Changes for implementing the new sync mech from core

lib/AppInfo/Application.php

@@ -25,6 +25,7 @@
 use OCA\User_LDAP\Helper;
 use OCA\User_LDAP\LDAP;
 use OCA\User_LDAP\User_Proxy;
+use OCA\User_LDAP\UserSyncLDAPBackend;
 
 class Application extends \OCP\AppFramework\App {
 	/**
@@ -82,6 +83,18 @@ public function registerBackends() {
 			// register user backend
 			\OC_User::useBackend($userBackend);
 			$server->getGroupManager()->addBackend($groupBackend);
+
+			// conditionally add the userSync backend if it's available
+			// in order to keep backwards compatibility
+			if (\method_exists($server, 'getSyncManager')) {
+				$syncManager = $server->getSyncManager();
+				$userSyncer = $syncManager->getUserSyncer();
+				if ($userSyncer !== null) {
+					$userSyncer->registerBackend(
+						new UserSyncLDAPBackend($userBackend)
+					);
+				}
+			}
 		}
 	}
 

lib/Connection.php

@@ -600,7 +600,7 @@ private function establishConnection() {
 						'Bind failed: ' . $this->getLDAP()->errno($this->ldapConnectionRes) . ': ' . $this->getLDAP()->error($this->ldapConnectionRes),
 						Util::DEBUG
 					);
-					throw new BindFailedException();
+					throw new BindFailedException("Cannot bind to the LDAP server");
 				}
 			} catch (ServerNotAvailableException|BindFailedException $e) {
 				if (\trim($this->configuration->ldapBackupHost) === "") {
@@ -693,6 +693,11 @@ public function bind() {
 		}
 
 		// binding is done via getConnectionResource()
+		// need to reset the connection to throw exception, otherwise
+		// the exception is thrown only for the first bind but not for
+		// the rest, because the resource is valid even though the
+		// bind failed.
+		$this->resetConnectionResource();
 		$cr = $this->getConnectionResource();
 
 		if (!$this->getLDAP()->isResource($cr)) {

lib/User/Manager.php

@@ -492,6 +492,35 @@ public function getLDAPUserByLoginName($loginName) {
 	 * @return string[] an array of all uids
 	 */
 	public function getUsers($search = '', $limit = 10, $offset = 0) {
+		$ldap_users = $this->getLdapUsers($search, $limit, $offset);
+		$owncloudNames = [];
+		foreach ($ldap_users as $ldapEntry) {
+			try {
+				$userEntry = $this->getFromEntry($ldapEntry);
+				$this->logger->debug(
+					"Caching ldap entry for <{$ldapEntry['dn'][0]}>:".\json_encode($ldapEntry),
+					['app' => self::class]
+				);
+				$owncloudNames[] = $userEntry->getOwnCloudUID();
+			} catch (\OutOfBoundsException $e) {
+				// tell the admin why we skip the user
+				$this->logger->logException($e, ['app' => self::class]);
+			}
+		}
+
+		return $owncloudNames;
+	}
+
+	/**
+	 * Get a list of all users, as raw ldap info
+	 *
+	 * @param string $search
+	 * @param integer $limit
+	 * @param integer $offset
+	 * @return array an array containing the information about the users
+	 * as returned by the ldap library.
+	 */
+	public function getLdapUsers($search = '', $limit = 10, $offset = 0) {
 		$search = $this->access->escapeFilterPart($search, true);
 
 		// if we'd pass -1 to LDAP search, we'd end up in a Protocol
@@ -506,7 +535,7 @@ public function getUsers($search = '', $limit = 10, $offset = 0) {
 		]);
 
 		$this->logger->debug(
-			'getUsers: Options: search '.$search
+			'getLdapUsers: Options: search '.$search
 			.' limit '.$limit
 			.' offset ' .$offset
 			.' Filter: '.$filter,
@@ -520,24 +549,9 @@ public function getUsers($search = '', $limit = 10, $offset = 0) {
 			$limit,
 			$offset
 		);
-		$ownCloudUserNames = [];
-		foreach ($ldap_users as $ldapEntry) {
-			try {
-				$userEntry = $this->getFromEntry($ldapEntry);
-				$this->logger->debug(
-					"Caching ldap entry for <{$ldapEntry['dn'][0]}>:".\json_encode($ldapEntry),
-					['app' => self::class]
-				);
-				$ownCloudUserNames[] = $userEntry->getOwnCloudUID();
-			} catch (\OutOfBoundsException $e) {
-				// tell the admin why we skip the user
-				$this->logger->logException($e, ['app' => self::class]);
-			}
-		}
-
-		$this->logger->debug('getUsers: '.\count($ownCloudUserNames). ' Users found', ['app' => self::class]);
 
-		return $ownCloudUserNames;
+		$this->logger->debug('getLdapUsers: '.\count($ldap_users). ' Users found', ['app' => self::class]);
+		return $ldap_users;
 	}
 
 	// TODO find better places for the delegations to Access

lib/UserSyncLDAPBackend.php

@@ -0,0 +1,199 @@
+<?php
+/**
+ * @copyright Copyright (c) 2023, ownCloud GmbH.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\User_LDAP;
+
+use OC\ServerNotAvailableException;
+use OCA\User_LDAP\Exceptions\BindFailedException;
+use OCA\User_LDAP\User_Proxy;
+use OCP\UserInterface;
+use OCP\Sync\User\IUserSyncBackend;
+use OCP\Sync\User\SyncingUser;
+use OCP\Sync\User\SyncBackendUserFailedException;
+use OCP\Sync\User\SyncBackendBrokenException;
+
+class UserSyncLDAPBackend implements IUserSyncBackend {
+	/** @var User_Proxy */
+	private $userProxy;
+
+	private $connectionTested = false;
+	private $pointer = 0;
+	private $cachedUserData = ['min' => 0, 'max' => 0, 'last' => false];
+
+	public function __construct(User_Proxy $userProxy) {
+		$this->userProxy = $userProxy;
+	}
+
+	/**
+	 * Get the pointer's position. This method isn't part of the interface and
+	 * it's expected to be used only for testing
+	 */
+	public function getPointer() {
+		return $this->pointer;
+	}
+
+	/**
+	 * Get the cached user data. This method isn't part of the interface and
+	 * it's expected to be used only for testing
+	 */
+	public function getCachedUserData() {
+		return $this->cachedUserData;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function resetPointer() {
+		$this->connectionTested = false;
+		$this->pointer = 0;
+		$this->cachedUserData = ['min' => 0, 'max' => 0, 'last' => false];
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getNextUser(): ?SyncingUser {
+		$chunk = 500; // TODO: this should depend on the actual configuration
+		$minPointer = $this->cachedUserData['min'];
+		if (!isset($this->cachedUserData['users'][$this->pointer - $minPointer])) {
+			if ($this->cachedUserData['last']) {
+				// we've reached the end
+				return null;
+			}
+
+			try {
+				if (!$this->connectionTested) {
+					$test = $this->userProxy->testConnection();
+					$this->connectionTested = true;
+				}
+				$ldap_entries = $this->userProxy->getRawUsersEntriesWithPrefix('', $chunk, $this->pointer);
+			} catch (ServerNotAvailableException | BindFailedException $ex) {
+				throw new SyncBackendBrokenException('Failed to get user entries', 1, $ex);
+			}
+
+			$minPointer = $this->pointer;
+			$this->cachedUserData = [
+				'min' => $this->pointer,
+				'max' => $this->pointer + \count($ldap_entries),
+				'last' => empty($ldap_entries),
+				'users' => $ldap_entries,
+			];
+		}
+
+		$syncingUser = null;
+		if (isset($this->cachedUserData['users'][$this->pointer - $minPointer])) {
+			$ldapEntryData = $this->cachedUserData['users'][$this->pointer - $minPointer];
+			$this->pointer++;
+			try {
+				$userEntry = $this->userProxy->getUserEntryFromRawWithPrefix($ldapEntryData['prefix'], $ldapEntryData['entry']);
+			} catch (\OutOfBoundsException $ex) {
+				throw new SyncBackendUserFailedException("Failed to get user with dn {$ldapEntryData['entry']['dn'][0]}", 1, $ex);
+			}
+
+			try {
+				$uid = $userEntry->getOwnCloudUID();
+				$displayname = $userEntry->getDisplayName();
+				$quota = $userEntry->getQuota();
+				$email = $userEntry->getEMailAddress();
+				$home = $userEntry->getHome();
+				$searchTerms = $userEntry->getSearchTerms();
+			} catch (\Exception $ex) {
+				throw new SyncBackendUserFailedException("Can't sync user with dn {$userEntry->getDN()}", 1, $ex);
+			}
+
+			$syncingUser = new SyncingUser($uid);
+			$syncingUser->setDisplayName($displayname);
+			if ($email !== null) {
+				$syncingUser->setEmail($email);
+			}
+			if ($home !== null) {
+				$syncingUser->setHome($home);
+			}
+			if ($searchTerms !== null) {
+				$syncingUser->setSearchTerms($searchTerms);
+			}
+			if ($quota !== false) {
+				$syncingUser->setQuota($quota);
+			}
+		} else {
+			$this->pointer++;
+		}
+		return $syncingUser;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getSyncingUser(string $id): ?SyncingUser {
+		$syncingUser = null;
+
+		try {
+			$userEntry = $this->userProxy->getUserEntry($id);
+		} catch (ServerNotAvailableException | BindFailedException $ex) {
+			throw new SyncBackendBrokenException('Failed to get the user entry', 1, $ex);
+		}
+
+		if ($userEntry !== null) {
+			try {
+				$uid = $userEntry->getOwnCloudUID();
+				$displayname = $userEntry->getDisplayName();
+				$quota = $userEntry->getQuota();
+				$email = $userEntry->getEMailAddress();
+				$home = $userEntry->getHome();
+				$searchTerms = $userEntry->getSearchTerms();
+			} catch (\Exception $ex) {
+				throw new SyncBackendUserFailedException("Can't sync user with dn {$userEntry->getDN()}", 1, $ex);
+			}
+
+			$syncingUser = new SyncingUser($uid);
+			$syncingUser->setDisplayName($displayname);
+			if ($email !== null) {
+				$syncingUser->setEmail($email);
+			}
+			if ($home !== null) {
+				$syncingUser->setHome($home);
+			}
+			if ($searchTerms !== null) {
+				$syncingUser->setSearchTerms($searchTerms);
+			}
+			if ($quota !== false) {
+				$syncingUser->setQuota($quota);
+			}
+		}
+		return $syncingUser;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function userCount(): ?int {
+		$nUsers = $this->userProxy->countUsers();
+		if ($nUsers !== false) {
+			return $nUsers;
+		}
+		return null;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getUserInterface(): UserInterface {
+		return $this->userProxy;
+	}
+}

lib/User_LDAP.php

@@ -178,6 +178,24 @@ public function getUsers($search = '', $limit = 10, $offset = 0) {
 		return $this->userManager->getUsers($search, $limit, $offset);
 	}
 
+	/**
+	 * Get a raw list of users, as returned by the ldap library
+	 *
+	 * WARNING: Using this function combined with LIMIT $limit and OFFSET $offset
+	 * will search in parallel all provided base DNs in this server,
+	 * and thus can return more then LIMIT $limit users. This function shall
+	 * be used with limit and offset by iterators that can
+	 * support this kind of parallel paging.
+	 *
+	 * @param string $search
+	 * @param integer $limit
+	 * @param integer $offset
+	 * @return array an array with the ldap users, as returned by the ldap library
+	 */
+	public function getRawUserEntries($search = '', $limit = 10, $offset = 0) {
+		return $this->userManager->getLdapUsers($search, $limit, $offset);
+	}
+
 	/**
 	 * check if a user exists
 	 *
@@ -406,6 +424,43 @@ public function getAvatar($uid) {
 		return null;
 	}
 
+	/**
+	 * Get a user entry from the provided uid.
+	 *
+	 * @param string $uid
+	 * @return UserEntry|false the user entry, or false if it's missing
+	 */
+	public function getUserEntry($uid) {
+		$userEntry = $this->userManager->getCachedEntry($uid);
+		if ($userEntry === null) {
+			return false;
+		}
+		return $userEntry;
+	}
+
+	/**
+	 * Get a user entry from the raw ldap user data
+	 *
+	 * @param array $ldap_entry
+	 * @return UserEntry the user entry, or false if it's missing
+	 * @throws \BadMethodCallException when access object has not been set
+	 * @throws \InvalidArgumentException if entry does not contain a dn
+	 * @throws \OutOfBoundsException when username could not be determined
+	 */
+	public function getUserEntryFromRaw($ldap_entry) {
+		return $this->userManager->getFromEntry($ldap_entry);
+	}
+
+	/**
+	 * Test the connection by sending a bind request
+	 *
+	 * @return bool true if binds, false otherwise
+	 * @throws \OC\ServerNotAvailableException
+	 */
+	public function testConnection() {
+		return $this->userManager->getConnection()->bind();
+	}
+
 	public function clearConnectionCache() {
 		$this->userManager->getConnection()->clearCache();
 	}