Methods to build a Rake task to convert attachment_fu file store images to the Rackspace cloud

Convert File Storage to Cloud Storage.rb

# New Model with Cloudfiles Storage
class Photo < ActiveRecord::Base
  has_attachment :content_type => :image,
                 :max_size => 1.megabyte,
                 :storage => :cloud_files,
                 :resize_to => "fill 128x128"
end

# Old Model with overwritten attachment methods
class OldPhoto < Photo
  has_attachment :content_type => :image,
                 :max_size => 1.megabyte,
                 :storage => :file_system,
                 :resize_to => "fill 128x128"
end

# Method to check that a URL exists - confirms that a Cloudfile was uploaded successfully
require 'net/http'
def is_active_url(url)
  begin
      case Net::HTTP.get_response(URI.parse(url))
        when Net::HTTPSuccess then true
        else false
      end
  rescue
      false
  end
end

# Convert method
require 'action_controller'
require 'action_controller/test_process.rb'
def convert(old, new)
  if File.exists?(old.full_filename)
    new.uploaded_data = ActionController::TestUploadedFile.new(old.full_filename, old.content_type)
    new.save
    puts "+++ Converted #{new.class.to_s} #{old.id}, it is located at #{new.public_filename}"
    if is_active_url(new.public_filename)
      File.delete(old.full_filename)
      puts "     - #{new.public_filename} Exists, Deleted #{old.full_filename}"
    end
  else
    puts "--- No need to convert #{new.class.to_s} #{old.id}, it is located at #{new.public_filename}"
  end
end

# Final composed Rake Task
namespace :convert do
  desc 'Convert Filestore Image to Cloud File Storage'

  task :photos => :environment do
    class OldPhoto < Photo
      has_attachment :content_type => :image,
                     :max_size => 1.megabyte,
                     :storage => :file_system,
                     :resize_to => "fill 128x128"
    end  

    puts "Attempting to convert #{OldPhoto.all.count} Photos"
    OldPhoto.all.each do |old|
      new = Photo.find(old.id)
      convert(old, new)
    end
  end
end