Transfer PaperClip attachment files from S3 to the filesystem

s3_transfer.rb

@base = File.join(Rails.root, "public/system/attachments/#{Rails.env}/")
# model: Class
# method: :symbol
# eg transfer(Image, :file)
def transfer(model, method)
  dummy = model.new.send(method)
  styles = [nil] + dummy.styles.keys
  
  model.all.each do |obj|
    styles.each do |style|

      cur = obj.send(method)

      FileUtils.mkdir_p(File.join(@base, cur.path(style)).gsub(/\/[^\/]*?$/, ''))
      f = File.open(File.join(@base, cur.path(style)), 'w')
      begin
      f.write(cur.to_file(style).read)
      f.close
      rescue; 0; end
    end
  end
  
end