.cache/kopia isn't fully tagged with CACHEDIR.TAG

[Juerd]

Kopia will put a CACHEDIR.TAG file in a blob cache to facilitate skipping its own directory when creating a snapshot, but the file is not present in the base of the cache directory (e.g. ~/.cache/kopia), which results in backups of cli-logs, content-logs and <hash>/server-contents. While I feel that none of these should be backed up by default, at least the server-contents cache should probably be treated the same way as the blob cache, because it is large and redundant with the contents of the backup itself.

[jkowalski]

+1. That should be a quick and easy fix. PR welcome.

[israel-lugo]

I just recently started using Kopia, and was surprised to see that --ignore-cache-dirs doesn't make Kopia ignore its own cache.

I'm much more worried about the /server-contents than the logs; on the first machine I looked at, server-contents is over 1 GiB. Logs themselves, I don't see why they shouldn't be backed up (although it's weird that they're stored in a cache directory). But server-contents really shouldn't be.

Could someone please take a second look at the PR or create a new one?