Merge pull request #47978 from nextcloud/chore/remove-ilogger

chore!: Remove `ILogger` and its friends 

15 files changed, 71 insertions, 319 deletions

diff --git a/lib/composer/composer/autoload_classmap.php b/lib/composer/composer/autoload_classmap.php
index 578395a45b4..82964a6e6c7 100644
--- a/lib/composer/composer/autoload_classmap.php
+++ b/lib/composer/composer/autoload_classmap.php
@@ -931,7 +931,6 @@ return array(
     'OC\\AppFramework\\Http\\Output' => $baseDir . '/lib/private/AppFramework/Http/Output.php',
     'OC\\AppFramework\\Http\\Request' => $baseDir . '/lib/private/AppFramework/Http/Request.php',
     'OC\\AppFramework\\Http\\RequestId' => $baseDir . '/lib/private/AppFramework/Http/RequestId.php',
-    'OC\\AppFramework\\Logger' => $baseDir . '/lib/private/AppFramework/Logger.php',
     'OC\\AppFramework\\Middleware\\AdditionalScriptsMiddleware' => $baseDir . '/lib/private/AppFramework/Middleware/AdditionalScriptsMiddleware.php',
     'OC\\AppFramework\\Middleware\\CompressionMiddleware' => $baseDir . '/lib/private/AppFramework/Middleware/CompressionMiddleware.php',
     'OC\\AppFramework\\Middleware\\MiddlewareDispatcher' => $baseDir . '/lib/private/AppFramework/Middleware/MiddlewareDispatcher.php',
diff --git a/lib/composer/composer/autoload_static.php b/lib/composer/composer/autoload_static.php
index 2e507ec7a5f..d83229c7426 100644
--- a/lib/composer/composer/autoload_static.php
+++ b/lib/composer/composer/autoload_static.php
@@ -964,7 +964,6 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OC\\AppFramework\\Http\\Output' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Http/Output.php',
         'OC\\AppFramework\\Http\\Request' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Http/Request.php',
         'OC\\AppFramework\\Http\\RequestId' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Http/RequestId.php',
-        'OC\\AppFramework\\Logger' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Logger.php',
         'OC\\AppFramework\\Middleware\\AdditionalScriptsMiddleware' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Middleware/AdditionalScriptsMiddleware.php',
         'OC\\AppFramework\\Middleware\\CompressionMiddleware' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Middleware/CompressionMiddleware.php',
         'OC\\AppFramework\\Middleware\\MiddlewareDispatcher' => __DIR__ . '/../../..' . '/lib/private/AppFramework/Middleware/MiddlewareDispatcher.php',
diff --git a/lib/private/AppFramework/DependencyInjection/DIContainer.php b/lib/private/AppFramework/DependencyInjection/DIContainer.php
index a96e050c0e6..0b87fea127e 100644
--- a/lib/private/AppFramework/DependencyInjection/DIContainer.php
+++ b/lib/private/AppFramework/DependencyInjection/DIContainer.php
@@ -39,7 +39,6 @@ use OCP\IDBConnection;
 use OCP\IGroupManager;
 use OCP\IInitialStateService;
 use OCP\IL10N;
-use OCP\ILogger;
 use OCP\INavigationManager;
 use OCP\IRequest;
 use OCP\IServerContainer;
@@ -120,9 +119,6 @@ class DIContainer extends SimpleContainer implements IAppContainer {
 				$c->get('AppName')
 			);
 		});
-		$this->registerService(ILogger::class, function (ContainerInterface $c) {
-			return new OC\AppFramework\Logger($this->server->query(ILogger::class), $c->get('AppName'));
-		});
 
 		$this->registerService(IServerContainer::class, function () {
 			return $this->getServer();
diff --git a/lib/private/AppFramework/Logger.php b/lib/private/AppFramework/Logger.php
deleted file mode 100644
index 4ae4e6cae34..00000000000
--- a/lib/private/AppFramework/Logger.php
+++ /dev/null
@@ -1,108 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-/**
- * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
- * SPDX-License-Identifier: AGPL-3.0-or-later
- */
-namespace OC\AppFramework;
-
-use OCP\ILogger;
-
-/**
- * @deprecated
- */
-class Logger implements ILogger {
-	/** @var ILogger */
-	private $logger;
-
-	/** @var string */
-	private $appName;
-
-	/**
-	 * @deprecated
-	 */
-	public function __construct(ILogger $logger, string $appName) {
-		$this->logger = $logger;
-		$this->appName = $appName;
-	}
-
-	private function extendContext(array $context): array {
-		if (!isset($context['app'])) {
-			$context['app'] = $this->appName;
-		}
-
-		return $context;
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function emergency(string $message, array $context = []) {
-		$this->logger->emergency($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function alert(string $message, array $context = []) {
-		$this->logger->alert($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function critical(string $message, array $context = []) {
-		$this->logger->critical($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function error(string $message, array $context = []) {
-		$this->logger->emergency($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function warning(string $message, array $context = []) {
-		$this->logger->warning($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function notice(string $message, array $context = []) {
-		$this->logger->notice($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function info(string $message, array $context = []) {
-		$this->logger->info($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function debug(string $message, array $context = []) {
-		$this->logger->debug($message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function log(int $level, string $message, array $context = []) {
-		$this->logger->log($level, $message, $this->extendContext($context));
-	}
-
-	/**
-	 * @deprecated
-	 */
-	public function logException(\Throwable $exception, array $context = []) {
-		$this->logger->logException($exception, $this->extendContext($context));
-	}
-}
diff --git a/lib/private/Collaboration/AutoComplete/Manager.php b/lib/private/Collaboration/AutoComplete/Manager.php
index 382b9188535..c4dd4093e69 100644
--- a/lib/private/Collaboration/AutoComplete/Manager.php
+++ b/lib/private/Collaboration/AutoComplete/Manager.php
@@ -7,7 +7,9 @@ namespace OC\Collaboration\AutoComplete;
 
 use OCP\Collaboration\AutoComplete\IManager;
 use OCP\Collaboration\AutoComplete\ISorter;
-use OCP\IServerContainer;
+use Psr\Container\ContainerExceptionInterface;
+use Psr\Container\ContainerInterface;
+use Psr\Log\LoggerInterface;
 
 class Manager implements IManager {
 	/** @var string[] */
@@ -17,7 +19,8 @@ class Manager implements IManager {
 	protected array $sorterInstances = [];
 
 	public function __construct(
-		private IServerContainer $container,
+		private ContainerInterface $container,
+		private LoggerInterface $logger,
 	) {
 	}
 
@@ -27,7 +30,7 @@ class Manager implements IManager {
 			if (isset($sorterInstances[$sorter])) {
 				$sorterInstances[$sorter]->sort($sortArray, $context);
 			} else {
-				$this->container->getLogger()->warning('No sorter for ID "{id}", skipping', [
+				$this->logger->warning('No sorter for ID "{id}", skipping', [
 					'app' => 'core', 'id' => $sorter
 				]);
 			}
@@ -41,16 +44,23 @@ class Manager implements IManager {
 	protected function getSorters(): array {
 		if (count($this->sorterInstances) === 0) {
 			foreach ($this->sorters as $sorter) {
-				/** @var ISorter $instance */
-				$instance = $this->container->resolve($sorter);
+				try {
+					$instance = $this->container->get($sorter);
+				} catch (ContainerExceptionInterface) {
+					$this->logger->notice(
+						'Skipping not registered sorter. Class name: {class}',
+						['app' => 'core', 'class' => $sorter],
+					);
+					continue;
+				}
 				if (!$instance instanceof ISorter) {
-					$this->container->getLogger()->notice('Skipping sorter which is not an instance of ISorter. Class name: {class}',
+					$this->logger->notice('Skipping sorter which is not an instance of ISorter. Class name: {class}',
 						['app' => 'core', 'class' => $sorter]);
 					continue;
 				}
 				$sorterId = trim($instance->getId());
 				if (trim($sorterId) === '') {
-					$this->container->getLogger()->notice('Skipping sorter with empty ID. Class name: {class}',
+					$this->logger->notice('Skipping sorter with empty ID. Class name: {class}',
 						['app' => 'core', 'class' => $sorter]);
 					continue;
 				}
diff --git a/lib/private/Log/LogFactory.php b/lib/private/Log/LogFactory.php
index a5a7290bd9c..612d98c9746 100644
--- a/lib/private/Log/LogFactory.php
+++ b/lib/private/Log/LogFactory.php
@@ -7,7 +7,6 @@ namespace OC\Log;
 
 use OC\Log;
 use OC\SystemConfig;
-use OCP\ILogger;
 use OCP\IServerContainer;
 use OCP\Log\ILogFactory;
 use OCP\Log\IWriter;
@@ -33,11 +32,6 @@ class LogFactory implements ILogFactory {
 		};
 	}
 
-	public function getCustomLogger(string $path): ILogger {
-		$log = $this->buildLogFile($path);
-		return new Log($log, $this->systemConfig);
-	}
-
 	protected function createNewLogger(string $type, string $tag, string $path): IWriter {
 		return match (strtolower($type)) {
 			'errorlog' => new Errorlog($this->systemConfig, $tag),
diff --git a/lib/private/Server.php b/lib/private/Server.php
index f48cc0d0a48..943b4fc6997 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -177,7 +177,6 @@ use OCP\IEventSourceFactory;
 use OCP\IGroupManager;
 use OCP\IInitialStateService;
 use OCP\IL10N;
-use OCP\ILogger;
 use OCP\INavigationManager;
 use OCP\IPhoneNumberUtil;
 use OCP\IPreview;
@@ -680,6 +679,7 @@ class Server extends ServerContainer implements IServerContainer {
 		$this->registerAlias(\OCP\Support\Subscription\IRegistry::class, \OC\Support\Subscription\Registry::class);
 		$this->registerAlias(\OCP\Support\Subscription\IAssertion::class, \OC\Support\Subscription\Assertion::class);
 
+		/** Only used by the PsrLoggerAdapter should not be used by apps */
 		$this->registerService(\OC\Log::class, function (Server $c) {
 			$logType = $c->get(AllConfig::class)->getSystemValue('log_type', 'file');
 			$factory = new LogFactory($c, $this->get(SystemConfig::class));
@@ -688,7 +688,6 @@ class Server extends ServerContainer implements IServerContainer {
 
 			return new Log($logger, $this->get(SystemConfig::class), crashReporters: $registry);
 		});
-		$this->registerAlias(ILogger::class, \OC\Log::class);
 		// PSR-3 logger
 		$this->registerAlias(LoggerInterface::class, PsrLoggerAdapter::class);
 
@@ -1657,16 +1656,6 @@ class Server extends ServerContainer implements IServerContainer {
 	}
 
 	/**
-	 * Returns a logger instance
-	 *
-	 * @return ILogger
-	 * @deprecated 20.0.0
-	 */
-	public function getLogger() {
-		return $this->get(ILogger::class);
-	}
-
-	/**
 	 * @return ILogFactory
 	 * @throws \OCP\AppFramework\QueryException
 	 * @deprecated 20.0.0
diff --git a/lib/private/Share20/ProviderFactory.php b/lib/private/Share20/ProviderFactory.php
index e1a2c9a5375..7335c863df0 100644
--- a/lib/private/Share20/ProviderFactory.php
+++ b/lib/private/Share20/ProviderFactory.php
@@ -38,8 +38,6 @@ use Psr\Log\LoggerInterface;
  * @package OC\Share20
  */
 class ProviderFactory implements IProviderFactory {
-	/** @var IServerContainer */
-	private $serverContainer;
 	/** @var DefaultShareProvider */
 	private $defaultProvider = null;
 	/** @var FederatedShareProvider */
@@ -62,8 +60,9 @@ class ProviderFactory implements IProviderFactory {
 	 *
 	 * @param IServerContainer $serverContainer
 	 */
-	public function __construct(IServerContainer $serverContainer) {
-		$this->serverContainer = $serverContainer;
+	public function __construct(
+		private IServerContainer $serverContainer,
+	) {
 	}
 
 	public function registerProvider(string $shareProviderClass): void {
@@ -83,10 +82,10 @@ class ProviderFactory implements IProviderFactory {
 				$this->serverContainer->getGroupManager(),
 				$this->serverContainer->get(IRootFolder::class),
 				$this->serverContainer->get(IMailer::class),
-				$this->serverContainer->query(Defaults::class),
+				$this->serverContainer->get(Defaults::class),
 				$this->serverContainer->get(IFactory::class),
 				$this->serverContainer->getURLGenerator(),
-				$this->serverContainer->query(ITimeFactory::class),
+				$this->serverContainer->get(ITimeFactory::class),
 				$this->serverContainer->get(LoggerInterface::class),
 				$this->serverContainer->get(IManager::class),
 			);
@@ -122,11 +121,11 @@ class ProviderFactory implements IProviderFactory {
 			$notifications = new Notifications(
 				$addressHandler,
 				$this->serverContainer->get(IClientService::class),
-				$this->serverContainer->query(\OCP\OCS\IDiscoveryService::class),
+				$this->serverContainer->get(\OCP\OCS\IDiscoveryService::class),
 				$this->serverContainer->getJobList(),
 				\OC::$server->getCloudFederationProviderManager(),
 				\OC::$server->get(ICloudFederationFactory::class),
-				$this->serverContainer->query(IEventDispatcher::class),
+				$this->serverContainer->get(IEventDispatcher::class),
 				$this->serverContainer->get(LoggerInterface::class),
 			);
 			$tokenHandler = new TokenHandler(
@@ -181,7 +180,7 @@ class ProviderFactory implements IProviderFactory {
 				$this->serverContainer->getURLGenerator(),
 				$this->serverContainer->getActivityManager(),
 				$settingsManager,
-				$this->serverContainer->query(Defaults::class),
+				$this->serverContainer->get(Defaults::class),
 				$this->serverContainer->get(IHasher::class),
 				$this->serverContainer->get(IEventDispatcher::class),
 				$this->serverContainer->get(IManager::class)
@@ -218,7 +217,7 @@ class ProviderFactory implements IProviderFactory {
 				$this->serverContainer->getUserManager(),
 				$this->serverContainer->get(IRootFolder::class),
 				$this->serverContainer->getL10N('circles'),
-				$this->serverContainer->getLogger(),
+				$this->serverContainer->get(LoggerInterface::class),
 				$this->serverContainer->getURLGenerator()
 			);
 		}
diff --git a/lib/private/legacy/OC_App.php b/lib/private/legacy/OC_App.php
index 0756f274a11..e5c2c34294d 100644
--- a/lib/private/legacy/OC_App.php
+++ b/lib/private/legacy/OC_App.php
@@ -388,7 +388,7 @@ class OC_App {
 	 * @deprecated 20.0.0 Please register your alternative login option using the registerAlternativeLogin() on the RegistrationContext in your Application class implementing the OCP\Authentication\IAlternativeLogin interface
 	 */
 	public static function registerLogIn(array $entry) {
-		\OC::$server->getLogger()->debug('OC_App::registerLogIn() is deprecated, please register your alternative login option using the registerAlternativeLogin() on the RegistrationContext in your Application class implementing the OCP\Authentication\IAlternativeLogin interface');
+		\OCP\Server::get(LoggerInterface::class)->debug('OC_App::registerLogIn() is deprecated, please register your alternative login option using the registerAlternativeLogin() on the RegistrationContext in your Application class implementing the OCP\Authentication\IAlternativeLogin interface');
 		self::$altLogin[] = $entry;
 	}
 
@@ -401,7 +401,7 @@ class OC_App {
 
 		foreach ($bootstrapCoordinator->getRegistrationContext()->getAlternativeLogins() as $registration) {
 			if (!in_array(IAlternativeLogin::class, class_implements($registration->getService()), true)) {
-				\OC::$server->getLogger()->error('Alternative login option {option} does not implement {interface} and is therefore ignored.', [
+				\OCP\Server::get(LoggerInterface::class)->error('Alternative login option {option} does not implement {interface} and is therefore ignored.', [
 					'option' => $registration->getService(),
 					'interface' => IAlternativeLogin::class,
 					'app' => $registration->getAppId(),
@@ -413,11 +413,12 @@ class OC_App {
 				/** @var IAlternativeLogin $provider */
 				$provider = \OCP\Server::get($registration->getService());
 			} catch (ContainerExceptionInterface $e) {
-				\OC::$server->getLogger()->logException($e, [
-					'message' => 'Alternative login option {option} can not be initialised.',
-					'option' => $registration->getService(),
-					'app' => $registration->getAppId(),
-				]);
+				\OCP\Server::get(LoggerInterface::class)->error('Alternative login option {option} can not be initialized.',
+					[
+						'exception' => $e,
+						'option' => $registration->getService(),
+						'app' => $registration->getAppId(),
+					]);
 			}
 
 			try {
@@ -429,11 +430,12 @@ class OC_App {
 					'class' => $provider->getClass(),
 				];
 			} catch (Throwable $e) {
-				\OC::$server->getLogger()->logException($e, [
-					'message' => 'Alternative login option {option} had an error while loading.',
-					'option' => $registration->getService(),
-					'app' => $registration->getAppId(),
-				]);
+				\OCP\Server::get(LoggerInterface::class)->error('Alternative login option {option} had an error while loading.',
+					[
+						'exception' => $e,
+						'option' => $registration->getService(),
+						'app' => $registration->getAppId(),
+					]);
 			}
 		}
 
@@ -667,7 +669,7 @@ class OC_App {
 		}
 
 		if (is_file($appPath . '/appinfo/database.xml')) {
-			\OC::$server->getLogger()->error('The appinfo/database.xml file is not longer supported. Used in ' . $appId);
+			\OCP\Server::get(LoggerInterface::class)->error('The appinfo/database.xml file is not longer supported. Used in ' . $appId);
 			return false;
 		}
 
diff --git a/lib/private/legacy/OC_Files.php b/lib/private/legacy/OC_Files.php
index 8e23d70c690..126472e3061 100644
--- a/lib/private/legacy/OC_Files.php
+++ b/lib/private/legacy/OC_Files.php
@@ -7,12 +7,14 @@
  */
 use bantu\IniGetWrapper\IniGetWrapper;
 use OC\Files\View;
+use OC\HintException;
 use OC\Streamer;
 use OCP\EventDispatcher\IEventDispatcher;
 use OCP\Files\Events\BeforeDirectFileDownloadEvent;
 use OCP\Files\Events\BeforeZipCreatedEvent;
 use OCP\Files\IRootFolder;
 use OCP\Lock\ILockingProvider;
+use Psr\Log\LoggerInterface;
 
 /**
  * Class for file server access
@@ -165,7 +167,7 @@ class OC_Files {
 							$fileTime = $file->getMTime();
 						} else {
 							// File is not a file? …
-							\OC::$server->getLogger()->debug(
+							\OCP\Server::get(LoggerInterface::class)->debug(
 								'File given, but no Node available. Name {file}',
 								[ 'app' => 'files', 'file' => $file ]
 							);
@@ -186,25 +188,25 @@ class OC_Files {
 			self::unlockAllTheFiles($dir, $files, $getType, $view, $filename);
 		} catch (\OCP\Lock\LockedException $ex) {
 			self::unlockAllTheFiles($dir, $files, $getType, $view, $filename);
-			OC::$server->getLogger()->logException($ex);
+			\OCP\Server::get(LoggerInterface::class)->error('File is currently busy', ['exception' => $ex]);
 			$l = \OC::$server->getL10N('lib');
-			$hint = method_exists($ex, 'getHint') ? $ex->getHint() : '';
+			$hint = $ex instanceof HintException ? $ex->getHint() : '';
 			\OC_Template::printErrorPage($l->t('File is currently busy, please try again later'), $hint, 200);
 		} catch (\OCP\Files\ForbiddenException $ex) {
 			self::unlockAllTheFiles($dir, $files, $getType, $view, $filename);
-			OC::$server->getLogger()->logException($ex);
+			\OCP\Server::get(LoggerInterface::class)->error('Cannot download file', ['exception' => $ex]);
 			$l = \OC::$server->getL10N('lib');
 			\OC_Template::printErrorPage($l->t('Cannot download file'), $ex->getMessage(), 200);
 		} catch (\OCP\Files\ConnectionLostException $ex) {
 			self::unlockAllTheFiles($dir, $files, $getType, $view, $filename);
-			OC::$server->getLogger()->logException($ex, ['level' => \OCP\ILogger::DEBUG]);
+			\OCP\Server::get(LoggerInterface::class)->debug('Connection lost', ['exception' => $ex]);
 			/* We do not print anything here, the connection is already closed */
 			die();
 		} catch (\Exception $ex) {
 			self::unlockAllTheFiles($dir, $files, $getType, $view, $filename);
-			OC::$server->getLogger()->logException($ex);
+			\OCP\Server::get(LoggerInterface::class)->error('Cannot download file', ['exception' => $ex]);
 			$l = \OC::$server->getL10N('lib');
-			$hint = method_exists($ex, 'getHint') ? $ex->getHint() : '';
+			$hint = $ex instanceof HintException ? $ex->getHint() : '';
 			if ($event && $event->getErrorMessage() !== null) {
 				$hint .= ' ' . $event->getErrorMessage();
 			}
diff --git a/lib/private/legacy/OC_Hook.php b/lib/private/legacy/OC_Hook.php
index 5c36a253895..e472b105498 100644
--- a/lib/private/legacy/OC_Hook.php
+++ b/lib/private/legacy/OC_Hook.php
@@ -5,6 +5,9 @@
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
+
+use Psr\Log\LoggerInterface;
+
 class OC_Hook {
 	public static $thrownExceptions = [];
 
@@ -82,7 +85,7 @@ class OC_Hook {
 				call_user_func([ $i['class'], $i['name'] ], $params);
 			} catch (Exception $e) {
 				self::$thrownExceptions[] = $e;
-				\OC::$server->getLogger()->logException($e);
+				\OCP\Server::get(LoggerInterface::class)->error($e->getMessage(), ['exception' => $e]);
 				if ($e instanceof \OCP\HintException) {
 					throw $e;
 				}
diff --git a/lib/private/legacy/OC_Template.php b/lib/private/legacy/OC_Template.php
index 422709cec7d..47803041cb5 100644
--- a/lib/private/legacy/OC_Template.php
+++ b/lib/private/legacy/OC_Template.php
@@ -9,6 +9,7 @@ use OC\TemplateLayout;
 use OCP\AppFramework\Http\Events\BeforeTemplateRenderedEvent;
 use OCP\AppFramework\Http\TemplateResponse;
 use OCP\EventDispatcher\IEventDispatcher;
+use Psr\Log\LoggerInterface;
 
 require_once __DIR__.'/template/functions.php';
 
@@ -242,10 +243,10 @@ class OC_Template extends \OC\Template\Base {
 			\OC::$server->get(IEventDispatcher::class)->dispatchTyped($event);
 			print($response->render());
 		} catch (\Throwable $e1) {
-			$logger = \OC::$server->getLogger();
-			$logger->logException($e1, [
+			$logger = \OCP\Server::get(LoggerInterface::class);
+			$logger->error('Rendering themed error page failed. Falling back to un-themed error page.', [
 				'app' => 'core',
-				'message' => 'Rendering themed error page failed. Falling back to unthemed error page.'
+				'exception' => $e1,
 			]);
 
 			try {
@@ -256,9 +257,9 @@ class OC_Template extends \OC\Template\Base {
 			} catch (\Exception $e2) {
 				// If nothing else works, fall back to plain text error page
 				$logger->error("$error_msg $hint", ['app' => 'core']);
-				$logger->logException($e2, [
+				$logger->error('Rendering un-themed error page failed. Falling back to plain text error page.', [
 					'app' => 'core',
-					'message' => 'Rendering unthemed error page failed. Falling back to plain text error page.'
+					'exception' => $e2,
 				]);
 
 				header('Content-Type: text/plain; charset=utf-8');
@@ -296,9 +297,9 @@ class OC_Template extends \OC\Template\Base {
 			$content->printPage();
 		} catch (\Exception $e) {
 			try {
-				$logger = \OC::$server->getLogger();
-				$logger->logException($exception, ['app' => 'core']);
-				$logger->logException($e, ['app' => 'core']);
+				$logger = \OCP\Server::get(LoggerInterface::class);
+				$logger->error($exception->getMessage(), ['app' => 'core', 'exception' => $exception]);
+				$logger->error($e->getMessage(), ['app' => 'core', 'exception' => $e]);
 			} catch (Throwable $e) {
 				// no way to log it properly - but to avoid a white page of death we send some output
 				self::printPlainErrorPage($e, $debug);
diff --git a/lib/private/legacy/OC_Util.php b/lib/private/legacy/OC_Util.php
index 84bb0b645d5..e152feb639e 100644
--- a/lib/private/legacy/OC_Util.php
+++ b/lib/private/legacy/OC_Util.php
@@ -175,7 +175,7 @@ class OC_Util {
 	 * @return void
 	 */
 	public static function copyr($source, \OCP\Files\Folder $target) {
-		$logger = \OC::$server->getLogger();
+		$logger = \OCP\Server::get(LoggerInterface::class);
 
 		// Verify if folder exists
 		$dir = opendir($source);
@@ -1015,7 +1015,7 @@ class OC_Util {
 
 		$normalizedValue = Normalizer::normalize($value);
 		if ($normalizedValue === null || $normalizedValue === false) {
-			\OC::$server->getLogger()->warning('normalizing failed for "' . $value . '"', ['app' => 'core']);
+			\OCP\Server::get(LoggerInterface::class)->warning('normalizing failed for "' . $value . '"', ['app' => 'core']);
 			return $value;
 		}
 
diff --git a/lib/public/ILogger.php b/lib/public/ILogger.php
index 0716dae07d6..54f9ffeca9a 100644
--- a/lib/public/ILogger.php
+++ b/lib/public/ILogger.php
@@ -9,157 +9,32 @@ declare(strict_types=1);
 namespace OCP;
 
 /**
- * Interface ILogger
- * @since 7.0.0
+ * Nextcloud logging levels.
+ * For historical reasons the logging levels are provided as interface constants.
  *
- * This logger interface follows the design guidelines of PSR-3
- * https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-3-logger-interface.md#3-psrlogloggerinterface
- * @deprecated 20.0.0 use the PSR-3 logger \Psr\Log\LoggerInterface
+ * @since 7.0.0
+ * @since 20.0.0 deprecated logging methods in favor of \Psr\Log\LoggerInterface
+ * @since 31.0.0 removed deprecated logging methods - the interface is kept for Nextcloud log levels
  */
 interface ILogger {
 	/**
 	 * @since 14.0.0
-	 * @deprecated 20.0.0
 	 */
 	public const DEBUG = 0;
 	/**
 	 * @since 14.0.0
-	 * @deprecated 20.0.0
 	 */
 	public const INFO = 1;
 	/**
 	 * @since 14.0.0
-	 * @deprecated 20.0.0
 	 */
 	public const WARN = 2;
 	/**
 	 * @since 14.0.0
-	 * @deprecated 20.0.0
 	 */
 	public const ERROR = 3;
 	/**
 	 * @since 14.0.0
-	 * @deprecated 20.0.0
 	 */
 	public const FATAL = 4;
-
-	/**
-	 * System is unusable.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::emergency
-	 */
-	public function emergency(string $message, array $context = []);
-
-	/**
-	 * Action must be taken immediately.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::alert
-	 */
-	public function alert(string $message, array $context = []);
-
-	/**
-	 * Critical conditions.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::critical
-	 */
-	public function critical(string $message, array $context = []);
-
-	/**
-	 * Runtime errors that do not require immediate action but should typically
-	 * be logged and monitored.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::error
-	 */
-	public function error(string $message, array $context = []);
-
-	/**
-	 * Exceptional occurrences that are not errors.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::warning
-	 */
-	public function warning(string $message, array $context = []);
-
-	/**
-	 * Normal but significant events.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::notice
-	 */
-	public function notice(string $message, array $context = []);
-
-	/**
-	 * Interesting events.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::info
-	 */
-	public function info(string $message, array $context = []);
-
-	/**
-	 * Detailed debug information.
-	 *
-	 * @param string $message
-	 * @param array $context
-	 * @return null
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::debug
-	 */
-	public function debug(string $message, array $context = []);
-
-	/**
-	 * Logs with an arbitrary level.
-	 *
-	 * @param int $level
-	 * @param string $message
-	 * @param array $context
-	 * @return mixed
-	 * @since 7.0.0
-	 * @deprecated 20.0.0 use \Psr\Log\LoggerInterface::log
-	 */
-	public function log(int $level, string $message, array $context = []);
-
-	/**
-	 * Logs an exception very detailed
-	 * An additional message can we written to the log by adding it to the
-	 * context.
-	 *
-	 * <code>
-	 * $logger->logException($ex, [
-	 *     'message' => 'Exception during background job execution'
-	 * ]);
-	 * </code>
-	 *
-	 * @param \Exception|\Throwable $exception
-	 * @param array $context
-	 * @return void
-	 * @since 8.2.0
-	 * @deprecated 20.0.0 use the `exception` entry in the context of any method in \Psr\Log\LoggerInterface
-	 */
-	public function logException(\Throwable $exception, array $context = []);
 }
diff --git a/lib/public/IServerContainer.php b/lib/public/IServerContainer.php
index 027dfcb77c4..82da8779a66 100644
--- a/lib/public/IServerContainer.php
+++ b/lib/public/IServerContainer.php
@@ -317,15 +317,6 @@ interface IServerContainer extends ContainerInterface, IContainer {
 	public function getJobList();
 
 	/**
-	 * Returns a logger instance
-	 *
-	 * @return \OCP\ILogger
-	 * @since 8.0.0
-	 * @deprecated 20.0.0 have it injected or fetch it through \Psr\Container\ContainerInterface::get
-	 */
-	public function getLogger();
-
-	/**
 	 * returns a log factory instance
 	 *
 	 * @return ILogFactory