Rails 3 - Delayed_Job

Question

I'm working to learn how to user delayed_job on my rails 3 + heroku app.

I currently have the following which emails on a request (not delayed job) but it works!

UserMailer.conversation_notification(record.commentable, participant, record, @comments).deliver

I updated that to this to start using delayed_job:

Delayed::Job.enqueue UserMailer.conversation_notification(record.commentable, participant, record, @comments).deliver

But that error'd with: "ArgumentError (Cannot enqueue items which do not respond to perform):"

I also tried:

UserMailer.delay.conversation_notification(record.commentable, participant, record, @comments)

But that error'd with:

NoMethodError (undefined method `delay' for UserMailer:Class):

Any delayed_job guru's out there? Thanks

Answer 1

From the docs https://github.com/collectiveidea/delayed_job

Your second method was correct which removes the .deliver method:

UserMailer.delay.conversation_notification(record.commentable, participant, record, @comments)

If you are getting an undefined method delay did you add DelayedJob to the Gemfile?

gem "delayed_job"

Since including the delayed_job will add the "delay" method to everything.

Answer 2

I have mixed results with using delay, and I've found it very challenging to debug. So you are not alone! But when you get it working, its worth it.

I've learned to save my object before calling delay on it. Typically I will trigger my job from an after_save call back.

As an experiment, for awhile I was using a different pattern. I'd create a job object for each job that I have. For example, I would call

Delayed::Job.enqueue(PersonJob.new(@person.id))

Elsewhere in my project I would create the job object. In Rails 2, I put these in lib/ if you do that with rails 3, you need to alter the application.rb config.autload_path

class PersonJob < Struct.new(:person_id)
  def perform
    person = Person.find(person_id)
    #do work
  end
end


config.autoload_paths += Dir["#{config.root}/lib/**/"]

Answer 3

I just had a look at the documentation, it's been a while since I actually used delayed_job...

Jobs are Ruby objects with a method called perform , so you'd need enqueue an object which does

UserMailer.conversation_notification(record.commentable, participant, record, @comments).deliver

in its perform method.

Alternatively, you can use send_later :

UserMailer.conversation_notification(record.commentable, participant, record, @comments).send_later(:deliver)