Active Job is a framework for declaring jobs and making them run on a variety of queueing backends. These jobs can be everything from regularly scheduled clean-ups, billing charges, or mailings. Anything that can be chopped up into small units of work and run in parallel, really.
It also serves as the backend for ActionMailer's #deliver_later functionality that makes it easy to turn any mailing into a job for running later. That's one of the most common jobs in a modern web application: Sending emails outside of the request-response cycle, so the user doesn't have to wait on it.
The main point is to ensure that all Rails apps will have a job infrastructure in place, even if it's in the form of an "immediate runner". We can then have framework features and other gems build on top of that, without having to worry about API differences between Delayed Job and Resque. Picking your queuing backend becomes more of an operational concern, then. And you'll be able to switch between them without having to rewrite your jobs.
Set the queue adapter for Active Job:
ActiveJob::Base.queue_adapter = :inline # default queue adapter
# Adapters currently supported: :backburner, :delayed_job, :qu, :que, :queue_classic,
# :resque, :sidekiq, :sneakers, :sucker_punch
Declare a job like so:
class MyJob < ActiveJob::Base
queue_as :my_jobs
def perform(record)
record.do_work
end
end
Enqueue a job like so:
MyJob.enqueue record # Enqueue a job to be performed as soon the queueing system is free.
MyJob.enqueue_at Date.tomorrow.noon, record # Enqueue a job to be performed tomorrow at noon.
MyJob.enqueue_in 1.week, record # Enqueue a job to be performed 1 week from now.
That's it!
Active Job supports GlobalID serialization for parameters. This makes it possible to pass live Active Record objects to your job instead of class/id pairs, which you then have to manually deserialize. Before, jobs would look like this:
class TrashableCleanupJob
def perform(trashable_class, trashable_id, depth)
trashable = trashable_class.constantize.find(trashable_id)
trashable.cleanup(depth)
end
end
Now you can simply do:
class TrashableCleanupJob
def perform(trashable, depth)
trashable.cleanup(depth)
end
end
This works with any class that mixes in ActiveModel::GlobalIdentification, which by default has been mixed into Active Record classes.
We currently have adapters for:
Active Job is currently being developed in a separate repository until it's ready to be merged in with Rails. The current plan is to have Active Job be part of the Rails 4.2 release, but plans may change depending on when this framework stabilizes and feels ready.
Active Job is released under the MIT license: