add command do delete orphan shares

[icewind1991]

Compared to the existing background job, this command validates that the share owner still has access to the file instead of just checking that the file still exists.

I've decided against not adding this to the background command as the "owner lost access" case is recoverable by having the owner regain access. So automatically deleting them might be undesired.

Steps to create an orphaned share:

• Setup user A, B and C. Create a groupfolder G and give A and B access to it.
• User B uploads a file F to G and shares it with C
• User A moves F outside G
• C now has an orphaned share as B no longer has access to F

[AndyScherzinger]

/backport to stable27

[AndyScherzinger]

/backport to stable26

[artonge]

• Does it really scale to fetch all share and then to set up the file system for each owner? Or does the yield statement makes it more manageable? Not familiar with it.
• Do we have a logic in place to prevent those from happening?

[artonge]

No option to delete them one by one? Maybe it is irrelevant in the use case.

[icewind1991]

Does it really scale to fetch all share and then to set up the file system for each owner? Or does the yield statement makes it more manageable? Not familiar with it.

It will be slow yes, but there isn't really to much that can be done for that

[AndyScherzinger]

If it only makes the command slow then I'd say that is fine or would it also impact "online" transactions? 👍

[icewind1991]

Performance impact is only for the command

[backportbot-nextcloud]

The backport to stable26 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable26
git pull origin stable26

# Create the new backport branch
git checkout -b fix/foo-stable26

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts. Resolve them.
git cherry-pick abc123

# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable26

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport

[ChristophWurst]

The new occ command needs admin docs

[Rello]

nextcloud/documentation#11443