paperclip run processors on selected style

Question

I have an :xxx image processor, and I have two styles in the model :big and :thumb.

How I can process with :xxx only the :thumb image leaving the :big image untouched ?

Answer 1

I recently had a similar problem and found this solution on a message board. Hope it helps!

has_attached_file :screenshot,
 :default_style => :full,
 :styles => {
   :full => "280x210",
   :cropped => { :processors => [:screenshot_crop] }
 }

Answer 2

By default, the Rake task refreshes all thumbnails. Keep in mind that it won't touch / process the original image.

You could have a look at the Rakefile and the Attachment class and modify to allow you to specify a specific thumbnail size, but the current design assumes that you want to take the original and redo all thumbnails from the original.

Answer 3

Add this code to your paperclip.rake file:

   desc "Reprocesses your attachments style (set CLASS, ATTACHMENT and STYLE)"
    task :style => :environment do
      module JustForOneDay
        NAME = ENV['STYLE']
      end

      module ::Paperclip
        class Attachment
          def post_process_styles #:nodoc:
            @styles.each do |name, args|
              if JustForOneDay::NAME == name
                begin
                  raise RuntimeError.new("Style #{name} has no processors defined.") if args[:processors].blank?
                  @queued_for_write[name] = args[:processors].inject(@queued_for_write[:original]) do |file, processor|
                    Paperclip.processor(processor).make(file, args, self)
                  end
                rescue PaperclipError => e
                  log("An error was received while processing: #{e.inspect}")
                  (@errors[:processing] ||= []) << e.message if @whiny
                end
              end
            end
          end
        end
      end

      for_all_attachments do |instance, name|
        result = instance.send(name).reprocess!
      end
    end
  end

Tested with Paperclip 2.3.1.1

In Paperclip 2.3.3 this should be:

def post_process_styles #:nodoc:
  styles.each do |name, style|
    if JustForOneDay::NAME == name
    begin
      raise RuntimeError.new("Style #{name} has no processors defined.") if style.processors.blank?
      @queued_for_write[name] = style.processors.inject(@queued_for_write[:original]) do |file, processor|
        Paperclip.processor(processor).make(file, style.processor_options, self)
      end
    rescue PaperclipError => e
      log("An error was received while processing: #{e.inspect}")
      (@errors[:processing] ||= []) << e.message if @whiny
    end
    end
  end
end

It's easy, just go to attachment.rb file in your paperclip version.