133165106b
Change-Id: I61d5ba9f6ef5e0837da2ec22b695b9a56b88acb5 Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/293104 Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com> Reviewed-by: August Thornton <august@instructure.com> Reviewed-by: Alex Slaughter <aslaughter@instructure.com> QA-Review: Jacob Burroughs <jburroughs@instructure.com> Product-Review: Jacob Burroughs <jburroughs@instructure.com> |
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| .. | ||
| lib/active_support/callbacks | ||
| spec | ||
| .rspec | ||
| Gemfile | ||
| LICENSE.txt | ||
| README.md | ||
| Rakefile | ||
| activesupport-suspend_callbacks.gemspec | ||
| test.sh | ||
README.md
Suspend Callbacks
ActiveSupport's Callbacks module allows you to define a callback hook and then register methods to be run before/after/around that hook.
It also let's you skip callbacks in a specific context. For example, ActiveRecord::Base defines a callback hook around save. My top level Person model may register an :ensure_privacy method to run before save. But the Celebrity model that inherits from Person can then skip that callback. End result: when I save a john_doe Person object, :ensure_privacy will run, but when I save the dhh Celebrity object, it won't.
But what if you want to suspend callbacks, regardless of subclass, but only for a duration of time? That's when you want to suspend callbacks.
Example
class MyModel < ActiveRecord::Base include ActiveSupport::Callbacks::Suspension
before :save, :expensive_callback after :save, :other_callback
def expensive_callback # stuff end
def other_callback # stuff end end
instance1 = MyModel.new instance2 = MyModel.new
MyModel.suspend_callbacks do
neither callback will run for either instance
instance1.save instance2.save end
MyModel.suspend_callbacks(kind: :save) do
same
instance1.save instance2.save end
MyModel.suspend_callbacks(:expensive_callback) do
expensive_callback won't run, but other_callback will
instance1.save instance2.save end
MyModel.suspend_callbacks(type: :before) do
same
instance1.save instance2.save end
instance1.suspend_callbacks do
callbacks won't run this time...
instance1.save
... but they will this time.
instance2.save end