This is what you do after you casually upgrade paperclip from v2.x to v4.x and w/o noticing the default paths changed…

gistfile1.txt

s3 = AWS::S3.new
bucket = s3.buckets['trooptrack-prod']
no_doc = []
done_it = []

Event.where('attachment_file_name is not null').
  find_each do |thing|

  old_key = "attachments/#{thing.id}/original/#{thing.attachment_file_name}"
  new_key = thing.attachment.path
  new_key[0] = ''
  begin
    obj = bucket.objects[old_key]
    obj.copy_to(new_key)
    done_it << thing.id
  rescue AWS::S3::Errors::NoSuchKey
    no_doc << thing.id
  end
end