enh(sharing): enable unsharing for sharees for DAV shares (addressbooks and calendars)

Signed-off-by: Anna Larch <anna@nextcloud.com>

8 files changed, 694 insertions, 50 deletions

diff --git a/apps/dav/tests/integration/DAV/Sharing/SharingMapperTest.php b/apps/dav/tests/integration/DAV/Sharing/SharingMapperTest.php
new file mode 100644
index 00000000000..249f11c3780
--- /dev/null
+++ b/apps/dav/tests/integration/DAV/Sharing/SharingMapperTest.php
@@ -0,0 +1,109 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * @copyright 2024 Anna Larch <anna.larch@gmx.net>
+ *
+ * @author Anna Larch <anna.larch@gmx.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+use OCA\DAV\DAV\Sharing\SharingMapper;
+use OCP\IDBConnection;
+use OCP\Server;
+use Test\TestCase;
+
+/**
+ * @group DB
+ */
+class SharingMapperTest extends TestCase {
+
+	private SharingMapper $mapper;
+	private IDBConnection $db;
+
+	protected function setUp(): void {
+		parent::setUp();
+
+		$this->db = Server::get(IDBConnection::class);
+		$this->mapper = new SharingMapper($this->db);
+		$qb = $this->db->getQueryBuilder();
+		$qb->delete('dav_shares')->executeStatement();
+	}
+
+	public function testShareAndGet(): void {
+		$resourceId = 42;
+		$resourceType = 'calendar';
+		$access = 3;
+		$principal = 'principals/users/bob';
+		$this->mapper->share($resourceId, $resourceType, $access, $principal);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertCount(1, $shares);
+	}
+
+	public function testShareDelete(): void {
+		$resourceId = 42;
+		$resourceType = 'calendar';
+		$access = 3;
+		$principal = 'principals/users/bob';
+		$this->mapper->share($resourceId, $resourceType, $access, $principal);
+		$this->mapper->deleteShare($resourceId, $resourceType, $principal);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertEmpty($shares);
+	}
+
+	public function testShareUnshare(): void {
+		$resourceId = 42;
+		$resourceType = 'calendar';
+		$access = 3;
+		$principal = 'principals/groups/alicegroup';
+		$userPrincipal = 'principals/users/alice';
+		$this->mapper->share($resourceId, $resourceType, $access, $principal);
+		$this->mapper->unshare($resourceId, $resourceType, $userPrincipal);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertCount(1, $shares);
+	}
+
+	public function testShareDeleteAll(): void {
+		$resourceId = 42;
+		$resourceType = 'calendar';
+		$access = 3;
+		$principal = 'principals/groups/alicegroup';
+		$userPrincipal = 'principals/users/alice';
+		$this->mapper->share($resourceId, $resourceType, $access, $principal);
+		$this->mapper->unshare($resourceId, $resourceType, $userPrincipal);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertCount(1, $shares);
+		$this->mapper->deleteAllShares($resourceId, $resourceType);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertEmpty($shares);
+	}
+
+	public function testShareDeleteAllForUser(): void {
+		$resourceId = 42;
+		$resourceType = 'calendar';
+		$access = 3;
+		$principal = 'principals/groups/alicegroup';
+		$this->mapper->share($resourceId, $resourceType, $access, $principal);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertCount(1, $shares);
+		$this->mapper->deleteAllSharesByUser($principal, $resourceType);
+		$shares = $this->mapper->getSharesForId($resourceId, $resourceType);
+		$this->assertEmpty($shares);
+	}
+
+}
diff --git a/apps/dav/tests/unit/CalDAV/AbstractCalDavBackend.php b/apps/dav/tests/unit/CalDAV/AbstractCalDavBackend.php
index 4dd61c6e307..dbed804ea41 100644
--- a/apps/dav/tests/unit/CalDAV/AbstractCalDavBackend.php
+++ b/apps/dav/tests/unit/CalDAV/AbstractCalDavBackend.php
@@ -30,10 +30,14 @@ namespace OCA\DAV\Tests\unit\CalDAV;
 use OC\KnownUser\KnownUserService;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\CalDAV\Proxy\ProxyMapper;
+use OCA\DAV\CalDAV\Sharing\Backend as SharingBackend;
+use OCA\DAV\CalDAV\Sharing\Service;
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\Sharing\SharingMapper;
 use OCP\Accounts\IAccountManager;
 use OCP\App\IAppManager;
 use OCP\EventDispatcher\IEventDispatcher;
+use OCP\ICacheFactory;
 use OCP\IConfig;
 use OCP\IGroupManager;
 use OCP\IUserManager;
@@ -56,26 +60,16 @@ use Test\TestCase;
  */
 abstract class AbstractCalDavBackend extends TestCase {
 
-	/** @var CalDavBackend */
-	protected $backend;
-
-	/** @var Principal | MockObject */
-	protected $principal;
-	/** @var IUserManager|MockObject */
-	protected $userManager;
-	/** @var IGroupManager|MockObject */
-	protected $groupManager;
-	/** @var IEventDispatcher|MockObject */
-	protected $dispatcher;
-
-
-	/** @var IConfig | MockObject */
-	private $config;
-	/** @var ISecureRandom */
-	private $random;
-	/** @var LoggerInterface*/
-	private $logger;
 
+	protected CalDavBackend $backend;
+	protected Principal|MockObject $principal;
+	protected IUserManager|MockObject $userManager;
+	protected IGroupManager|MockObject $groupManager;
+	protected IEventDispatcher|MockObject $dispatcher;
+	private LoggerInterface|MockObject $logger;
+	private IConfig|MockObject $config;
+	private ISecureRandom $random;
+	protected SharingBackend $sharingBackend;
 	public const UNIT_TEST_USER = 'principals/users/caldav-unit-test';
 	public const UNIT_TEST_USER1 = 'principals/users/caldav-unit-test1';
 	public const UNIT_TEST_GROUP = 'principals/groups/caldav-unit-test-group';
@@ -100,7 +94,7 @@ abstract class AbstractCalDavBackend extends TestCase {
 				$this->createMock(IConfig::class),
 				$this->createMock(IFactory::class)
 			])
-			->setMethods(['getPrincipalByPath', 'getGroupMembership'])
+			->setMethods(['getPrincipalByPath', 'getGroupMembership', 'findByUri'])
 			->getMock();
 		$this->principal->expects($this->any())->method('getPrincipalByPath')
 			->willReturn([
@@ -115,15 +109,23 @@ abstract class AbstractCalDavBackend extends TestCase {
 		$this->random = \OC::$server->getSecureRandom();
 		$this->logger = $this->createMock(LoggerInterface::class);
 		$this->config = $this->createMock(IConfig::class);
+		$this->sharingBackend = new SharingBackend(
+			$this->userManager,
+			$this->groupManager,
+			$this->principal,
+			$this->createMock(ICacheFactory::class),
+			new Service(new SharingMapper($db)),
+			$this->logger);
 		$this->backend = new CalDavBackend(
 			$db,
 			$this->principal,
 			$this->userManager,
-			$this->groupManager,
 			$this->random,
 			$this->logger,
 			$this->dispatcher,
-			$this->config
+			$this->config,
+			$this->sharingBackend,
+			false,
 		);
 
 		$this->cleanUpBackend();
diff --git a/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php b/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php
index b23091275ef..112786eb987 100644
--- a/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php
+++ b/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php
@@ -93,6 +93,9 @@ class CalDavBackendTest extends AbstractCalDavBackend {
 					'href' => 'principal:' . self::UNIT_TEST_GROUP,
 					'readOnly' => true
 				]
+			], [
+				self::UNIT_TEST_USER1,
+				self::UNIT_TEST_GROUP,
 			]],
 			[true, true, true, false, [
 				[
@@ -103,6 +106,9 @@ class CalDavBackendTest extends AbstractCalDavBackend {
 					'href' => 'principal:' . self::UNIT_TEST_GROUP2,
 					'readOnly' => false,
 				],
+			], [
+				self::UNIT_TEST_GROUP,
+				self::UNIT_TEST_GROUP2,
 			]],
 			[true, true, true, true, [
 				[
@@ -113,12 +119,17 @@ class CalDavBackendTest extends AbstractCalDavBackend {
 					'href' => 'principal:' . self::UNIT_TEST_GROUP2,
 					'readOnly' => true,
 				],
+			], [
+				self::UNIT_TEST_GROUP,
+				self::UNIT_TEST_GROUP2,
 			]],
 			[true, false, false, false, [
 				[
 					'href' => 'principal:' . self::UNIT_TEST_USER1,
 					'readOnly' => true
 				],
+			], [
+				self::UNIT_TEST_USER1,
 			]],
 
 		];
@@ -127,27 +138,26 @@ class CalDavBackendTest extends AbstractCalDavBackend {
 	/**
 	 * @dataProvider providesSharingData
 	 */
-	public function testCalendarSharing($userCanRead, $userCanWrite, $groupCanRead, $groupCanWrite, $add): void {
-		/** @var IL10N|\PHPUnit\Framework\MockObject\MockObject $l10n */
+	public function testCalendarSharing($userCanRead, $userCanWrite, $groupCanRead, $groupCanWrite, $add, $principals): void {
+		$logger = $this->createMock(\Psr\Log\LoggerInterface::class);
+		$config = $this->createMock(IConfig::class);
+		/** @var IL10N|MockObject $l10n */
 		$l10n = $this->createMock(IL10N::class);
-		$l10n
-			->expects($this->any())
+		$l10n->expects($this->any())
 			->method('t')
 			->willReturnCallback(function ($text, $parameters = []) {
 				return vsprintf($text, $parameters);
 			});
 
-		$logger = $this->createMock(\Psr\Log\LoggerInterface::class);
-
-		$config = $this->createMock(IConfig::class);
-
 		$this->userManager->expects($this->any())
 			->method('userExists')
 			->willReturn(true);
-
 		$this->groupManager->expects($this->any())
 			->method('groupExists')
 			->willReturn(true);
+		$this->principal->expects(self::atLeastOnce())
+			->method('findByUri')
+			->willReturnOnConsecutiveCalls(...$principals);
 
 		$calendarId = $this->createTestCalendar();
 		$calendars = $this->backend->getCalendarsForUser(self::UNIT_TEST_USER);
@@ -1250,6 +1260,9 @@ EOD;
 		$this->groupManager->expects($this->any())
 			->method('groupExists')
 			->willReturn(true);
+		$this->principal->expects(self::atLeastOnce())
+			->method('findByUri')
+			->willReturn(self::UNIT_TEST_USER);
 
 		$me = self::UNIT_TEST_USER;
 		$sharer = self::UNIT_TEST_USER1;
diff --git a/apps/dav/tests/unit/CalDAV/CalendarTest.php b/apps/dav/tests/unit/CalDAV/CalendarTest.php
index d61e4b58478..68e6e5ef251 100644
--- a/apps/dav/tests/unit/CalDAV/CalendarTest.php
+++ b/apps/dav/tests/unit/CalDAV/CalendarTest.php
@@ -83,11 +83,9 @@ class CalendarTest extends TestCase {
 
 
 	public function testDeleteFromGroup(): void {
-		$this->expectException(\Sabre\DAV\Exception\Forbidden::class);
-
 		/** @var MockObject | CalDavBackend $backend */
 		$backend = $this->getMockBuilder(CalDavBackend::class)->disableOriginalConstructor()->getMock();
-		$backend->expects($this->never())->method('updateShares');
+		$backend->expects($this->once())->method('updateShares');
 		$backend->expects($this->any())->method('getShares')->willReturn([
 			['href' => 'principal:group2']
 		]);
diff --git a/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php b/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php
index 6634a602e74..3460c548de4 100644
--- a/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php
+++ b/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php
@@ -84,6 +84,7 @@ class PublicCalendarRootTest extends TestCase {
 		$this->logger = $this->createMock(LoggerInterface::class);
 		$dispatcher = $this->createMock(IEventDispatcher::class);
 		$config = $this->createMock(IConfig::class);
+		$sharingBackend = $this->createMock(\OCA\DAV\CalDAV\Sharing\Backend::class);
 
 		$this->principal->expects($this->any())->method('getGroupMembership')
 			->withAnyParameters()
@@ -97,11 +98,12 @@ class PublicCalendarRootTest extends TestCase {
 			$db,
 			$this->principal,
 			$this->userManager,
-			$this->groupManager,
 			$this->random,
 			$this->logger,
 			$dispatcher,
-			$config
+			$config,
+			$sharingBackend,
+			false,
 		);
 		$this->l10n = $this->getMockBuilder(IL10N::class)
 			->disableOriginalConstructor()->getMock();
diff --git a/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php b/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
index 425e7c44ba7..ea80187f554 100644
--- a/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
+++ b/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
@@ -37,11 +37,15 @@ use OC\KnownUser\KnownUserService;
 use OCA\DAV\CalDAV\Proxy\ProxyMapper;
 use OCA\DAV\CardDAV\AddressBook;
 use OCA\DAV\CardDAV\CardDavBackend;
+use OCA\DAV\CardDAV\Sharing\Backend;
+use OCA\DAV\CardDAV\Sharing\Service;
 use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\Sharing\SharingMapper;
 use OCP\Accounts\IAccountManager;
 use OCP\App\IAppManager;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\EventDispatcher\IEventDispatcher;
+use OCP\ICacheFactory;
 use OCP\IConfig;
 use OCP\IDBConnection;
 use OCP\IGroupManager;
@@ -50,6 +54,7 @@ use OCP\IUserManager;
 use OCP\IUserSession;
 use OCP\L10N\IFactory;
 use OCP\Share\IManager as ShareManager;
+use Psr\Log\LoggerInterface;
 use Sabre\DAV\Exception\BadRequest;
 use Sabre\DAV\PropPatch;
 use Sabre\VObject\Component\VCard;
@@ -78,7 +83,7 @@ class CardDavBackendTest extends TestCase {
 
 	/** @var IEventDispatcher|MockObject */
 	private $dispatcher;
-
+	private Backend $sharingBackend;
 	/** @var  IDBConnection */
 	private $db;
 
@@ -141,7 +146,7 @@ class CardDavBackendTest extends TestCase {
 				$this->createMock(IConfig::class),
 				$this->createMock(IFactory::class)
 			])
-			->setMethods(['getPrincipalByPath', 'getGroupMembership'])
+			->setMethods(['getPrincipalByPath', 'getGroupMembership', 'findByUri'])
 			->getMock();
 		$this->principal->method('getPrincipalByPath')
 			->willReturn([
@@ -154,8 +159,20 @@ class CardDavBackendTest extends TestCase {
 		$this->dispatcher = $this->createMock(IEventDispatcher::class);
 
 		$this->db = \OC::$server->getDatabaseConnection();
-
-		$this->backend = new CardDavBackend($this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher);
+		$this->sharingBackend = new Backend($this->userManager,
+			$this->groupManager,
+			$this->principal,
+			$this->createMock(ICacheFactory::class),
+			new Service(new SharingMapper($this->db)),
+			$this->createMock(LoggerInterface::class)
+		);
+
+		$this->backend = new CardDavBackend($this->db,
+			$this->principal,
+			$this->userManager,
+			$this->dispatcher,
+			$this->sharingBackend,
+		);
 		// start every test with a empty cards_properties and cards table
 		$query = $this->db->getQueryBuilder();
 		$query->delete('cards_properties')->execute();
@@ -213,10 +230,12 @@ class CardDavBackendTest extends TestCase {
 		$this->userManager->expects($this->any())
 			->method('userExists')
 			->willReturn(true);
-
 		$this->groupManager->expects($this->any())
 			->method('groupExists')
 			->willReturn(true);
+		$this->principal->expects(self::atLeastOnce())
+			->method('findByUri')
+			->willReturnOnConsecutiveCalls(self::UNIT_TEST_USER1, self::UNIT_TEST_GROUP);
 
 		$this->backend->createAddressBook(self::UNIT_TEST_USER, 'Example', []);
 		$books = $this->backend->getAddressBooksForUser(self::UNIT_TEST_USER);
@@ -243,7 +262,7 @@ class CardDavBackendTest extends TestCase {
 	public function testCardOperations(): void {
 		/** @var CardDavBackend | \PHPUnit\Framework\MockObject\MockObject $backend */
 		$backend = $this->getMockBuilder(CardDavBackend::class)
-				->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+				->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 				->onlyMethods(['updateProperties', 'purgeProperties'])->getMock();
 
 		// create a new address book
@@ -298,7 +317,7 @@ class CardDavBackendTest extends TestCase {
 
 	public function testMultiCard(): void {
 		$this->backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->setMethods(['updateProperties'])->getMock();
 
 		// create a new address book
@@ -351,7 +370,7 @@ class CardDavBackendTest extends TestCase {
 
 	public function testMultipleUIDOnDifferentAddressbooks(): void {
 		$this->backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->onlyMethods(['updateProperties'])->getMock();
 
 		// create 2 new address books
@@ -373,7 +392,7 @@ class CardDavBackendTest extends TestCase {
 
 	public function testMultipleUIDDenied(): void {
 		$this->backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->setMethods(['updateProperties'])->getMock();
 
 		// create a new address book
@@ -394,7 +413,7 @@ class CardDavBackendTest extends TestCase {
 
 	public function testNoValidUID(): void {
 		$this->backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->setMethods(['updateProperties'])->getMock();
 
 		// create a new address book
@@ -411,7 +430,7 @@ class CardDavBackendTest extends TestCase {
 
 	public function testDeleteWithoutCard(): void {
 		$this->backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->onlyMethods([
 				'getCardId',
 				'addChange',
@@ -451,7 +470,7 @@ class CardDavBackendTest extends TestCase {
 
 	public function testSyncSupport(): void {
 		$this->backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->setMethods(['updateProperties'])->getMock();
 
 		// create a new address book
@@ -477,10 +496,12 @@ class CardDavBackendTest extends TestCase {
 		$this->userManager->expects($this->any())
 			->method('userExists')
 			->willReturn(true);
-
 		$this->groupManager->expects($this->any())
 			->method('groupExists')
 			->willReturn(true);
+		$this->principal->expects(self::any())
+			->method('findByUri')
+			->willReturn(self::UNIT_TEST_USER1);
 
 		$this->backend->createAddressBook(self::UNIT_TEST_USER, 'Example', []);
 		$books = $this->backend->getAddressBooksForUser(self::UNIT_TEST_USER);
@@ -517,7 +538,7 @@ class CardDavBackendTest extends TestCase {
 		$cardId = 2;
 
 		$backend = $this->getMockBuilder(CardDavBackend::class)
-			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->groupManager, $this->dispatcher])
+			->setConstructorArgs([$this->db, $this->principal, $this->userManager, $this->dispatcher, $this->sharingBackend])
 			->onlyMethods(['getCardId'])->getMock();
 
 		$backend->expects($this->any())->method('getCardId')->willReturn($cardId);
diff --git a/apps/dav/tests/unit/DAV/Sharing/BackendTest.php b/apps/dav/tests/unit/DAV/Sharing/BackendTest.php
new file mode 100644
index 00000000000..eaa8f3805a1
--- /dev/null
+++ b/apps/dav/tests/unit/DAV/Sharing/BackendTest.php
@@ -0,0 +1,427 @@
+<?php
+
+declare(strict_types=1);
+/*
+ * @copyright 2024 Anna Larch <anna.larch@gmx.net>
+ *
+ * @author Anna Larch <anna.larch@gmx.net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+namespace OCA\DAV\Tests\unit\DAV\Sharing;
+
+use OCA\DAV\CalDAV\Sharing\Backend as CalendarSharingBackend;
+use OCA\DAV\CalDAV\Sharing\Service;
+use OCA\DAV\CardDAV\Sharing\Backend as ContactsSharingBackend;
+use OCA\DAV\Connector\Sabre\Principal;
+use OCA\DAV\DAV\Sharing\Backend;
+use OCA\DAV\DAV\Sharing\IShareable;
+use OCP\ICache;
+use OCP\ICacheFactory;
+use OCP\IDBConnection;
+use OCP\IGroupManager;
+use OCP\IUserManager;
+use PHPUnit\Framework\MockObject\MockObject;
+use Psr\Log\LoggerInterface;
+use Test\TestCase;
+
+class BackendTest extends TestCase {
+
+	private IDBConnection|MockObject $db;
+	private IUserManager|MockObject $userManager;
+	private IGroupManager|MockObject $groupManager;
+	private MockObject|Principal $principalBackend;
+	private MockObject|ICache $shareCache;
+	private LoggerInterface|MockObject $logger;
+	private MockObject|ICacheFactory $cacheFactory;
+	private Service|MockObject $calendarService;
+	private CalendarSharingBackend $backend;
+
+	protected function setUp(): void {
+		parent::setUp();
+		$this->db = $this->createMock(IDBConnection::class);
+		$this->userManager = $this->createMock(IUserManager::class);
+		$this->groupManager = $this->createMock(IGroupManager::class);
+		$this->principalBackend = $this->createMock(Principal::class);
+		$this->cacheFactory = $this->createMock(ICacheFactory::class);
+		$this->shareCache = $this->createMock(ICache::class);
+		$this->logger = $this->createMock(LoggerInterface::class);
+		$this->calendarService = $this->createMock(Service::class);
+		$this->cacheFactory->expects(self::any())
+			->method('createInMemory')
+			->willReturn($this->shareCache);
+
+		$this->backend = new CalendarSharingBackend(
+			$this->userManager,
+			$this->groupManager,
+			$this->principalBackend,
+			$this->cacheFactory,
+			$this->calendarService,
+			$this->logger,
+		);
+	}
+
+	public function testUpdateShareCalendarBob(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$add = [
+			[
+				'href' => 'principal:principals/users/bob',
+				'readOnly' => true,
+			]
+		];
+		$principal = 'principals/users/bob';
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn($principal);
+		$this->userManager->expects(self::once())
+			->method('userExists')
+			->willReturn(true);
+		$this->groupManager->expects(self::never())
+			->method('groupExists');
+		$this->calendarService->expects(self::once())
+			->method('shareWith')
+			->with($shareable->getResourceId(), $principal, Backend::ACCESS_READ);
+
+		$this->backend->updateShares($shareable, $add, []);
+	}
+
+	public function testUpdateShareCalendarGroup(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$add = [
+			[
+				'href' => 'principal:principals/groups/bob',
+				'readOnly' => true,
+			]
+		];
+		$principal = 'principals/groups/bob';
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn($principal);
+		$this->userManager->expects(self::never())
+			->method('userExists');
+		$this->groupManager->expects(self::once())
+			->method('groupExists')
+			->willReturn(true);
+		$this->calendarService->expects(self::once())
+			->method('shareWith')
+			->with($shareable->getResourceId(), $principal, Backend::ACCESS_READ);
+
+		$this->backend->updateShares($shareable, $add, []);
+	}
+
+	public function testUpdateShareContactsBob(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$add = [
+			[
+				'href' => 'principal:principals/users/bob',
+				'readOnly' => true,
+			]
+		];
+		$principal = 'principals/users/bob';
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn($principal);
+		$this->userManager->expects(self::once())
+			->method('userExists')
+			->willReturn(true);
+		$this->groupManager->expects(self::never())
+			->method('groupExists');
+		$this->calendarService->expects(self::once())
+			->method('shareWith')
+			->with($shareable->getResourceId(), $principal, Backend::ACCESS_READ);
+
+		$this->backend->updateShares($shareable, $add, []);
+	}
+
+	public function testUpdateShareContactsGroup(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$add = [
+			[
+				'href' => 'principal:principals/groups/bob',
+				'readOnly' => true,
+			]
+		];
+		$principal = 'principals/groups/bob';
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn($principal);
+		$this->userManager->expects(self::never())
+			->method('userExists');
+		$this->groupManager->expects(self::once())
+			->method('groupExists')
+			->willReturn(true);
+		$this->calendarService->expects(self::once())
+			->method('shareWith')
+			->with($shareable->getResourceId(), $principal, Backend::ACCESS_READ);
+
+		$this->backend->updateShares($shareable, $add, []);
+	}
+
+	public function testUpdateShareCircle(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$add = [
+			[
+				'href' => 'principal:principals/circles/bob',
+				'readOnly' => true,
+			]
+		];
+		$principal = 'principals/groups/bob';
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn($principal);
+		$this->userManager->expects(self::never())
+			->method('userExists');
+		$this->groupManager->expects(self::once())
+			->method('groupExists')
+			->willReturn(true);
+		$this->calendarService->expects(self::once())
+			->method('shareWith')
+			->with($shareable->getResourceId(), $principal, Backend::ACCESS_READ);
+
+		$this->backend->updateShares($shareable, $add, []);
+	}
+
+	public function testUnshareBob(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$remove = [
+			[
+				'href' => 'principal:principals/users/bob',
+				'readOnly' => true,
+			]
+		];
+		$principal = 'principals/users/bob';
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn($principal);
+		$this->calendarService->expects(self::once())
+			->method('deleteShare')
+			->with($shareable->getResourceId(), $principal);
+		$this->calendarService->expects(self::once())
+			->method('hasGroupShare')
+			->willReturn(false);
+		$this->calendarService->expects(self::never())
+			->method('unshare');
+
+		$this->backend->updateShares($shareable, [], $remove);
+	}
+
+	public function testUnshareWithBobGroup(): void {
+		$shareable = $this->createConfiguredMock(IShareable::class, [
+			'getOwner' => 'principals/users/alice',
+			'getResourceId' => 42,
+		]);
+		$remove = [
+			[
+				'href' => 'principal:principals/users/bob',
+				'readOnly' => true,
+			]
+		];
+		$oldShares = [
+			[
+				'href' => 'principal:principals/groups/bob',
+				'commonName' => 'bob',
+				'status' => 1,
+				'readOnly' => true,
+				'{http://owncloud.org/ns}principal' => 'principals/groups/bob',
+				'{http://owncloud.org/ns}group-share' => true,
+			]
+		];
+
+
+		$this->shareCache->expects(self::once())
+			->method('clear');
+		$this->principalBackend->expects(self::once())
+			->method('findByUri')
+			->willReturn('principals/users/bob');
+		$this->calendarService->expects(self::once())
+			->method('deleteShare')
+			->with($shareable->getResourceId(), 'principals/users/bob');
+		$this->calendarService->expects(self::once())
+			->method('hasGroupShare')
+			->with($oldShares)
+			->willReturn(true);
+		$this->calendarService->expects(self::once())
+			->method('unshare')
+			->with($shareable->getResourceId(), 'principals/users/bob');
+
+		$this->backend->updateShares($shareable, [], $remove, $oldShares);
+	}
+
+	public function testGetShares(): void {
+		$resourceId = 42;
+		$principal = 'principals/groups/bob';
+		$rows = [
+			[
+				'principaluri' => $principal,
+				'access' => Backend::ACCESS_READ,
+			]
+		];
+		$expected = [
+			[
+				'href' => 'principal:principals/groups/bob',
+				'commonName' => 'bob',
+				'status' => 1,
+				'readOnly' => true,
+				'{http://owncloud.org/ns}principal' => $principal,
+				'{http://owncloud.org/ns}group-share' => true,
+			]
+		];
+
+
+		$this->shareCache->expects(self::once())
+			->method('get')
+			->with((string)$resourceId)
+			->willReturn(null);
+		$this->calendarService->expects(self::once())
+			->method('getShares')
+			->with($resourceId)
+			->willReturn($rows);
+		$this->principalBackend->expects(self::once())
+			->method('getPrincipalByPath')
+			->with($principal)
+			->willReturn(['uri' => $principal, '{DAV:}displayname' => 'bob']);
+		$this->shareCache->expects(self::once())
+			->method('set')
+			->with((string)$resourceId, $expected);
+
+		$result = $this->backend->getShares($resourceId);
+		$this->assertEquals($expected, $result);
+	}
+
+	public function testGetSharesAddressbooks(): void {
+		$service = $this->createMock(\OCA\DAV\CardDAV\Sharing\Service::class);
+		$backend = new ContactsSharingBackend(
+			$this->userManager,
+			$this->groupManager,
+			$this->principalBackend,
+			$this->cacheFactory,
+			$service,
+			$this->logger);
+		$resourceId = 42;
+		$principal = 'principals/groups/bob';
+		$rows = [
+			[
+				'principaluri' => $principal,
+				'access' => Backend::ACCESS_READ,
+			]
+		];
+		$expected = [
+			[
+				'href' => 'principal:principals/groups/bob',
+				'commonName' => 'bob',
+				'status' => 1,
+				'readOnly' => true,
+				'{http://owncloud.org/ns}principal' => $principal,
+				'{http://owncloud.org/ns}group-share' => true,
+			]
+		];
+
+		$this->shareCache->expects(self::once())
+			->method('get')
+			->with((string)$resourceId)
+			->willReturn(null);
+		$service->expects(self::once())
+			->method('getShares')
+			->with($resourceId)
+			->willReturn($rows);
+		$this->principalBackend->expects(self::once())
+			->method('getPrincipalByPath')
+			->with($principal)
+			->willReturn(['uri' => $principal, '{DAV:}displayname' => 'bob']);
+		$this->shareCache->expects(self::once())
+			->method('set')
+			->with((string)$resourceId, $expected);
+
+		$result = $backend->getShares($resourceId);
+		$this->assertEquals($expected, $result);
+	}
+
+	public function testPreloadShares(): void {
+		$resourceIds = [42, 99];
+		$rows = [
+			[
+				'resourceid' => 42,
+				'principaluri' => 'principals/groups/bob',
+				'access' => Backend::ACCESS_READ,
+			],
+			[
+				'resourceid' => 99,
+				'principaluri' => 'principals/users/carlos',
+				'access' => Backend::ACCESS_READ_WRITE,
+			]
+		];
+		$principalResults = [
+			['uri' => 'principals/groups/bob', '{DAV:}displayname' => 'bob'],
+			['uri' => 'principals/users/carlos', '{DAV:}displayname' => 'carlos'],
+		];
+
+		$this->shareCache->expects(self::exactly(2))
+			->method('get')
+			->willReturn(null);
+		$this->calendarService->expects(self::once())
+			->method('getSharesForIds')
+			->with($resourceIds)
+			->willReturn($rows);
+		$this->principalBackend->expects(self::exactly(2))
+			->method('getPrincipalByPath')
+			->willReturnCallback(function (string $principal) use ($principalResults) {
+				switch ($principal) {
+					case 'principals/groups/bob':
+						return $principalResults[0];
+					default:
+						return $principalResults[1];
+				}
+			});
+		$this->shareCache->expects(self::exactly(2))
+			->method('set');
+
+		$this->backend->preloadShares($resourceIds);
+	}
+}
diff --git a/apps/dav/tests/unit/DAV/Sharing/SharingServiceTest.php b/apps/dav/tests/unit/DAV/Sharing/SharingServiceTest.php
new file mode 100644
index 00000000000..97cd3176d3b
--- /dev/null
+++ b/apps/dav/tests/unit/DAV/Sharing/SharingServiceTest.php
@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+/*
+ * @copyright 2024 Anna Larch <anna.larch@gmx.net>
+ *
+ * @author Anna Larch <anna.larch@gmx.net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+namespace OCA\DAV\Tests\unit\DAV\Sharing;
+
+use OCA\DAV\CalDAV\Sharing\Service;
+use OCA\DAV\DAV\Sharing\SharingMapper;
+use OCA\DAV\DAV\Sharing\SharingService;
+use Test\TestCase;
+
+class SharingServiceTest extends TestCase {
+
+	private SharingService $service;
+
+	protected function setUp(): void {
+		parent::setUp();
+		$this->service = new Service($this->createMock(SharingMapper::class));
+	}
+
+	public function testHasGroupShare(): void {
+		$oldShares = [
+			[
+				'href' => 'principal:principals/groups/bob',
+				'commonName' => 'bob',
+				'status' => 1,
+				'readOnly' => true,
+				'{http://owncloud.org/ns}principal' => 'principals/groups/bob',
+				'{http://owncloud.org/ns}group-share' => true,
+			],
+			[
+				'href' => 'principal:principals/users/bob',
+				'commonName' => 'bob',
+				'status' => 1,
+				'readOnly' => true,
+				'{http://owncloud.org/ns}principal' => 'principals/users/bob',
+				'{http://owncloud.org/ns}group-share' => false,
+			]
+		];
+
+		$this->assertTrue($this->service->hasGroupShare($oldShares));
+
+		$oldShares = [
+			[
+				'href' => 'principal:principals/users/bob',
+				'commonName' => 'bob',
+				'status' => 1,
+				'readOnly' => true,
+				'{http://owncloud.org/ns}principal' => 'principals/users/bob',
+				'{http://owncloud.org/ns}group-share' => false,
+			]
+		];
+		$this->assertFalse($this->service->hasGroupShare($oldShares));
+	}
+}