The structure of the custom.yaml file has been modified in order to simplify
the reading and maintainability of the backup.py code and definitively fix
problems related to backups on S3-compatible services not provided by AWS.
In addition to improved code readability, it is now verified that backup
also works on MinIO, solving issue #717.
For users who have been using mail-in-a-box from before version v60
and who do not need the region parameter in duplicity configuration,
the backup continues to work without impacts.
The region value used for backups on S3-compatible services
is now saved correctly even if the user changes the configuration
from backup of type S3 to another.
Starting from the versions subsequent to the v57a, the default backend
of duplicity for backups to S3-compatible services is boto3
which requires the indication of the region (--S3-region-name)
for most cases in which the S3 service is not provided by AWS.
Thanks to this intervention, the region of the S3 service
is provided as a parameter to duplicity and is stored in the
/home/user-data/backup/custom.yaml file, like any other backup
configuration parameters.
Moreover, the list of the regions shown to the user in the drop-down
menu in the backup configuration panel is replaced with
a normal text field, since the list included the AWS regions only
and therefore was not usable in all other cases.
See issue #2200.