Delayed Job Singleton

delayed_singleton.rb

module DelayedSingleton

  # this first checks whether the same job has already been enqueued.
  # if not, it enqueues it to run in one minute
  def enqueue_singleton job, at = 1.minute.from_now
    unless Delayed::Job.where(:handler => job.to_yaml).any?
      Rails.logger.warn "enqueuing singleton job #{job.class.name}"
      Delayed::Job.enqueue(job, run_at: at.getutc )
    end
  end
end