Unify/cleanup filesystem setup

[icewind1991]

• Moves filesystem setup logic from static OC_Util/OC\Files\Filesystem functions to it's own class
• New setup logic is called from all the relevant old places for compatibility
• Includes a fair number of changes to unit tests since they tend to do a lot of weird things with the filesystem

Requires

• Move root mount setup to mountprovider move root mount setup to mountproviders #31266

Part of #31265

[PVince81]

👍 overall it looks fine, see minor comments

[PVince81]

does it make sense to also have a tear down for a single user or is it too complicated ?

use case could be when running bkg jobs that iterate over lots of users and needs the FS

or as a middle group, one that only tears down the users, not the root ? (but root setup is likely cheap, isn't it?

[icewind1991]

Root setup is generally cheap yes so I'm not sure if there is much to gain there.

Additionally, background jobs can probably be adjusted to not teardown the filesystem but instead setup for an additional user

[danxuliu]

Since 22875bf the integration tests in Talk fail.

When a conversation is associated to a file (a conversation opened in the Chat tab in the Files app) and a participant gets the possible mentions the list includes the current participants of the conversation as well as other users with access to that file but that are not in the conversation yet.

To do that the node for the file id is got using $this->rootFolder->getById($fileId). The path of the root node is empty (''), so with the previous code this call ended setting up the full filesystem for the user and finding the node. However, with the new code (due to the substr_count($path, '/') < 2 check) only the root filesystem is set up, the node is not found and the list of other users with access to the file ends being empty.

If $this->rootFolder->getById($fileId) is replaced by if ($this->userId) { $userFolder = $this->rootFolder->getUserFolder($this->userId); $nodes = $userFolder->getById($fileId); } in Talk then everything works again.

@icewind1991 Should that be changed in Talk because the code is wrong and it just happened to work until now? Or is the code in Talk fine and it is a regression that should be fixed in the server?

Thanks!

[icewind1991]

@danxuliu can you check if #31598 helps

[danxuliu]

@danxuliu can you check if #31598 helps

Yes, the failing tests pass again with #31598. Thanks!

[jotoeri]

Similar thing on forms - Unittests fail on tearDown with server masterbranch. Seems to me to be connected to this PR? And still consists after the mentioned PR...

Do you have any idea on this, @icewind1991?

Exception in OCA\Forms\Tests\Unit\Activity\ActivityManagerTest::tearDownAfterClass
Argument 1 passed to OC\Files\Config\UserMountCache::__construct() must implement interface OCP\IDBConnection, null given, called in /home/runner/work/forms/forms/lib/private/Server.php on line 935

https://github.com/nextcloud/forms/runs/5618838041

[artonge]

@icewind1991 The throw should be highlighted in #37039 as it change how you would use the API.
Already got bitten in activity: nextcloud/activity#1165

[artonge]

Issue happened only after @come-nc cleanup in View.php: https://github.com/nextcloud/server/pull/36836/files#diff-64a02ee1149d33d0747360694c2abf4ef1bdbfc379b4bb40f76c22b5b1fc06d9R203