Is there a way to add a callback to a failed attempt in Delayed::Job?

Occasion开发者_StackOverflow社区ally a job will increment an attempt and not perform the method regenerate_styles. I've noticed that if I pass a method rengerate_styles manually to whatever the failed job is - 100% of the time always fixes the problem.

So if the image is not processing, and I pass :

Photo.find(image).regenerate_styles!

It works as expected.

Is it possible to write a callback that detects a failed attempt, and runs a method? Or is there something in this code distinguishing to why it would not be processing some of the time.

the model

after_save do |image|
  if image.source_changed?
    Delayed::Job.enqueue PhotoJob.new(image.id)
  end
end

def regenerate_styles!
  self.photo.reprocess!
  self.processing = false
  self.save(false)
end

the photojob

class PhotoJob < Struct.new(:image_id)
  def perform
    Photo.find(self.image_id).regenerate_styles!
  end
end

Starting from DelayedJob 2.1 there is an hook called :error. Just define a method called error in your job definition.

def error(job, error)
  # do whatever you want here
end