Dragonfly image processor

GenerateImageThumbnailsJob.rb

class GenerateImageThumbnailsJob < Struct.new(:photo_id)

  def perform
    photo = Photo.find(photo_id)
    photo.medium_image = photo.image.thumb('940x600')
    photo.large_image = photo.image.thumb('450x')
    photo.small_image = photo.image.thumb('172x167#c')
    photo.save
  end

  def success(job)
    puts ">>> Successful finished job: #{job.id}"
  end

  def failure(job)
    puts ">>> Job #{job.id} failed to resize image"
  end

end

rake.rb

namespace :data do
  task :photos => :environment do
    Photo.select("id").where(:medium_image_uid => nil).find_in_batches do |photos|
      photos.each do |photo|
        Delayed::Job.enqueue GenerateImageThumbnailsJob.new(photo.id)
      end
    end
  end
end