DI of OCP\Files\Folder fails for guests

[nickvergessen]

E.g.

server/apps/comments/lib/Controller/Notifications.php

Line 75 in 0eebff1

Folder $folder,

TypeError
Argument 4 passed to OCA\Comments\Controller\Notifications::__construct() must implement interface OCP\Files\Folder, null given

The problem is, that the UserFolder is returned as null instead of something like e.g. NonExistingFolder

server/lib/private/AppFramework/DependencyInjection/DIContainer.php

Lines 111 to 113 in 0eebff1

	$this->registerService(IAppData::class, function (SimpleContainer $c) {
	return $this->getServer()->getAppDataDir($c->query('AppName'));
	});

So either all apps which use Folder injection need to allow = null manually or they will throw if one of the roots is invoked by a guest.

@icewind1991 do you think NonExistingFolder would make sense, or should we just advice all consumers of the app to explicitly allow null or inject IRootFolder instead and get the folder once they are sure it's a logged in user.

[nextcloud-bot]

GitMate.io thinks possibly related issues are #3636 (Update fails), #2737 (Updater fails to complete), #4683 (SharedStorageTest::testGetPermissions fails), #2043 (DI Container improvements), and #8299 (Decryption failed with s3).

[nickvergessen]

inject IRootFolder instead and get the folder once they are sure it's a logged in user.

After thinking a bit about it, I guess that this is actually the best idea, so fix is in #11185