Migrating paperclip attachments from file storage to s3 storage

migrate.rb

require 'aws-sdk'
require 'bcdatabase'
config = Bcdatabase.load[:secrets, :paperclip_s3]
AWS.config(config)

BUCKET = AWS::S3.new.buckets[config['bucket']]

require 'find'

Find.find('public/system/') { |f|
  unless f.match(/\/\..+$/) || File.directory?(f)
    name = f.split('public/system/')[1]
    puts name
    File.open(f, 'r') do |r|
      BUCKET.objects[name].write(r.read, acl: :public_read)
    end
  end
}

script

 BUNDLE_GEMFILE=../releases/2014..../Gemfile bundle exec ruby migrate.rb

# Put 'migrate.rb' in your shared_path and run the above command from there
# The trick is to run this while capistrano is still deploying, as soon as bundle install is complete, before the deploy:restart task
# That way, by the time the application restarts, your files have all been copied (assuming this script is shorter than the rest of your deployment)