Feature Request: Add GUI for Duplicity WebDAV Backend

[elsiehupp]

Duplicity natively supports WebDAV, but currently Mail-in-a-Box does not implement this.

WebDAV is useful because many users of Mail-in-a-Box also use Nextcloud, and Nextcloud provides a more user-friendly abstraction layer.

Also, for users with Nextcloud managed hosting, being able to use Nextcloud directly saves on costs by not requiring, e.g., S3, which on, e.g., DigitalOcean has a base price of $10/month, substantially more than the base price of a Mail-in-a-Box VPS, which is currently $6/month. Being able to back up my Mail-in-a-Box to Nextcloud would, then, save me, personally, something like $10-11/month, which really adds up!

Resources:

• Duplicity Python API for WebDAV
• Duplicity Command Line API (does not have a top-level section for WebDAV backend but describes syntax)

As an aside: support for the Nextcloud Flow API would be nice, but I imagine that would have to be added by Duplicity before it would be added to Mail-in-a-Box.

[elsiehupp]

I just checked, and there is an issue on the Duplicity repo discussing Nextcloud support which was closed because Nextcloud is supported through rclone. So I suppose direct support for, e.g., Nextcloud could be added through Duplicity's implementation of rclone. rclone does not seem to support the Nextcloud Flow API as of yet, so I suppose I should go open an issue with them asking them to implement it.