #
-  # == Loading
-  #
-  # Observers register themselves in the model class they observe, since it is the class that
-  # notifies them of events when they occur. As a side-effect, when an observer is loaded its
-  # corresponding model class is loaded.
-  #
-  # Up to (and including) Rails 2.0.2 observers were instantiated between plugins and
-  # application initializers. Now observers are loaded after application initializers,
-  # so observed models can make use of extensions.
-  #
-  # If by any chance you are using observed models in the initialization you can still
-  # load their observers by calling <tt>ModelObserver.instance</tt> before. Observers are
-  # singletons and that call instantiates and registers them.
-  #
-  class Observer < ActiveModel::Observer
-
-    protected
-
-      def observed_classes
-        klasses = super
-        klasses + klasses.map { |klass| klass.descendants }.flatten
-      end
-
-      def add_observer!(klass)
-        super
-        define_callbacks klass
-      end
-
-      def define_callbacks(klass)
-        observer = self
-        observer_name = observer.class.name.underscore.gsub('/', '__')
-
-        ActiveRecord::Callbacks::CALLBACKS.each do |callback|
-          next unless respond_to?(callback)
-          callback_meth = :"_notify_#{observer_name}_for_#{callback}"
-          unless klass.respond_to?(callback_meth)
-            klass.send(:define_method, callback_meth) do |&block|
-              observer.update(callback, self, &block)
-            end
-            klass.send(callback, callback_meth)
-          end
-        end
-      end
-  end
-end
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb
index eed49e17b1..81e56a3e2e 100644
--- a/activerecord/lib/active_record/persistence.rb
+++ b/activerecord/lib/active_record/persistence.rb
@@ -102,7 +102,7 @@ module ActiveRecord
     # record's primary key, and no callbacks are executed.
     #
     # To enforce the object's +before_destroy+ and +after_destroy+
-    # callbacks, Observer methods, or any <tt>:dependent</tt> association
+    # callbacks or any <tt>:dependent</tt> association
     # options, use <tt>#destroy</tt>.
     def delete
       self.class.delete(id) if persisted?
diff --git a/activerecord/lib/active_record/railtie.rb b/activerecord/lib/active_record/railtie.rb
index a73473f59c..624d2784e8 100644
--- a/activerecord/lib/active_record/railtie.rb
+++ b/activerecord/lib/active_record/railtie.rb
@@ -168,15 +168,5 @@ module ActiveRecord
       path = app.paths["db"].first
       config.watchable_files.concat ["#{path}/schema.rb", "#{path}/structure.sql"]
     end
-
-    config.after_initialize do |app|
-      ActiveSupport.on_load(:active_record) do
-        instantiate_observers
-
-        ActionDispatch::Reloader.to_prepare do
-          ActiveRecord::Base.instantiate_observers
-        end
-      end
-    end
   end
 end
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index f0f170b684..0df895eb67 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -315,11 +315,9 @@ module ActiveRecord
 
     # Destroys the records matching +conditions+ by instantiating each
     # record and calling its +destroy+ method. Each object's callbacks are
-    # executed (including <tt>:dependent</tt> association options and
-    # +before_destroy+/+after_destroy+ Observer methods). Returns the
+    # executed (including <tt>:dependent</tt> association options). Returns the
     # collection of objects that were destroyed; each will be frozen, to
-    # reflect that no changes should be made (since they can't be
-    # persisted).
+    # reflect that no changes should be made (since they can't be persisted).
     #
     # Note: Instantiation, callback execution, and deletion of each
     # record can be time consuming when you're removing many records at
@@ -419,8 +417,7 @@ module ActiveRecord
     # Deletes the row with a primary key matching the +id+ argument, using a
     # SQL +DELETE+ statement, and returns the number of rows deleted. Active
     # Record objects are not instantiated, so the object's callbacks are not
-    # executed, including any <tt>:dependent</tt> association options or
-    # Observer methods.
+    # executed, including any <tt>:dependent</tt> association options.
     #
     # You can delete multiple rows at once by passing an Array of <tt>id</tt>s.
     #