# Active Job -- Make work happen later
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.
## Usage
Set the queue adapter for Active Job:
``` ruby
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:
```ruby
class MyJob < ActiveJob::Base
queue_as :my_jobs
def perform(record)
record.do_work
end
end
```
Enqueue a job like so:
```ruby
MyJob.enqueue record # Enqueue a job to be performed as soon the queueing system is free.
```
```ruby
MyJob.enqueue_at Date.tomorrow.noon, record # Enqueue a job to be performed tomorrow at noon.
```
```ruby
MyJob.enqueue_in 1.week, record # Enqueue a job to be performed 1 week from now.
```
That's it!
## GlobalID support
Active Job supports [GlobalID serialization](https://github.com/rails/globalid/) 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:
```ruby
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:
```ruby
class TrashableCleanupJob
def perform(trashable, depth)
trashable.cleanup(depth)
end
end
```
This works with any class that mixes in GlobalID::Identification, which
by default has been mixed into Active Record classes.
## Supported queueing systems
We currently have adapters for:
* [Backburner](https://github.com/nesquena/backburner)
* [Delayed Job](https://github.com/collectiveidea/delayed_job)
* [Qu](https://github.com/bkeepers/qu)
* [Que](https://github.com/chanks/que)
* [QueueClassic](https://github.com/ryandotsmith/queue_classic)
* [Resque 1.x](https://github.com/resque/resque)
* [Sidekiq](https://github.com/mperham/sidekiq)
* [Sneakers](https://github.com/jondot/sneakers)
* [Sucker Punch](https://github.com/brandonhilkert/sucker_punch)
## Auxiliary gems
* [activejob-stats](https://github.com/seuros/activejob-stats)
## Download and installation
The latest version of Active Job can be installed with RubyGems:
```
% [sudo] gem install activejob
```
Source code can be downloaded as part of the Rails project on GitHub
* https://github.com/rails/rails/tree/master/activejob
## License
ActiveJob is released under the MIT license:
* http://www.opensource.org/licenses/MIT
## Support
API documentation is at
* http://api.rubyonrails.org
Bug reports can be filed for the Ruby on Rails project here:
* https://github.com/rails/rails/issues
Feature requests should be discussed on the rails-core mailing list here:
* https://groups.google.com/forum/?fromgroups#!forum/rubyonrails-core