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diff --git a/guides/source/active_job_basics.md b/guides/source/active_job_basics.md index 9c34418fab..4d1625b28d 100644 --- a/guides/source/active_job_basics.md +++ b/guides/source/active_job_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** + Active Job Basics ================= @@ -23,7 +25,7 @@ clean-ups, to billing charges, to mailings. Anything that can be chopped up into small units of work and run in parallel, really. -The Purpose of the Active Job +The Purpose of Active Job ----------------------------- 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 @@ -41,10 +43,12 @@ This section will provide a step-by-step guide to creating a job and enqueuing i ### Create the Job Active Job provides a Rails generator to create jobs. The following will create a -job in `app/jobs`: +job in `app/jobs` (with an attached test case under `test/jobs`): ```bash $ bin/rails generate job guests_cleanup +invoke test_unit +create test/jobs/guests_cleanup_job_test.rb create app/jobs/guests_cleanup_job.rb ``` @@ -52,12 +56,8 @@ You can also create a job that will run on a specific queue: ```bash $ bin/rails generate job guests_cleanup --queue urgent -create app/jobs/guests_cleanup_job.rb ``` -As you can see, you can generate jobs just like you use other generators with -Rails. - If you don't want to use a generator, you could create your own file inside of `app/jobs`, just make sure that it inherits from `ActiveJob::Base`. @@ -78,15 +78,19 @@ end Enqueue a job like so: ```ruby -MyJob.perform_later record # Enqueue a job to be performed as soon the queueing system is free. +# Enqueue a job to be performed as soon the queueing system is +# free. +MyJob.perform_later record ``` ```ruby -MyJob.set(wait_until: Date.tomorrow.noon).perform_later(record) # Enqueue a job to be performed tomorrow at noon. +# Enqueue a job to be performed tomorrow at noon. +MyJob.set(wait_until: Date.tomorrow.noon).perform_later(record) ``` ```ruby -MyJob.set(wait: 1.week).perform_later(record) # Enqueue a job to be performed 1 week from now. +# Enqueue a job to be performed 1 week from now. +MyJob.set(wait: 1.week).perform_later(record) ``` That's it! @@ -103,14 +107,20 @@ Active Job has built-in adapters for multiple queueing backends (Sidekiq, Resque, Delayed Job and others). To get an up-to-date list of the adapters see the API Documentation for [ActiveJob::QueueAdapters](http://api.rubyonrails.org/classes/ActiveJob/QueueAdapters.html). -### Changing the Backend +### Setting the Backend -You can easily change your queueing backend: +You can easily set your queueing backend: ```ruby -# be sure to have the adapter gem in your Gemfile and follow the adapter specific -# installation and deployment instructions -Rails.application.config.active_job.queue_adapter = :sidekiq +# config/application.rb +module YourApp + class Application < Rails::Application + # Be sure to have the adapter's gem in your Gemfile + # and follow the adapter's specific installation + # and deployment instructions. + config.active_job.queue_adapter = :sidekiq + end +end ``` @@ -145,19 +155,42 @@ class GuestsCleanupJob < ActiveJob::Base end # Now your job will run on queue production_low_priority on your -# production environment and on beta_low_priority on your beta -# environment +# production environment and on staging_low_priority +# on your staging environment +``` + +The default queue name prefix delimiter is '\_'. This can be changed by setting +`config.active_job.queue_name_delimiter` in `application.rb`: + +```ruby +# config/application.rb +module YourApp + class Application < Rails::Application + config.active_job.queue_name_prefix = Rails.env + config.active_job.queue_name_delimiter = '.' + end +end + +# app/jobs/guests_cleanup.rb +class GuestsCleanupJob < ActiveJob::Base + queue_as :low_priority + #.... +end + +# Now your job will run on queue production.low_priority on your +# production environment and on staging.low_priority +# on your staging environment ``` -If you want more control on what queue a job will be run you can pass a :queue -option to #set: +If you want more control on what queue a job will be run you can pass a `:queue` +option to `#set`: ```ruby MyJob.set(queue: :another_queue).perform_later(record) ``` -To control the queue from the job level you can pass a block to queue_as. The -block will be executed in the job context (so you can access self.arguments) +To control the queue from the job level you can pass a block to `#queue_as`. The +block will be executed in the job context (so you can access `self.arguments`) and you must return the queue name: ```ruby @@ -179,7 +212,6 @@ end ProcessVideoJob.perform_later(Video.last) ``` - NOTE: Make sure your queueing backend "listens" on your queue name. For some backends you need to specify the queues to listen to. @@ -187,8 +219,8 @@ backends you need to specify the queues to listen to. Callbacks --------- -Active Job provides hooks during the lifecycle of a job. Callbacks allow you to -trigger logic during the lifecycle of a job. +Active Job provides hooks during the life cycle of a job. Callbacks allow you to +trigger logic during the life cycle of a job. ### Available callbacks @@ -222,7 +254,7 @@ end ``` -ActionMailer +Action Mailer ------------ One of the most common jobs in a modern web application is sending emails outside @@ -240,12 +272,13 @@ UserMailer.welcome(@user).deliver_later GlobalID -------- + Active Job supports 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 +class TrashableCleanupJob < ActiveJob::Base def perform(trashable_class, trashable_id, depth) trashable = trashable_class.constantize.find(trashable_id) trashable.cleanup(depth) @@ -256,15 +289,15 @@ end Now you can simply do: ```ruby -class TrashableCleanupJob +class TrashableCleanupJob < ActiveJob::Base 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 Model classes. +This works with any class that mixes in `GlobalID::Identification`, which +by default has been mixed into Active Record classes. Exceptions @@ -274,7 +307,6 @@ Active Job provides a way to catch exceptions raised during the execution of the job: ```ruby - class GuestsCleanupJob < ActiveJob::Base queue_as :default |