How it Works ============ After a file is backed up in Glacier, a reference is stored in a local database. This can be used for future retrievals with the command ``request_file``. After this is done, a job is created in glacier (lasting aprox 4 hours), when this job is completed, AWS sends a request to our sns endpoint (``run_sns_listener``) previously configured on AWS dashboard. Our listener receives the AWS response, and then proceeds to download the file.