How can I migrate CarrierWave files to a new storage mechanism?

Question

I have a Ruby on Rails site with models using CarrierWave for file handling, currently using local storage. I want to start using cloud storage and I need to migrate existing lo

Answer 1

When we use Heroku, most of people suggest to use cloudinary. Free and simple setup. My case is when we use cloudinary service and need move into aws S3 for some reasons.

This is what i did with the uploader:

class AvatarUploader < CarrierWave::Uploader::Base

  def self.set_storage
    if ENV['UPLOADER_SERVICE'] == 'aws'
      :fog
    else
      nil
    end
  end

  if ENV['UPLOADER_SERVICE'] == 'aws'
     include CarrierWave::MiniMagick
  else
     include Cloudinary::CarrierWave
  end

  storage set_storage
end

also, setup the rake task:

task :migrate_cloudinary_to_aws do
    profile_image_old_url = []
    Profile.where("picture IS NOT NULL").each do |profile_image|
      profile_image_old_url << profile_image
    end

   ENV['UPLOADER_SERVICE'] = 'aws'
   load("#{Rails.root}/app/uploaders/avatar_uploader.rb")

   Profile.where("picture IS NOT NULL OR cover IS NOT NULL").each do |profile_image|
     old_profile_image = profile_image_old_url.detect { |image| image.id == profile_image.id }
     profile_image.remote_picture_url = old_profile_image.picture.url
     profile_image.save
   end
end

The trick is how to change the uploader provider by env variable. Good luck!