Rails Jobs

about.md

Important notes

1. Use ActiveJob
2. Use different adapters: Sidekiq, Resque
3. Backend adapters depend on workers to execute jobs
4. Use queues for different kind of jobs / tasks: mailing, maintenance, etc.
5. Job perform callbacks are available as well
6. ActionMailer can work as an ActiveJob
7. Watch out for Thread safety - pay attention to instance variables and how they are accessed and changed in concurrent processes. One option is to use Mutex
8. Sidekiq > Resque > DelayedJob (But it depends on the needs and available resources)

Links to read

ActiveJob Basics Testing ActiveJob

Creating ActiveJob in Rails

rails generate job job_name --queue job_queue

Queue job

TestJob.perform_later(args)
TestJob.set(wait_until: Date.tomorrow.noon).perform_later(args)
TestJob.set(wait: 1.week).perform_later(args)
TestJob.perform_later(arg1, arg2, filter: 'some_filter')

ActionMailer

ActionMailer can work as ActiveJob. To send mails as a job (user won't have to wait):

UserMailer.welcome(@user).deliver_now
 vs
UserMailer.welcome(@user).deliver_later