log Flow activity

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>

apps/workflowengine/appinfo/info.xml

@@ -25,6 +25,10 @@
 		<nextcloud min-version="19" max-version="19"/>
 	</dependencies>
 
+	<background-jobs>
+		<job>OCA\WorkflowEngine\BackgroundJobs\Rotate</job>
+	</background-jobs>
+
 	<repair-steps>
 		<post-migration>
 			<step>OCA\WorkflowEngine\Migration\PopulateNewlyIntroducedDatabaseFields</step>

apps/workflowengine/composer/composer/autoload_classmap.php

@@ -7,6 +7,7 @@ $baseDir = $vendorDir;
 
 return array(
     'OCA\\WorkflowEngine\\AppInfo\\Application' => $baseDir . '/../lib/AppInfo/Application.php',
+    'OCA\\WorkflowEngine\\BackgroundJobs\\Rotate' => $baseDir . '/../lib/BackgroundJobs/Rotate.php',
     'OCA\\WorkflowEngine\\Check\\AbstractStringCheck' => $baseDir . '/../lib/Check/AbstractStringCheck.php',
     'OCA\\WorkflowEngine\\Check\\FileMimeType' => $baseDir . '/../lib/Check/FileMimeType.php',
     'OCA\\WorkflowEngine\\Check\\FileName' => $baseDir . '/../lib/Check/FileName.php',
@@ -24,10 +25,12 @@ return array(
     'OCA\\WorkflowEngine\\Controller\\RequestTime' => $baseDir . '/../lib/Controller/RequestTime.php',
     'OCA\\WorkflowEngine\\Controller\\UserWorkflowsController' => $baseDir . '/../lib/Controller/UserWorkflowsController.php',
     'OCA\\WorkflowEngine\\Entity\\File' => $baseDir . '/../lib/Entity/File.php',
+    'OCA\\WorkflowEngine\\Helper\\LogContext' => $baseDir . '/../lib/Helper/LogContext.php',
     'OCA\\WorkflowEngine\\Helper\\ScopeContext' => $baseDir . '/../lib/Helper/ScopeContext.php',
     'OCA\\WorkflowEngine\\Manager' => $baseDir . '/../lib/Manager.php',
     'OCA\\WorkflowEngine\\Migration\\PopulateNewlyIntroducedDatabaseFields' => $baseDir . '/../lib/Migration/PopulateNewlyIntroducedDatabaseFields.php',
     'OCA\\WorkflowEngine\\Migration\\Version2000Date20190808074233' => $baseDir . '/../lib/Migration/Version2000Date20190808074233.php',
+    'OCA\\WorkflowEngine\\Service\\Logger' => $baseDir . '/../lib/Service/Logger.php',
     'OCA\\WorkflowEngine\\Service\\RuleMatcher' => $baseDir . '/../lib/Service/RuleMatcher.php',
     'OCA\\WorkflowEngine\\Settings\\ASettings' => $baseDir . '/../lib/Settings/ASettings.php',
     'OCA\\WorkflowEngine\\Settings\\Admin' => $baseDir . '/../lib/Settings/Admin.php',

apps/workflowengine/composer/composer/autoload_static.php

@@ -22,6 +22,7 @@ class ComposerStaticInitWorkflowEngine
 
     public static $classMap = array (
         'OCA\\WorkflowEngine\\AppInfo\\Application' => __DIR__ . '/..' . '/../lib/AppInfo/Application.php',
+        'OCA\\WorkflowEngine\\BackgroundJobs\\Rotate' => __DIR__ . '/..' . '/../lib/BackgroundJobs/Rotate.php',
         'OCA\\WorkflowEngine\\Check\\AbstractStringCheck' => __DIR__ . '/..' . '/../lib/Check/AbstractStringCheck.php',
         'OCA\\WorkflowEngine\\Check\\FileMimeType' => __DIR__ . '/..' . '/../lib/Check/FileMimeType.php',
         'OCA\\WorkflowEngine\\Check\\FileName' => __DIR__ . '/..' . '/../lib/Check/FileName.php',
@@ -39,10 +40,12 @@ class ComposerStaticInitWorkflowEngine
         'OCA\\WorkflowEngine\\Controller\\RequestTime' => __DIR__ . '/..' . '/../lib/Controller/RequestTime.php',
         'OCA\\WorkflowEngine\\Controller\\UserWorkflowsController' => __DIR__ . '/..' . '/../lib/Controller/UserWorkflowsController.php',
         'OCA\\WorkflowEngine\\Entity\\File' => __DIR__ . '/..' . '/../lib/Entity/File.php',
+        'OCA\\WorkflowEngine\\Helper\\LogContext' => __DIR__ . '/..' . '/../lib/Helper/LogContext.php',
         'OCA\\WorkflowEngine\\Helper\\ScopeContext' => __DIR__ . '/..' . '/../lib/Helper/ScopeContext.php',
         'OCA\\WorkflowEngine\\Manager' => __DIR__ . '/..' . '/../lib/Manager.php',
         'OCA\\WorkflowEngine\\Migration\\PopulateNewlyIntroducedDatabaseFields' => __DIR__ . '/..' . '/../lib/Migration/PopulateNewlyIntroducedDatabaseFields.php',
         'OCA\\WorkflowEngine\\Migration\\Version2000Date20190808074233' => __DIR__ . '/..' . '/../lib/Migration/Version2000Date20190808074233.php',
+        'OCA\\WorkflowEngine\\Service\\Logger' => __DIR__ . '/..' . '/../lib/Service/Logger.php',
         'OCA\\WorkflowEngine\\Service\\RuleMatcher' => __DIR__ . '/..' . '/../lib/Service/RuleMatcher.php',
         'OCA\\WorkflowEngine\\Settings\\ASettings' => __DIR__ . '/..' . '/../lib/Settings/ASettings.php',
         'OCA\\WorkflowEngine\\Settings\\Admin' => __DIR__ . '/..' . '/../lib/Settings/Admin.php',

apps/workflowengine/lib/AppInfo/Application.php

@@ -22,7 +22,9 @@
 namespace OCA\WorkflowEngine\AppInfo;
 
 use OCA\WorkflowEngine\Controller\RequestTime;
+use OCA\WorkflowEngine\Helper\LogContext;
 use OCA\WorkflowEngine\Manager;
+use OCA\WorkflowEngine\Service\Logger;
 use OCP\AppFramework\QueryException;
 use OCP\EventDispatcher\Event;
 use OCP\Template;
@@ -97,6 +99,16 @@ class Application extends \OCP\AppFramework\App {
 								$ruleMatcher->setEntity($entity);
 								$ruleMatcher->setOperation($operation);
 
+								$ctx = new LogContext();
+								$ctx
+									->setOperation($operation)
+									->setEntity($entity)
+									->setEventName($eventName);
+
+								/** @var Logger $flowLogger */
+								$flowLogger = $this->getContainer()->query(Logger::class);
+								$flowLogger->logEventInit($ctx);
+
 								if ($event instanceof Event) {
 									$entity->prepareRuleMatcher($ruleMatcher, $eventName, $event);
 									$operation->onEvent($eventName, $event, $ruleMatcher);
@@ -117,6 +129,7 @@ class Application extends \OCP\AppFramework\App {
 										]
 									);
 								}
+								$flowLogger->logEventDone($ctx);
 
 							} catch (QueryException $e) {
 								// Ignore query exceptions since they might occur when an entity/operation were setup before by an app that is disabled now
@@ -126,5 +139,7 @@ class Application extends \OCP\AppFramework\App {
 				}, $eventNames ?? []);
 			}
 		}
+
+
 	}
 }

apps/workflowengine/lib/BackgroundJobs/Rotate.php

+<?php
+/**
+ * @copyright Copyright (c) 2018 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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/>.
+ *
+ */
+
+namespace OCA\WorkflowEngine\BackgroundJobs;
+
+use OC\BackgroundJob\TimedJob;
+use OCA\WorkflowEngine\AppInfo\Application;
+use OCP\Log\RotationTrait;
+
+class Rotate extends TimedJob {
+	use RotationTrait;
+
+	public function __construct() {
+		$this->setInterval(60*60*3);
+	}
+
+	protected function run($argument) {
+		$config = \OC::$server->getConfig();
+		$default = $config->getSystemValue('datadirectory', \OC::$SERVERROOT . '/data') . '/flow.log';
+		$this->filePath = trim((string)$config->getAppValue(Application::APP_ID, 'logfile', $default));
+
+		if($this->filePath === '') {
+			// disabled, nothing to do
+			return;
+		}
+
+		$this->maxSize = $config->getSystemValue('log_rotate_size', 100 * 1024 * 1024);
+
+		if($this->shouldRotateBySize()) {
+			$this->rotate();
+		}
+	}
+}

apps/workflowengine/lib/Helper/LogContext.php

+<?php
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2019 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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/>.
+ *
+ */
+
+namespace OCA\WorkflowEngine\Helper;
+
+use OCP\WorkflowEngine\IEntity;
+use OCP\WorkflowEngine\IManager;
+use OCP\WorkflowEngine\IOperation;
+
+class LogContext {
+	/** @var array */
+	protected $details;
+
+	public function setDescription(string $description): LogContext {
+		$this->details['description'] = $description;
+		return $this;
+	}
+
+	public function setScopes(array $scopes): LogContext {
+		$this->details['scopes'] = [];
+		foreach ($scopes as $scope) {
+			if($scope instanceof ScopeContext) {
+				switch($scope->getScope()) {
+					case IManager::SCOPE_ADMIN:
+						$this->details['scopes'][] = ['scope' => 'admin'];
+						break;
+					case IManager::SCOPE_USER:
+						$this->details['scopes'][] = [
+							'scope' => 'user',
+							'uid' => $scope->getScopeId(),
+						];
+						break;
+					default:
+						continue;
+				}
+			}
+		}
+		return $this;
+	}
+
+	public function setOperation(?IOperation $operation): LogContext {
+		if($operation instanceof IOperation) {
+			$this->details['operation'] = [
+				'class' => get_class($operation),
+				'name' => $operation->getDisplayName(),
+			];
+		}
+		return $this;
+	}
+
+	public function setEntity(?IEntity $entity): LogContext {
+		if($entity instanceof IEntity) {
+			$this->details['entity'] = [
+				'class' => get_class($entity),
+				'name' => $entity->getName(),
+			];
+		}
+		return $this;
+	}
+
+	public function setConfiguration(array $configuration): LogContext {
+		$this->details['configuration'] = $configuration;
+		return $this;
+	}
+
+	public function setEventName(string $eventName): LogContext {
+		$this->details['eventName'] = $eventName;
+		return $this;
+	}
+
+	public function getDetails(): array {
+		return $this->details;
+	}
+}

apps/workflowengine/lib/Manager.php

@@ -34,6 +34,7 @@ use OCA\WorkflowEngine\Check\RequestUserAgent;
 use OCA\WorkflowEngine\Check\UserGroupMembership;
 use OCA\WorkflowEngine\Entity\File;
 use OCA\WorkflowEngine\Helper\ScopeContext;
+use OCA\WorkflowEngine\Service\Logger;
 use OCA\WorkflowEngine\Service\RuleMatcher;
 use OCP\AppFramework\QueryException;
 use OCP\DB\QueryBuilder\IQueryBuilder;
@@ -127,7 +128,13 @@ class Manager implements IManager {
 	}
 
 	public function getRuleMatcher(): IRuleMatcher {
-		return new RuleMatcher($this->session, $this->container, $this->l, $this);
+		return new RuleMatcher(
+			$this->session,
+			$this->container,
+			$this->l,
+			$this,
+			$this->container->query(Logger::class)
+		);
 	}
 
 	public function getAllConfiguredEvents() {

apps/workflowengine/lib/Service/Logger.php

+<?php
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2020 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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/>.
+ *
+ */
+
+namespace OCA\WorkflowEngine\Service;
+
+use OCA\WorkflowEngine\AppInfo\Application;
+use OCA\WorkflowEngine\Helper\LogContext;
+use OCP\IConfig;
+use OCP\ILogger;
+use OCP\Log\IDataLogger;
+use OCP\Log\ILogFactory;
+
+class Logger {
+	/** @var ILogger */
+	protected $generalLogger;
+	/** @var ILogger */
+	protected $flowLogger;
+	/** @var IConfig */
+	private $config;
+	/** @var ILogFactory */
+	private $logFactory;
+
+	public function __construct(ILogger $generalLogger, IConfig $config, ILogFactory $logFactory) {
+		$this->generalLogger = $generalLogger;
+		$this->config = $config;
+		$this->logFactory = $logFactory;
+
+		$this->initLogger();
+	}
+
+	protected function initLogger() {
+		$default = $this->config->getSystemValue('datadirectory', \OC::$SERVERROOT . '/data') . '/flow.log';
+		$logFile = trim((string)$this->config->getAppValue(Application::APP_ID, 'logfile', $default));
+		if($logFile !== '') {
+			$this->flowLogger = $this->logFactory->getCustomLogger($logFile);
+		}
+	}
+
+	public function logFlowRequests(LogContext $logContext) {
+		$message = 'Flow activation: rules were requested for operation {op}';
+		$context = ['op' => $logContext->getDetails()['operation']['name']];
+
+		$logContext->setDescription('Flow activation: rules were requested');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logScopeExpansion(LogContext $logContext) {
+		$message = 'Flow rule of a different user is legit for operation {op}';
+		$context = ['op' => $logContext->getDetails()['operation']['name']];
+
+		$logContext->setDescription('Flow rule of a different user is legit');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logPassedCheck(LogContext $logContext) {
+		$message = 'Flow rule qualified to run {op}, config: {config}';
+		$context = [
+			'op' => $logContext->getDetails()['operation']['name'],
+			'config' => $logContext->getDetails()['configuration'],
+		];
+
+		$logContext->setDescription('Flow rule qualified to run');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logRunSingle(LogContext $logContext) {
+		$message = 'Last qualified flow configuration is going to run {op}';
+		$context = [
+			'op' => $logContext->getDetails()['operation']['name'],
+		];
+
+		$logContext->setDescription('Last qualified flow configuration is going to run');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logRunAll(LogContext $logContext) {
+		$message = 'All qualified flow configurations are going to run {op}';
+		$context = [
+			'op' => $logContext->getDetails()['operation']['name'],
+		];
+
+		$logContext->setDescription('All qualified flow configurations are going to run');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logRunNone(LogContext $logContext) {
+		$message = 'No flow configurations is going to run {op}';
+		$context = [
+			'op' => $logContext->getDetails()['operation']['name'],
+		];
+
+		$logContext->setDescription('No flow configurations is going to run');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logEventInit(LogContext $logContext) {
+		$message = 'Flow activated by event {ev}';
+
+		$context = [
+			'ev' => $logContext->getDetails()['eventName'],
+		];
+
+		$logContext->setDescription('Flow activated by event');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	public function logEventDone(LogContext $logContext) {
+		$message = 'Flow handling done for event {ev}';
+
+		$context = [
+			'ev' => $logContext->getDetails()['eventName'],
+		];
+
+		$logContext->setDescription('Flow handling for event done');
+
+		$this->log($message, $context, $logContext);
+	}
+
+	protected function log(
+		string $message,
+		array $context,
+		LogContext $logContext
+	): void
+	{
+		if(!isset($context['app'])) {
+			$context['app'] = Application::APP_ID;
+		}
+		if(!isset($context['level'])) {
+			$context['level'] = ILogger::INFO;
+		}
+		$this->generalLogger->log($context['level'], $message, $context);
+
+		if(!$this->flowLogger instanceof IDataLogger) {
+			return;
+		}
+
+		$this->flowLogger->logData(
+			$logContext->getDetails(),
+			['app' => Application::APP_ID, 'level' => $context['level']]
+		);
+	}
+}

apps/workflowengine/lib/Service/RuleMatcher.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 
 namespace OCA\WorkflowEngine\Service;
 
+use OCA\WorkflowEngine\Helper\LogContext;
 use OCA\WorkflowEngine\Helper\ScopeContext;
 use OCA\WorkflowEngine\Manager;
 use OCP\AppFramework\QueryException;
@@ -58,17 +59,21 @@ class RuleMatcher implements IRuleMatcher {
 	protected $operation;
 	/** @var IEntity */
 	protected $entity;
+	/** @var Logger */
+	protected $logger;
 
 	public function __construct(
 		IUserSession $session,
 		IServerContainer $container,
 		IL10N $l,
-		Manager $manager
+		Manager $manager,
+		Logger $logger
 	) {
 		$this->session = $session;
 		$this->manager = $manager;
 		$this->container = $container;
 		$this->l = $l;
+		$this->logger = $logger;
 	}
 
 	public function setFileInfo(IStorage $storage, string $path, bool $isDir = false): void {
@@ -116,6 +121,13 @@ class RuleMatcher implements IRuleMatcher {
 			$scopes[] = new ScopeContext(IManager::SCOPE_USER, $user->getUID());
 		}
 
+		$ctx = new LogContext();
+		$ctx
+			->setScopes($scopes)
+			->setEntity($this->entity)
+			->setOperation($this->operation);
+		$this->logger->logFlowRequests($ctx);
+
 		$operations = [];
 		foreach ($scopes as $scope) {
 			$operations = array_merge($operations, $this->manager->getOperations($class, $scope));
@@ -129,6 +141,12 @@ class RuleMatcher implements IRuleMatcher {
 					continue;
 				}
 				if ($this->entity->isLegitimatedForUserId($scopeCandidate->getScopeId())) {
+					$ctx = new LogContext();
+					$ctx
+						->setScopes($scopeCandidate)
+						->setEntity($this->entity)
+						->setOperation($this->operation);
+					$this->logger->logScopeExpansion($ctx);
 					$operations = array_merge($operations, $this->manager->getOperations($class, $scopeCandidate));
 				}
 			}
@@ -146,12 +164,36 @@ class RuleMatcher implements IRuleMatcher {
 				}
 			}
 
+			$ctx = new LogContext();
+			$ctx
+				->setEntity($this->entity)
+				->setOperation($this->operation)
+				->setConfiguration($operation);
+			$this->logger->logPassedCheck($ctx);
+
 			if ($returnFirstMatchingOperationOnly) {
+				$ctx = new LogContext();
+				$ctx
+					->setEntity($this->entity)
+					->setOperation($this->operation)
+					->setConfiguration($operation);
+				$this->logger->logRunSingle($ctx);
 				return $operation;
 			}
 			$matches[] = $operation;
 		}
 
+		$ctx = new LogContext();
+		$ctx
+			->setEntity($this->entity)
+			->setOperation($this->operation);
+		if(!empty($matches)) {
+			$ctx->setConfiguration($matches);
+			$this->logger->logRunAll($ctx);
+		} else {
+			$this->logger->logRunNone($ctx);
+		}
+
 		return $matches;
 	}
 
@@ -183,4 +225,10 @@ class RuleMatcher implements IRuleMatcher {
 		}
 		return $checkInstance->executeCheck($check['operator'], $check['value']);
 	}
+
+	protected function logCandidate() {
+		$logContext = new LogContext();
+		$logContext
+			->setOperation();
+	}
 }

lib/composer/composer/autoload_classmap.php

@@ -367,6 +367,7 @@ return array(
     'OCP\\Lock\\LockedException' => $baseDir . '/lib/public/Lock/LockedException.php',
     'OCP\\Lock\\ManuallyLockedException' => $baseDir . '/lib/public/Lock/ManuallyLockedException.php',
     'OCP\\Lockdown\\ILockdownManager' => $baseDir . '/lib/public/Lockdown/ILockdownManager.php',
+    'OCP\\Log\\IDataLogger' => $baseDir . '/lib/public/Log/IDataLogger.php',
     'OCP\\Log\\IFileBased' => $baseDir . '/lib/public/Log/IFileBased.php',
     'OCP\\Log\\ILogFactory' => $baseDir . '/lib/public/Log/ILogFactory.php',
     'OCP\\Log\\IWriter' => $baseDir . '/lib/public/Log/IWriter.php',

lib/composer/composer/autoload_static.php

@@ -396,6 +396,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OCP\\Lock\\LockedException' => __DIR__ . '/../../..' . '/lib/public/Lock/LockedException.php',
         'OCP\\Lock\\ManuallyLockedException' => __DIR__ . '/../../..' . '/lib/public/Lock/ManuallyLockedException.php',
         'OCP\\Lockdown\\ILockdownManager' => __DIR__ . '/../../..' . '/lib/public/Lockdown/ILockdownManager.php',
+        'OCP\\Log\\IDataLogger' => __DIR__ . '/../../..' . '/lib/public/Log/IDataLogger.php',
         'OCP\\Log\\IFileBased' => __DIR__ . '/../../..' . '/lib/public/Log/IFileBased.php',
         'OCP\\Log\\ILogFactory' => __DIR__ . '/../../..' . '/lib/public/Log/ILogFactory.php',
         'OCP\\Log\\IWriter' => __DIR__ . '/../../..' . '/lib/public/Log/IWriter.php',

lib/private/Log.php

@@ -36,6 +36,7 @@ declare(strict_types=1);
 
 namespace OC;
 
+use OCP\Log\IDataLogger;
 use function array_merge;
 use InterfaSys\LogNormalizer\Normalizer;
 
@@ -54,7 +55,7 @@ use OCP\Support\CrashReport\IRegistry;
  *
  * MonoLog is an example implementing this interface.
  */
-class Log implements ILogger {
+class Log implements ILogger, IDataLogger {
 
 	/** @var IWriter */
 	private $logger;
@@ -339,6 +340,28 @@ class Log implements ILogger {
 		}
 	}
 
+	public function logData(array $data, array $context = []): void {
+		$app = $context['app'] ?? 'no app in context';
+		$level = $context['level'] ?? ILogger::ERROR;
+
+		$minLevel = $this->getLogLevel($context);
+
+		array_walk($context, [$this->normalizer, 'format']);
+
+		try {
+			if ($level >= $minLevel) {
+				if (!$this->logger instanceof IFileBased) {
+					$data = json_encode($data, JSON_PARTIAL_OUTPUT_ON_ERROR | JSON_UNESCAPED_SLASHES);
+				}
+				$this->writeLog($app, $data, $level);
+			}
+
+			$context['level'] = $level;
+		} catch (\Throwable $e) {
+			// make sure we dont hard crash if logging fails
+		}
+	}
+
 	/**
 	 * @param string $app
 	 * @param string|array $entry

lib/public/Log/IDataLogger.php

+<?php
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2019 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @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/>.
+ *
+ */
+
+namespace OCP\Log;
+
+/**
+ * Interface IDataLogger
+ *
+ * @package OCP\Log
+ * @since 18.0.0
+ */
+interface IDataLogger {
+
+	/**
+	 * allows to log custom data, similar to how logException works
+	 *
+	 * @since 18.0.0
+	 */
+	public function logData(array $data, array $context = []): void;
+
+}