allow to exclude previews from backup upon instance backup

[devnoname120]

Follow up of: #5550

@szaimen I haven't tested the changes yet as I don't have the right setup… Is there any chance you could test them? Thanks!

[devnoname120]

Edit: I added Signed-off-by: Paul <[email protected]> to the end of the commit message and then force-pushed to make DCO pass.

[devnoname120]

@szaimen Is there a way to test the changes on my side on my production instance? I tried looking into building the whole AIO thing but there doesn't seem to be an easy way to do that. The actual docker build pipeline seem to be defined in the nextcloud-releases repo: https://github.com/nextcloud-releases/all-in-one/blob/main/.github/workflows/build_images.yml

I vaguely tried to pull the CI workflow change it to push to ghcr.io (to my own fork) instead of docker.io but the references to docker.io look farther reaching than just in the CI pipelines so I quickly gave up…

[szaimen]

Hi @devnoname120 thanks a lot for the contribution and sorry for my late reply!

I unfortunately have some problems with this as in my opinion, the backup should always represent a full backup with intact database and file system and basically including all data needed to restore the same state without exception. This also includes the previews as their path is also written into the database. Allowing to exclude the previews means that we always need to scan the database upon restore which is hacky imho.

Also, maybe we could find a better way that allows to exclude previews and more without having to add an option to the interface for each thing? This could probably be implemented like this: #4751. Would you be able to work on this?

Please let me know what you think about my thoughts!