nextcloud / server

lib/private/Files/SetupManager.php

Indentation +491 added lines, -491 removed lines

@@ -62,497 +62,497 @@
 use Psr\Log\LoggerInterface;
 
 class SetupManager {
-	private bool $rootSetup = false;
-	private IEventLogger $eventLogger;
-	private MountProviderCollection $mountProviderCollection;
-	private IMountManager $mountManager;
-	private IUserManager $userManager;
-	// List of users for which at least one mount is setup
-	private array $setupUsers = [];
-	// List of users for which all mounts are setup
-	private array $setupUsersComplete = [];
-	/** @var array<string, string[]> */
-	private array $setupUserMountProviders = [];
-	private IEventDispatcher $eventDispatcher;
-	private IUserMountCache $userMountCache;
-	private ILockdownManager $lockdownManager;
-	private IUserSession $userSession;
-	private ICache $cache;
-	private LoggerInterface $logger;
-	private IConfig $config;
-	private bool $listeningForProviders;
-	private array $fullSetupRequired = [];
-
-	public function __construct(
-		IEventLogger $eventLogger,
-		MountProviderCollection $mountProviderCollection,
-		IMountManager $mountManager,
-		IUserManager $userManager,
-		IEventDispatcher $eventDispatcher,
-		IUserMountCache $userMountCache,
-		ILockdownManager $lockdownManager,
-		IUserSession $userSession,
-		ICacheFactory $cacheFactory,
-		LoggerInterface $logger,
-		IConfig $config
-	) {
-		$this->eventLogger = $eventLogger;
-		$this->mountProviderCollection = $mountProviderCollection;
-		$this->mountManager = $mountManager;
-		$this->userManager = $userManager;
-		$this->eventDispatcher = $eventDispatcher;
-		$this->userMountCache = $userMountCache;
-		$this->lockdownManager = $lockdownManager;
-		$this->logger = $logger;
-		$this->userSession = $userSession;
-		$this->cache = $cacheFactory->createDistributed('setupmanager::');
-		$this->listeningForProviders = false;
-		$this->config = $config;
-
-		$this->setupListeners();
-	}
-
-	private function isSetupStarted(IUser $user): bool {
-		return in_array($user->getUID(), $this->setupUsers, true);
-	}
-
-	public function isSetupComplete(IUser $user): bool {
-		return in_array($user->getUID(), $this->setupUsersComplete, true);
-	}
-
-	private function setupBuiltinWrappers() {
-		Filesystem::addStorageWrapper('mount_options', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
-			if ($storage->instanceOfStorage(Common::class)) {
-				$storage->setMountOptions($mount->getOptions());
-			}
-			return $storage;
-		});
-
-		Filesystem::addStorageWrapper('enable_sharing', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
-			if (!$mount->getOption('enable_sharing', true)) {
-				return new PermissionsMask([
-					'storage' => $storage,
-					'mask' => Constants::PERMISSION_ALL - Constants::PERMISSION_SHARE,
-				]);
-			}
-			return $storage;
-		});
-
-		// install storage availability wrapper, before most other wrappers
-		Filesystem::addStorageWrapper('oc_availability', function ($mountPoint, IStorage $storage) {
-			if (!$storage->instanceOfStorage('\OCA\Files_Sharing\SharedStorage') && !$storage->isLocal()) {
-				return new Availability(['storage' => $storage]);
-			}
-			return $storage;
-		});
-
-		Filesystem::addStorageWrapper('oc_encoding', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
-			if ($mount->getOption('encoding_compatibility', false) && !$storage->instanceOfStorage('\OCA\Files_Sharing\SharedStorage') && !$storage->isLocal()) {
-				return new Encoding(['storage' => $storage]);
-			}
-			return $storage;
-		});
-
-		Filesystem::addStorageWrapper('oc_quota', function ($mountPoint, $storage) {
-			// set up quota for home storages, even for other users
-			// which can happen when using sharing
-
-			/**
-			 * @var Storage $storage
-			 */
-			if ($storage->instanceOfStorage(HomeObjectStoreStorage::class) || $storage->instanceOfStorage(Home::class)) {
-				if (is_object($storage->getUser())) {
-					$quota = OC_Util::getUserQuota($storage->getUser());
-					if ($quota !== \OCP\Files\FileInfo::SPACE_UNLIMITED) {
-						return new Quota(['storage' => $storage, 'quota' => $quota, 'root' => 'files']);
-					}
-				}
-			}
-
-			return $storage;
-		});
-
-		Filesystem::addStorageWrapper('readonly', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
-			/*
+    private bool $rootSetup = false;
+    private IEventLogger $eventLogger;
+    private MountProviderCollection $mountProviderCollection;
+    private IMountManager $mountManager;
+    private IUserManager $userManager;
+    // List of users for which at least one mount is setup
+    private array $setupUsers = [];
+    // List of users for which all mounts are setup
+    private array $setupUsersComplete = [];
+    /** @var array<string, string[]> */
+    private array $setupUserMountProviders = [];
+    private IEventDispatcher $eventDispatcher;
+    private IUserMountCache $userMountCache;
+    private ILockdownManager $lockdownManager;
+    private IUserSession $userSession;
+    private ICache $cache;
+    private LoggerInterface $logger;
+    private IConfig $config;
+    private bool $listeningForProviders;
+    private array $fullSetupRequired = [];
+
+    public function __construct(
+        IEventLogger $eventLogger,
+        MountProviderCollection $mountProviderCollection,
+        IMountManager $mountManager,
+        IUserManager $userManager,
+        IEventDispatcher $eventDispatcher,
+        IUserMountCache $userMountCache,
+        ILockdownManager $lockdownManager,
+        IUserSession $userSession,
+        ICacheFactory $cacheFactory,
+        LoggerInterface $logger,
+        IConfig $config
+    ) {
+        $this->eventLogger = $eventLogger;
+        $this->mountProviderCollection = $mountProviderCollection;
+        $this->mountManager = $mountManager;
+        $this->userManager = $userManager;
+        $this->eventDispatcher = $eventDispatcher;
+        $this->userMountCache = $userMountCache;
+        $this->lockdownManager = $lockdownManager;
+        $this->logger = $logger;
+        $this->userSession = $userSession;
+        $this->cache = $cacheFactory->createDistributed('setupmanager::');
+        $this->listeningForProviders = false;
+        $this->config = $config;
+
+        $this->setupListeners();
+    }
+
+    private function isSetupStarted(IUser $user): bool {
+        return in_array($user->getUID(), $this->setupUsers, true);
+    }
+
+    public function isSetupComplete(IUser $user): bool {
+        return in_array($user->getUID(), $this->setupUsersComplete, true);
+    }
+
+    private function setupBuiltinWrappers() {
+        Filesystem::addStorageWrapper('mount_options', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
+            if ($storage->instanceOfStorage(Common::class)) {
+                $storage->setMountOptions($mount->getOptions());
+            }
+            return $storage;
+        });
+
+        Filesystem::addStorageWrapper('enable_sharing', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
+            if (!$mount->getOption('enable_sharing', true)) {
+                return new PermissionsMask([
+                    'storage' => $storage,
+                    'mask' => Constants::PERMISSION_ALL - Constants::PERMISSION_SHARE,
+                ]);
+            }
+            return $storage;
+        });
+
+        // install storage availability wrapper, before most other wrappers
+        Filesystem::addStorageWrapper('oc_availability', function ($mountPoint, IStorage $storage) {
+            if (!$storage->instanceOfStorage('\OCA\Files_Sharing\SharedStorage') && !$storage->isLocal()) {
+                return new Availability(['storage' => $storage]);
+            }
+            return $storage;
+        });
+
+        Filesystem::addStorageWrapper('oc_encoding', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
+            if ($mount->getOption('encoding_compatibility', false) && !$storage->instanceOfStorage('\OCA\Files_Sharing\SharedStorage') && !$storage->isLocal()) {
+                return new Encoding(['storage' => $storage]);
+            }
+            return $storage;
+        });
+
+        Filesystem::addStorageWrapper('oc_quota', function ($mountPoint, $storage) {
+            // set up quota for home storages, even for other users
+            // which can happen when using sharing
+
+            /**
+             * @var Storage $storage
+             */
+            if ($storage->instanceOfStorage(HomeObjectStoreStorage::class) || $storage->instanceOfStorage(Home::class)) {
+                if (is_object($storage->getUser())) {
+                    $quota = OC_Util::getUserQuota($storage->getUser());
+                    if ($quota !== \OCP\Files\FileInfo::SPACE_UNLIMITED) {
+                        return new Quota(['storage' => $storage, 'quota' => $quota, 'root' => 'files']);
+                    }
+                }
+            }
+
+            return $storage;
+        });
+
+        Filesystem::addStorageWrapper('readonly', function ($mountPoint, IStorage $storage, IMountPoint $mount) {
+            /*
 			 * Do not allow any operations that modify the storage
 			 */
-			if ($mount->getOption('readonly', false)) {
-				return new PermissionsMask([
-					'storage' => $storage,
-					'mask' => Constants::PERMISSION_ALL & ~(
-							Constants::PERMISSION_UPDATE |
-							Constants::PERMISSION_CREATE |
-							Constants::PERMISSION_DELETE
-						),
-				]);
-			}
-			return $storage;
-		});
-	}
-
-	/**
-	 * Setup the full filesystem for the specified user
-	 */
-	public function setupForUser(IUser $user): void {
-		if ($this->isSetupComplete($user)) {
-			return;
-		}
-		$this->setupUsersComplete[] = $user->getUID();
-
-		if (!isset($this->setupUserMountProviders[$user->getUID()])) {
-			$this->setupUserMountProviders[$user->getUID()] = [];
-		}
-
-		$this->setupForUserWith($user, function () use ($user) {
-			$this->mountProviderCollection->addMountForUser($user, $this->mountManager, function (
-				IMountProvider $provider
-			) use ($user) {
-				return !in_array(get_class($provider), $this->setupUserMountProviders[$user->getUID()]);
-			});
-		});
-		$this->afterUserFullySetup($user);
-	}
-
-	/**
-	 * part of the user setup that is run only once per user
-	 */
-	private function oneTimeUserSetup(IUser $user) {
-		if (in_array($user->getUID(), $this->setupUsers, true)) {
-			return;
-		}
-		$this->setupUsers[] = $user->getUID();
-		$prevLogging = Filesystem::logWarningWhenAddingStorageWrapper(false);
-
-		OC_Hook::emit('OC_Filesystem', 'preSetup', ['user' => $user->getUID()]);
-
-		Filesystem::logWarningWhenAddingStorageWrapper($prevLogging);
-
-		$userDir = '/' . $user->getUID() . '/files';
-
-		Filesystem::initInternal($userDir);
-
-		if ($this->lockdownManager->canAccessFilesystem()) {
-			// home mounts are handled separate since we need to ensure this is mounted before we call the other mount providers
-			$homeMount = $this->mountProviderCollection->getHomeMountForUser($user);
-			$this->mountManager->addMount($homeMount);
-
-			if ($homeMount->getStorageRootId() === -1) {
-				$homeMount->getStorage()->mkdir('');
-				$homeMount->getStorage()->getScanner()->scan('');
-			}
-		} else {
-			$this->mountManager->addMount(new MountPoint(
-				new NullStorage([]),
-				'/' . $user->getUID()
-			));
-			$this->mountManager->addMount(new MountPoint(
-				new NullStorage([]),
-				'/' . $user->getUID() . '/files'
-			));
-			$this->setupUsersComplete[] = $user->getUID();
-		}
-
-		$this->listenForNewMountProviders();
-	}
-
-	/**
-	 * Final housekeeping after a user has been fully setup
-	 */
-	private function afterUserFullySetup(IUser $user): void {
-		$userRoot = '/' . $user->getUID() . '/';
-		$mounts = $this->mountManager->getAll();
-		$mounts = array_filter($mounts, function (IMountPoint $mount) use ($userRoot) {
-			return strpos($mount->getMountPoint(), $userRoot) === 0;
-		});
-		$this->userMountCache->registerMounts($user, $mounts);
-
-		$cacheDuration = $this->config->getSystemValueInt('fs_mount_cache_duration', 5 * 60);
-		if ($cacheDuration > 0) {
-			$this->cache->set($user->getUID(), true, $cacheDuration);
-			$this->fullSetupRequired[$user->getUID()] = false;
-		}
-	}
-
-	/**
-	 * @param IUser $user
-	 * @param IMountPoint $mounts
-	 * @return void
-	 * @throws \OCP\HintException
-	 * @throws \OC\ServerNotAvailableException
-	 */
-	private function setupForUserWith(IUser $user, callable $mountCallback): void {
-		$this->setupRoot();
-
-		if (!$this->isSetupStarted($user)) {
-			$this->oneTimeUserSetup($user);
-		}
-
-		$this->eventLogger->start('setup_fs', 'Setup filesystem');
-
-		if ($this->lockdownManager->canAccessFilesystem()) {
-			$mountCallback();
-		}
-		\OC_Hook::emit('OC_Filesystem', 'post_initMountPoints', ['user' => $user->getUID()]);
-
-		$userDir = '/' . $user->getUID() . '/files';
-		OC_Hook::emit('OC_Filesystem', 'setup', ['user' => $user->getUID(), 'user_dir' => $userDir]);
-
-		$this->eventLogger->end('setup_fs');
-	}
-
-	/**
-	 * Set up the root filesystem
-	 */
-	public function setupRoot(): void {
-		//setting up the filesystem twice can only lead to trouble
-		if ($this->rootSetup) {
-			return;
-		}
-		$this->rootSetup = true;
-
-		$this->eventLogger->start('setup_root_fs', 'Setup root filesystem');
-
-		// load all filesystem apps before, so no setup-hook gets lost
-		OC_App::loadApps(['filesystem']);
-		$prevLogging = Filesystem::logWarningWhenAddingStorageWrapper(false);
-
-		$this->setupBuiltinWrappers();
-
-		Filesystem::logWarningWhenAddingStorageWrapper($prevLogging);
-
-		$rootMounts = $this->mountProviderCollection->getRootMounts();
-		foreach ($rootMounts as $rootMountProvider) {
-			$this->mountManager->addMount($rootMountProvider);
-		}
-
-		$this->eventLogger->end('setup_root_fs');
-	}
-
-	/**
-	 * Get the user to setup for a path or `null` if the root needs to be setup
-	 *
-	 * @param string $path
-	 * @return IUser|null
-	 */
-	private function getUserForPath(string $path) {
-		if (substr_count($path, '/') < 2) {
-			if ($user = $this->userSession->getUser()) {
-				return $user;
-			} else {
-				return null;
-			}
-		} elseif (strpos($path, '/appdata_' . \OC_Util::getInstanceId()) === 0 || strpos($path, '/files_external/') === 0) {
-			return null;
-		} else {
-			[, $userId] = explode('/', $path);
-		}
-
-		return $this->userManager->get($userId);
-	}
-
-	/**
-	 * Set up the filesystem for the specified path
-	 */
-	public function setupForPath(string $path, bool $includeChildren = false): void {
-		$user = $this->getUserForPath($path);
-		if (!$user) {
-			$this->setupRoot();
-			return;
-		}
-
-		if ($this->isSetupComplete($user)) {
-			return;
-		}
-
-		if ($this->fullSetupRequired($user)) {
-			$this->setupForUser($user);
-			return;
-		}
-
-		// for the user's home folder, it's always the home mount
-		if (rtrim($path) === "/" . $user->getUID() . "/files") {
-			if ($includeChildren) {
-				$this->setupForUser($user);
-			} else {
-				$this->oneTimeUserSetup($user);
-			}
-			return;
-		}
-
-		if (!isset($this->setupUserMountProviders[$user->getUID()])) {
-			$this->setupUserMountProviders[$user->getUID()] = [];
-		}
-		$setupProviders = &$this->setupUserMountProviders[$user->getUID()];
-		$currentProviders = [];
-
-		try {
-			$cachedMount = $this->userMountCache->getMountForPath($user, $path);
-		} catch (NotFoundException $e) {
-			$this->setupForUser($user);
-			return;
-		}
-
-		$mounts = [];
-		if (!in_array($cachedMount->getMountProvider(), $setupProviders)) {
-			$setupProviders[] = $cachedMount->getMountProvider();
-			$currentProviders[] = $cachedMount->getMountProvider();
-			if ($cachedMount->getMountProvider()) {
-				$mounts = $this->mountProviderCollection->getUserMountsForProviderClasses($user, [$cachedMount->getMountProvider()]);
-			} else {
-				$this->logger->debug("mount at " . $cachedMount->getMountPoint() . " has no provider set, performing full setup");
-				$this->setupForUser($user);
-				return;
-			}
-		}
-
-		if ($includeChildren) {
-			$subCachedMounts = $this->userMountCache->getMountsInPath($user, $path);
-			foreach ($subCachedMounts as $cachedMount) {
-				if (!in_array($cachedMount->getMountProvider(), $setupProviders)) {
-					$setupProviders[] = $cachedMount->getMountProvider();
-					$currentProviders[] = $cachedMount->getMountProvider();
-					if ($cachedMount->getMountProvider()) {
-						$mounts = array_merge($mounts, $this->mountProviderCollection->getUserMountsForProviderClasses($user, [$cachedMount->getMountProvider()]));
-					} else {
-						$this->logger->debug("mount at " . $cachedMount->getMountPoint() . " has no provider set, performing full setup");
-						$this->setupForUser($user);
-						return;
-					}
-				}
-			}
-		}
-
-		if (count($mounts)) {
-			$this->userMountCache->registerMounts($user, $mounts, $currentProviders);
-			$this->setupForUserWith($user, function () use ($mounts) {
-				array_walk($mounts, [$this->mountManager, 'addMount']);
-			});
-		} elseif (!$this->isSetupStarted($user)) {
-			$this->oneTimeUserSetup($user);
-		}
-	}
-
-	private function fullSetupRequired(IUser $user): bool {
-		// we perform a "cached" setup only after having done the full setup recently
-		// this is also used to trigger a full setup after handling events that are likely
-		// to change the available mounts
-		if (!isset($this->fullSetupRequired[$user->getUID()])) {
-			$this->fullSetupRequired[$user->getUID()] = !$this->cache->get($user->getUID());
-		}
-		return $this->fullSetupRequired[$user->getUID()];
-	}
-
-	/**
-	 * @param string $path
-	 * @param string[] $providers
-	 */
-	public function setupForProvider(string $path, array $providers): void {
-		$user = $this->getUserForPath($path);
-		if (!$user) {
-			$this->setupRoot();
-			return;
-		}
-
-		if ($this->isSetupComplete($user)) {
-			return;
-		}
-
-		if ($this->fullSetupRequired($user)) {
-			$this->setupForUser($user);
-			return;
-		}
-
-		// home providers are always used
-		$providers = array_filter($providers, function (string $provider) {
-			return !is_subclass_of($provider, IHomeMountProvider::class);
-		});
-
-		if (in_array('', $providers)) {
-			$this->setupForUser($user);
-			return;
-		}
-		$setupProviders = $this->setupUserMountProviders[$user->getUID()] ?? [];
-
-		$providers = array_diff($providers, $setupProviders);
-		if (count($providers) === 0) {
-			if (!$this->isSetupStarted($user)) {
-				$this->oneTimeUserSetup($user);
-			}
-			return;
-		} else {
-			$this->setupUserMountProviders[$user->getUID()] = array_merge($setupProviders, $providers);
-			$mounts = $this->mountProviderCollection->getUserMountsForProviderClasses($user, $providers);
-		}
-
-		$this->userMountCache->registerMounts($user, $mounts, $providers);
-		$this->setupForUserWith($user, function () use ($mounts) {
-			array_walk($mounts, [$this->mountManager, 'addMount']);
-		});
-	}
-
-	public function tearDown() {
-		$this->setupUsers = [];
-		$this->setupUsersComplete = [];
-		$this->setupUserMountProviders = [];
-		$this->fullSetupRequired = [];
-		$this->rootSetup = false;
-		$this->mountManager->clear();
-		$this->eventDispatcher->dispatchTyped(new FilesystemTornDownEvent());
-	}
-
-	/**
-	 * Get mounts from mount providers that are registered after setup
-	 */
-	private function listenForNewMountProviders() {
-		if (!$this->listeningForProviders) {
-			$this->listeningForProviders = true;
-			$this->mountProviderCollection->listen('\OC\Files\Config', 'registerMountProvider', function (
-				IMountProvider $provider
-			) {
-				foreach ($this->setupUsers as $userId) {
-					$user = $this->userManager->get($userId);
-					if ($user) {
-						$mounts = $provider->getMountsForUser($user, Filesystem::getLoader());
-						array_walk($mounts, [$this->mountManager, 'addMount']);
-					}
-				}
-			});
-		}
-	}
-
-	private function setupListeners() {
-		// note that this event handling is intentionally pessimistic
-		// clearing the cache to often is better than not enough
-
-		$this->eventDispatcher->addListener(UserAddedEvent::class, function (UserAddedEvent $event) {
-			$this->cache->remove($event->getUser()->getUID());
-		});
-		$this->eventDispatcher->addListener(UserRemovedEvent::class, function (UserRemovedEvent $event) {
-			$this->cache->remove($event->getUser()->getUID());
-		});
-		$this->eventDispatcher->addListener(ShareCreatedEvent::class, function (ShareCreatedEvent $event) {
-			$this->cache->remove($event->getShare()->getSharedWith());
-		});
-		$this->eventDispatcher->addListener(InvalidateMountCacheEvent::class, function (InvalidateMountCacheEvent $event
-		) {
-			if ($user = $event->getUser()) {
-				$this->cache->remove($user->getUID());
-			} else {
-				$this->cache->clear();
-			}
-		});
-
-		$genericEvents = [
-			'\OCA\Circles::onCircleCreation',
-			'\OCA\Circles::onCircleDestruction',
-			'\OCA\Circles::onMemberNew',
-			'\OCA\Circles::onMemberLeaving',
-		];
-
-		foreach ($genericEvents as $genericEvent) {
-			$this->eventDispatcher->addListener($genericEvent, function ($event) {
-				$this->cache->clear();
-			});
-		}
-	}
+            if ($mount->getOption('readonly', false)) {
+                return new PermissionsMask([
+                    'storage' => $storage,
+                    'mask' => Constants::PERMISSION_ALL & ~(
+                            Constants::PERMISSION_UPDATE |
+                            Constants::PERMISSION_CREATE |
+                            Constants::PERMISSION_DELETE
+                        ),
+                ]);
+            }
+            return $storage;
+        });
+    }
+
+    /**
+     * Setup the full filesystem for the specified user
+     */
+    public function setupForUser(IUser $user): void {
+        if ($this->isSetupComplete($user)) {
+            return;
+        }
+        $this->setupUsersComplete[] = $user->getUID();
+
+        if (!isset($this->setupUserMountProviders[$user->getUID()])) {
+            $this->setupUserMountProviders[$user->getUID()] = [];
+        }
+
+        $this->setupForUserWith($user, function () use ($user) {
+            $this->mountProviderCollection->addMountForUser($user, $this->mountManager, function (
+                IMountProvider $provider
+            ) use ($user) {
+                return !in_array(get_class($provider), $this->setupUserMountProviders[$user->getUID()]);
+            });
+        });
+        $this->afterUserFullySetup($user);
+    }
+
+    /**
+     * part of the user setup that is run only once per user
+     */
+    private function oneTimeUserSetup(IUser $user) {
+        if (in_array($user->getUID(), $this->setupUsers, true)) {
+            return;
+        }
+        $this->setupUsers[] = $user->getUID();
+        $prevLogging = Filesystem::logWarningWhenAddingStorageWrapper(false);
+
+        OC_Hook::emit('OC_Filesystem', 'preSetup', ['user' => $user->getUID()]);
+
+        Filesystem::logWarningWhenAddingStorageWrapper($prevLogging);
+
+        $userDir = '/' . $user->getUID() . '/files';
+
+        Filesystem::initInternal($userDir);
+
+        if ($this->lockdownManager->canAccessFilesystem()) {
+            // home mounts are handled separate since we need to ensure this is mounted before we call the other mount providers
+            $homeMount = $this->mountProviderCollection->getHomeMountForUser($user);
+            $this->mountManager->addMount($homeMount);
+
+            if ($homeMount->getStorageRootId() === -1) {
+                $homeMount->getStorage()->mkdir('');
+                $homeMount->getStorage()->getScanner()->scan('');
+            }
+        } else {
+            $this->mountManager->addMount(new MountPoint(
+                new NullStorage([]),
+                '/' . $user->getUID()
+            ));
+            $this->mountManager->addMount(new MountPoint(
+                new NullStorage([]),
+                '/' . $user->getUID() . '/files'
+            ));
+            $this->setupUsersComplete[] = $user->getUID();
+        }
+
+        $this->listenForNewMountProviders();
+    }
+
+    /**
+     * Final housekeeping after a user has been fully setup
+     */
+    private function afterUserFullySetup(IUser $user): void {
+        $userRoot = '/' . $user->getUID() . '/';
+        $mounts = $this->mountManager->getAll();
+        $mounts = array_filter($mounts, function (IMountPoint $mount) use ($userRoot) {
+            return strpos($mount->getMountPoint(), $userRoot) === 0;
+        });
+        $this->userMountCache->registerMounts($user, $mounts);
+
+        $cacheDuration = $this->config->getSystemValueInt('fs_mount_cache_duration', 5 * 60);
+        if ($cacheDuration > 0) {
+            $this->cache->set($user->getUID(), true, $cacheDuration);
+            $this->fullSetupRequired[$user->getUID()] = false;
+        }
+    }
+
+    /**
+     * @param IUser $user
+     * @param IMountPoint $mounts
+     * @return void
+     * @throws \OCP\HintException
+     * @throws \OC\ServerNotAvailableException
+     */
+    private function setupForUserWith(IUser $user, callable $mountCallback): void {
+        $this->setupRoot();
+
+        if (!$this->isSetupStarted($user)) {
+            $this->oneTimeUserSetup($user);
+        }
+
+        $this->eventLogger->start('setup_fs', 'Setup filesystem');
+
+        if ($this->lockdownManager->canAccessFilesystem()) {
+            $mountCallback();
+        }
+        \OC_Hook::emit('OC_Filesystem', 'post_initMountPoints', ['user' => $user->getUID()]);
+
+        $userDir = '/' . $user->getUID() . '/files';
+        OC_Hook::emit('OC_Filesystem', 'setup', ['user' => $user->getUID(), 'user_dir' => $userDir]);
+
+        $this->eventLogger->end('setup_fs');
+    }
+
+    /**
+     * Set up the root filesystem
+     */
+    public function setupRoot(): void {
+        //setting up the filesystem twice can only lead to trouble
+        if ($this->rootSetup) {
+            return;
+        }
+        $this->rootSetup = true;
+
+        $this->eventLogger->start('setup_root_fs', 'Setup root filesystem');
+
+        // load all filesystem apps before, so no setup-hook gets lost
+        OC_App::loadApps(['filesystem']);
+        $prevLogging = Filesystem::logWarningWhenAddingStorageWrapper(false);
+
+        $this->setupBuiltinWrappers();
+
+        Filesystem::logWarningWhenAddingStorageWrapper($prevLogging);
+
+        $rootMounts = $this->mountProviderCollection->getRootMounts();
+        foreach ($rootMounts as $rootMountProvider) {
+            $this->mountManager->addMount($rootMountProvider);
+        }
+
+        $this->eventLogger->end('setup_root_fs');
+    }
+
+    /**
+     * Get the user to setup for a path or `null` if the root needs to be setup
+     *
+     * @param string $path
+     * @return IUser|null
+     */
+    private function getUserForPath(string $path) {
+        if (substr_count($path, '/') < 2) {
+            if ($user = $this->userSession->getUser()) {
+                return $user;
+            } else {
+                return null;
+            }
+        } elseif (strpos($path, '/appdata_' . \OC_Util::getInstanceId()) === 0 || strpos($path, '/files_external/') === 0) {
+            return null;
+        } else {
+            [, $userId] = explode('/', $path);
+        }
+
+        return $this->userManager->get($userId);
+    }
+
+    /**
+     * Set up the filesystem for the specified path
+     */
+    public function setupForPath(string $path, bool $includeChildren = false): void {
+        $user = $this->getUserForPath($path);
+        if (!$user) {
+            $this->setupRoot();
+            return;
+        }
+
+        if ($this->isSetupComplete($user)) {
+            return;
+        }
+
+        if ($this->fullSetupRequired($user)) {
+            $this->setupForUser($user);
+            return;
+        }
+
+        // for the user's home folder, it's always the home mount
+        if (rtrim($path) === "/" . $user->getUID() . "/files") {
+            if ($includeChildren) {
+                $this->setupForUser($user);
+            } else {
+                $this->oneTimeUserSetup($user);
+            }
+            return;
+        }
+
+        if (!isset($this->setupUserMountProviders[$user->getUID()])) {
+            $this->setupUserMountProviders[$user->getUID()] = [];
+        }
+        $setupProviders = &$this->setupUserMountProviders[$user->getUID()];
+        $currentProviders = [];
+
+        try {
+            $cachedMount = $this->userMountCache->getMountForPath($user, $path);
+        } catch (NotFoundException $e) {
+            $this->setupForUser($user);
+            return;
+        }
+
+        $mounts = [];
+        if (!in_array($cachedMount->getMountProvider(), $setupProviders)) {
+            $setupProviders[] = $cachedMount->getMountProvider();
+            $currentProviders[] = $cachedMount->getMountProvider();
+            if ($cachedMount->getMountProvider()) {
+                $mounts = $this->mountProviderCollection->getUserMountsForProviderClasses($user, [$cachedMount->getMountProvider()]);
+            } else {
+                $this->logger->debug("mount at " . $cachedMount->getMountPoint() . " has no provider set, performing full setup");
+                $this->setupForUser($user);
+                return;
+            }
+        }
+
+        if ($includeChildren) {
+            $subCachedMounts = $this->userMountCache->getMountsInPath($user, $path);
+            foreach ($subCachedMounts as $cachedMount) {
+                if (!in_array($cachedMount->getMountProvider(), $setupProviders)) {
+                    $setupProviders[] = $cachedMount->getMountProvider();
+                    $currentProviders[] = $cachedMount->getMountProvider();
+                    if ($cachedMount->getMountProvider()) {
+                        $mounts = array_merge($mounts, $this->mountProviderCollection->getUserMountsForProviderClasses($user, [$cachedMount->getMountProvider()]));
+                    } else {
+                        $this->logger->debug("mount at " . $cachedMount->getMountPoint() . " has no provider set, performing full setup");
+                        $this->setupForUser($user);
+                        return;
+                    }
+                }
+            }
+        }
+
+        if (count($mounts)) {
+            $this->userMountCache->registerMounts($user, $mounts, $currentProviders);
+            $this->setupForUserWith($user, function () use ($mounts) {
+                array_walk($mounts, [$this->mountManager, 'addMount']);
+            });
+        } elseif (!$this->isSetupStarted($user)) {
+            $this->oneTimeUserSetup($user);
+        }
+    }
+
+    private function fullSetupRequired(IUser $user): bool {
+        // we perform a "cached" setup only after having done the full setup recently
+        // this is also used to trigger a full setup after handling events that are likely
+        // to change the available mounts
+        if (!isset($this->fullSetupRequired[$user->getUID()])) {
+            $this->fullSetupRequired[$user->getUID()] = !$this->cache->get($user->getUID());
+        }
+        return $this->fullSetupRequired[$user->getUID()];
+    }
+
+    /**
+     * @param string $path
+     * @param string[] $providers
+     */
+    public function setupForProvider(string $path, array $providers): void {
+        $user = $this->getUserForPath($path);
+        if (!$user) {
+            $this->setupRoot();
+            return;
+        }
+
+        if ($this->isSetupComplete($user)) {
+            return;
+        }
+
+        if ($this->fullSetupRequired($user)) {
+            $this->setupForUser($user);
+            return;
+        }
+
+        // home providers are always used
+        $providers = array_filter($providers, function (string $provider) {
+            return !is_subclass_of($provider, IHomeMountProvider::class);
+        });
+
+        if (in_array('', $providers)) {
+            $this->setupForUser($user);
+            return;
+        }
+        $setupProviders = $this->setupUserMountProviders[$user->getUID()] ?? [];
+
+        $providers = array_diff($providers, $setupProviders);
+        if (count($providers) === 0) {
+            if (!$this->isSetupStarted($user)) {
+                $this->oneTimeUserSetup($user);
+            }
+            return;
+        } else {
+            $this->setupUserMountProviders[$user->getUID()] = array_merge($setupProviders, $providers);
+            $mounts = $this->mountProviderCollection->getUserMountsForProviderClasses($user, $providers);
+        }
+
+        $this->userMountCache->registerMounts($user, $mounts, $providers);
+        $this->setupForUserWith($user, function () use ($mounts) {
+            array_walk($mounts, [$this->mountManager, 'addMount']);
+        });
+    }
+
+    public function tearDown() {
+        $this->setupUsers = [];
+        $this->setupUsersComplete = [];
+        $this->setupUserMountProviders = [];
+        $this->fullSetupRequired = [];
+        $this->rootSetup = false;
+        $this->mountManager->clear();
+        $this->eventDispatcher->dispatchTyped(new FilesystemTornDownEvent());
+    }
+
+    /**
+     * Get mounts from mount providers that are registered after setup
+     */
+    private function listenForNewMountProviders() {
+        if (!$this->listeningForProviders) {
+            $this->listeningForProviders = true;
+            $this->mountProviderCollection->listen('\OC\Files\Config', 'registerMountProvider', function (
+                IMountProvider $provider
+            ) {
+                foreach ($this->setupUsers as $userId) {
+                    $user = $this->userManager->get($userId);
+                    if ($user) {
+                        $mounts = $provider->getMountsForUser($user, Filesystem::getLoader());
+                        array_walk($mounts, [$this->mountManager, 'addMount']);
+                    }
+                }
+            });
+        }
+    }
+
+    private function setupListeners() {
+        // note that this event handling is intentionally pessimistic
+        // clearing the cache to often is better than not enough
+
+        $this->eventDispatcher->addListener(UserAddedEvent::class, function (UserAddedEvent $event) {
+            $this->cache->remove($event->getUser()->getUID());
+        });
+        $this->eventDispatcher->addListener(UserRemovedEvent::class, function (UserRemovedEvent $event) {
+            $this->cache->remove($event->getUser()->getUID());
+        });
+        $this->eventDispatcher->addListener(ShareCreatedEvent::class, function (ShareCreatedEvent $event) {
+            $this->cache->remove($event->getShare()->getSharedWith());
+        });
+        $this->eventDispatcher->addListener(InvalidateMountCacheEvent::class, function (InvalidateMountCacheEvent $event
+        ) {
+            if ($user = $event->getUser()) {
+                $this->cache->remove($user->getUID());
+            } else {
+                $this->cache->clear();
+            }
+        });
+
+        $genericEvents = [
+            '\OCA\Circles::onCircleCreation',
+            '\OCA\Circles::onCircleDestruction',
+            '\OCA\Circles::onMemberNew',
+            '\OCA\Circles::onMemberLeaving',
+        ];
+
+        foreach ($genericEvents as $genericEvent) {
+            $this->eventDispatcher->addListener($genericEvent, function ($event) {
+                $this->cache->clear();
+            });
+        }
+    }
 }