Merge pull request #19890 from nextcloud/enh/comments-reference-id

Add optional comments reference_id

apps/dav/tests/unit/Comments/CommentsNodeTest.php

@@ -108,7 +108,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->node->delete();
 	}
 
-	
+
 	public function testDeleteForbidden() {
 		$this->expectException(\Sabre\DAV\Exception\Forbidden::class);
 
@@ -150,7 +150,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->assertSame($this->node->getName(), $id);
 	}
 
-	
+
 	public function testSetName() {
 		$this->expectException(\Sabre\DAV\Exception\MethodNotAllowed::class);
 
@@ -195,7 +195,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->assertTrue($this->node->updateComment($msg));
 	}
 
-	
+
 	public function testUpdateCommentLogException() {
 		$this->expectException(\Exception::class);
 		$this->expectExceptionMessage('buh!');
@@ -236,7 +236,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->node->updateComment($msg);
 	}
 
-	
+
 	public function testUpdateCommentMessageTooLongException() {
 		$this->expectException(\Sabre\DAV\Exception\BadRequest::class);
 		$this->expectExceptionMessage('Message exceeds allowed character limit of');
@@ -275,7 +275,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->node->updateComment('foo');
 	}
 
-	
+
 	public function testUpdateForbiddenByUser() {
 		$this->expectException(\Sabre\DAV\Exception\Forbidden::class);
 
@@ -310,7 +310,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->node->updateComment($msg);
 	}
 
-	
+
 	public function testUpdateForbiddenByType() {
 		$this->expectException(\Sabre\DAV\Exception\Forbidden::class);
 
@@ -340,7 +340,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$this->node->updateComment($msg);
 	}
 
-	
+
 	public function testUpdateForbiddenByNotLoggedIn() {
 		$this->expectException(\Sabre\DAV\Exception\Forbidden::class);
 
@@ -403,6 +403,7 @@ class CommentsNodeTest extends \Test\TestCase {
 			$ns . 'latestChildDateTime' => new \DateTime('2016-01-12 18:48:00'),
 			$ns . 'objectType' => 'files',
 			$ns . 'objectId' => '1848',
+			$ns . 'referenceId' => 'ref',
 			$ns . 'isUnread' => null,
 		];
 
@@ -469,6 +470,10 @@ class CommentsNodeTest extends \Test\TestCase {
 			->method('getObjectId')
 			->willReturn($expected[$ns . 'objectId']);
 
+		$this->comment->expects($this->once())
+			->method('getReferenceId')
+			->willReturn($expected[$ns . 'referenceId']);
+
 		$user = $this->getMockBuilder(IUser::class)
 			->disableOriginalConstructor()
 			->getMock();
@@ -484,7 +489,7 @@ class CommentsNodeTest extends \Test\TestCase {
 		$properties = $this->node->getProperties(null);
 
 		foreach($properties as $name => $value) {
-			$this->assertTrue(array_key_exists($name, $expected));
+			$this->assertArrayHasKey($name, $expected);
 			$this->assertSame($expected[$name], $value);
 			unset($expected[$name]);
 		}

apps/settings/lib/Controller/CheckSetupController.php

@@ -46,6 +46,7 @@ use GuzzleHttp\Exception\ClientException;
 use OC;
 use OC\AppFramework\Http;
 use OC\DB\Connection;
+use OC\DB\MissingColumnInformation;
 use OC\DB\MissingIndexInformation;
 use OC\DB\SchemaWrapper;
 use OC\IntegrityCheck\Checker;
@@ -445,6 +446,15 @@ Raw output
 		return $indexInfo->getListOfMissingIndexes();
 	}
 
+	protected function hasMissingColumns(): array {
+		$indexInfo = new MissingColumnInformation();
+		// Dispatch event so apps can also hint for pending index updates if needed
+		$event = new GenericEvent($indexInfo);
+		$this->dispatcher->dispatch(IDBConnection::CHECK_MISSING_COLUMNS_EVENT, $event);
+
+		return $indexInfo->getListOfMissingColumns();
+	}
+
 	protected function isSqliteUsed() {
 		return strpos($this->config->getSystemValue('dbtype'), 'sqlite') !== false;
 	}
@@ -693,6 +703,7 @@ Raw output
 				'isSettimelimitAvailable' => $this->isSettimelimitAvailable(),
 				'hasFreeTypeSupport' => $this->hasFreeTypeSupport(),
 				'missingIndexes' => $this->hasMissingIndexes(),
+				'missingColumns' => $this->hasMissingColumns(),
 				'isSqliteUsed' => $this->isSqliteUsed(),
 				'databaseConversionDocumentation' => $this->urlGenerator->linkToDocs('admin-db-conversion'),
 				'isPHPMailerUsed' => $this->isPHPMailerUsed(),

apps/settings/tests/Controller/CheckSetupControllerTest.php

@@ -583,6 +583,7 @@ class CheckSetupControllerTest extends TestCase {
 				'isSqliteUsed' => false,
 				'databaseConversionDocumentation' => 'http://docs.example.org/server/go.php?to=admin-db-conversion',
 				'missingIndexes' => [],
+				'missingColumns' => [],
 				'isPHPMailerUsed' => false,
 				'mailSettingsDocumentation' => 'https://server/index.php/settings/admin',
 				'isMemoryLimitSufficient' => true,

core/Application.php

@@ -39,6 +39,7 @@ use OC\Authentication\Listeners\RemoteWipeNotificationsListener;
 use OC\Authentication\Listeners\UserDeletedStoreCleanupListener;
 use OC\Authentication\Notifications\Notifier as AuthenticationNotifier;
 use OC\Core\Notification\RemoveLinkSharesNotifier;
+use OC\DB\MissingColumnInformation;
 use OC\DB\MissingIndexInformation;
 use OC\DB\SchemaWrapper;
 use OCP\AppFramework\App;
@@ -167,6 +168,23 @@ class Application extends App {
 			}
 		);
 
+		$eventDispatcher->addListener(IDBConnection::CHECK_MISSING_COLUMNS_EVENT,
+			function (GenericEvent $event) use ($container) {
+				/** @var MissingColumnInformation $subject */
+				$subject = $event->getSubject();
+
+				$schema = new SchemaWrapper($container->query(IDBConnection::class));
+
+				if ($schema->hasTable('comments')) {
+					$table = $schema->getTable('comments');
+
+					if (!$table->hasColumn('reference_id')) {
+						$subject->addHintForMissingColumn($table->getName(), 'reference_id');
+					}
+				}
+			}
+		);
+
 		$eventDispatcher->addServiceListener(RemoteWipeStarted::class, RemoteWipeActivityListener::class);
 		$eventDispatcher->addServiceListener(RemoteWipeStarted::class, RemoteWipeNotificationsListener::class);
 		$eventDispatcher->addServiceListener(RemoteWipeStarted::class, RemoteWipeEmailListener::class);

core/Command/Db/AddMissingColumns.php

@@ -0,0 +1,105 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2020 Joas Schilling <coding@schilljs.com>
+ *
+ * @author Joas Schilling <coding@schilljs.com>
+ *
+ * @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 OC\Core\Command\Db;
+
+use OC\DB\SchemaWrapper;
+use OCP\IDBConnection;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Component\EventDispatcher\GenericEvent;
+
+/**
+ * Class AddMissingColumns
+ *
+ * if you added a new lazy column to the database, this is the right place to add
+ * your update routine for existing instances
+ *
+ * @package OC\Core\Command\Db
+ */
+class AddMissingColumns extends Command {
+
+	/** @var IDBConnection */
+	private $connection;
+
+	/** @var EventDispatcherInterface */
+	private $dispatcher;
+
+	public function __construct(IDBConnection $connection, EventDispatcherInterface $dispatcher) {
+		parent::__construct();
+
+		$this->connection = $connection;
+		$this->dispatcher = $dispatcher;
+	}
+
+	protected function configure() {
+		$this
+			->setName('db:add-missing-columns')
+			->setDescription('Add missing optional columns to the database tables');
+	}
+
+	protected function execute(InputInterface $input, OutputInterface $output) {
+		$this->addCoreColumns($output);
+
+		// Dispatch event so apps can also update columns if needed
+		$event = new GenericEvent($output);
+		$this->dispatcher->dispatch(IDBConnection::ADD_MISSING_COLUMNS_EVENT, $event);
+	}
+
+	/**
+	 * add missing indices to the share table
+	 *
+	 * @param OutputInterface $output
+	 * @throws \Doctrine\DBAL\Schema\SchemaException
+	 */
+	private function addCoreColumns(OutputInterface $output) {
+
+		$output->writeln('<info>Check columns of the comments table.</info>');
+
+		$schema = new SchemaWrapper($this->connection);
+		$updated = false;
+
+		if ($schema->hasTable('comments')) {
+			$table = $schema->getTable('comments');
+			if (!$table->hasColumn('reference_id')) {
+				$output->writeln('<info>Adding additional reference_id column to the comments table, this can take some time...</info>');
+				$table->addColumn('reference_id', 'string', [
+					'notnull' => false,
+					'length' => 64,
+				]);
+				$this->connection->migrateToSchema($schema->getWrappedSchema());
+				$updated = true;
+				$output->writeln('<info>Comments table updated successfully.</info>');
+			}
+		}
+
+		if (!$updated) {
+			$output->writeln('<info>Done.</info>');
+		}
+	}
+}

core/Command/Db/AddMissingIndices.php

@@ -43,7 +43,7 @@ use Symfony\Component\EventDispatcher\GenericEvent;
  * Class AddMissingIndices
  *
  * if you added any new indices to the database, this is the right place to add
- * it your update routine for existing instances
+ * your update routine for existing instances
  *
  * @package OC\Core\Command\Db
  */

core/Migrations/Version13000Date20170718121200.php

@@ -769,6 +769,10 @@ class Version13000Date20170718121200 extends SimpleMigrationStep {
 				'length' => 64,
 				'default' => '',
 			]);
+			$table->addColumn('reference_id', 'string', [
+				'notnull' => false,
+				'length' => 64,
+			]);
 			$table->setPrimaryKey(['id']);
 			$table->addIndex(['parent_id'], 'comments_parent_id_index');
 			$table->addIndex(['topmost_parent_id'], 'comments_topmost_parent_id_idx');

core/js/setupchecks.js

@@ -357,6 +357,21 @@
 							type: OC.SetupChecks.MESSAGE_TYPE_INFO
 						})
 					}
+					if (data.missingColumns.length > 0) {
+						var listOfMissingColumns = "";
+						data.missingColumns.forEach(function(element){
+							listOfMissingColumns += "<li>";
+							listOfMissingColumns += t('core', 'Missing optional column "{columnName}" in table "{tableName}".', element);
+							listOfMissingColumns += "</li>";
+						});
+						messages.push({
+							msg: t(
+								'core',
+								'The database is missing some optional columns. Due to the fact that adding columns on big tables could take some time they were not added automatically when they can be optional. By running "occ db:add-missing-columns" those missing columns could be added manually while the instance keeps running. Once the columns are added some features might improve responsiveness or usability.'
+							) + "<ul>" + listOfMissingColumns + "</ul>",
+							type: OC.SetupChecks.MESSAGE_TYPE_INFO
+						})
+					}
 					if (data.recommendedPHPModules.length > 0) {
 						var listOfRecommendedPHPModules = "";
 						data.recommendedPHPModules.forEach(function(element){

core/js/tests/specs/setupchecksSpec.js

@@ -240,6 +240,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -293,6 +294,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -347,6 +349,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -399,6 +402,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -449,6 +453,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -499,6 +504,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -551,6 +557,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -601,6 +608,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: false,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -651,6 +659,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -722,6 +731,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -773,6 +783,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -824,6 +835,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -875,6 +887,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: false,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -925,6 +938,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -975,6 +989,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0
@@ -1026,6 +1041,7 @@ describe('OC.SetupChecks tests', function() {
 					isSettimelimitAvailable: true,
 					hasFreeTypeSupport: true,
 					missingIndexes: [],
+					missingColumns: [],
 					cronErrors: [],
 					cronInfo: {
 						diffInSeconds: 0

core/register_command.php

@@ -99,6 +99,7 @@ if (\OC::$server->getConfig()->getSystemValue('installed', false)) {
 	$application->add(new OC\Core\Command\Db\ConvertMysqlToMB4(\OC::$server->getConfig(), \OC::$server->getDatabaseConnection(), \OC::$server->getURLGenerator(), \OC::$server->getLogger()));
 	$application->add(new OC\Core\Command\Db\ConvertFilecacheBigInt(\OC::$server->getDatabaseConnection()));
 	$application->add(new OC\Core\Command\Db\AddMissingIndices(\OC::$server->getDatabaseConnection(), \OC::$server->getEventDispatcher()));
+	$application->add(new OC\Core\Command\Db\AddMissingColumns(\OC::$server->getDatabaseConnection(), \OC::$server->getEventDispatcher()));
 	$application->add(new OC\Core\Command\Db\Migrations\StatusCommand(\OC::$server->getDatabaseConnection()));
 	$application->add(new OC\Core\Command\Db\Migrations\MigrateCommand(\OC::$server->getDatabaseConnection()));
 	$application->add(new OC\Core\Command\Db\Migrations\GenerateCommand(\OC::$server->getDatabaseConnection(), \OC::$server->getAppManager()));

lib/composer/composer/autoload_classmap.php

@@ -738,6 +738,7 @@ return array(
     'OC\\Core\\Command\\Config\\System\\DeleteConfig' => $baseDir . '/core/Command/Config/System/DeleteConfig.php',
     'OC\\Core\\Command\\Config\\System\\GetConfig' => $baseDir . '/core/Command/Config/System/GetConfig.php',
     'OC\\Core\\Command\\Config\\System\\SetConfig' => $baseDir . '/core/Command/Config/System/SetConfig.php',
+    'OC\\Core\\Command\\Db\\AddMissingColumns' => $baseDir . '/core/Command/Db/AddMissingColumns.php',
     'OC\\Core\\Command\\Db\\AddMissingIndices' => $baseDir . '/core/Command/Db/AddMissingIndices.php',
     'OC\\Core\\Command\\Db\\ConvertFilecacheBigInt' => $baseDir . '/core/Command/Db/ConvertFilecacheBigInt.php',
     'OC\\Core\\Command\\Db\\ConvertMysqlToMB4' => $baseDir . '/core/Command/Db/ConvertMysqlToMB4.php',
@@ -873,6 +874,7 @@ return array(
     'OC\\DB\\MigrationException' => $baseDir . '/lib/private/DB/MigrationException.php',
     'OC\\DB\\MigrationService' => $baseDir . '/lib/private/DB/MigrationService.php',
     'OC\\DB\\Migrator' => $baseDir . '/lib/private/DB/Migrator.php',
+    'OC\\DB\\MissingColumnInformation' => $baseDir . '/lib/private/DB/MissingColumnInformation.php',
     'OC\\DB\\MissingIndexInformation' => $baseDir . '/lib/private/DB/MissingIndexInformation.php',
     'OC\\DB\\MySQLMigrator' => $baseDir . '/lib/private/DB/MySQLMigrator.php',
     'OC\\DB\\MySqlTools' => $baseDir . '/lib/private/DB/MySqlTools.php',

lib/composer/composer/autoload_static.php

@@ -767,6 +767,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OC\\Core\\Command\\Config\\System\\DeleteConfig' => __DIR__ . '/../../..' . '/core/Command/Config/System/DeleteConfig.php',
         'OC\\Core\\Command\\Config\\System\\GetConfig' => __DIR__ . '/../../..' . '/core/Command/Config/System/GetConfig.php',
         'OC\\Core\\Command\\Config\\System\\SetConfig' => __DIR__ . '/../../..' . '/core/Command/Config/System/SetConfig.php',
+        'OC\\Core\\Command\\Db\\AddMissingColumns' => __DIR__ . '/../../..' . '/core/Command/Db/AddMissingColumns.php',
         'OC\\Core\\Command\\Db\\AddMissingIndices' => __DIR__ . '/../../..' . '/core/Command/Db/AddMissingIndices.php',
         'OC\\Core\\Command\\Db\\ConvertFilecacheBigInt' => __DIR__ . '/../../..' . '/core/Command/Db/ConvertFilecacheBigInt.php',
         'OC\\Core\\Command\\Db\\ConvertMysqlToMB4' => __DIR__ . '/../../..' . '/core/Command/Db/ConvertMysqlToMB4.php',
@@ -902,6 +903,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OC\\DB\\MigrationException' => __DIR__ . '/../../..' . '/lib/private/DB/MigrationException.php',
         'OC\\DB\\MigrationService' => __DIR__ . '/../../..' . '/lib/private/DB/MigrationService.php',
         'OC\\DB\\Migrator' => __DIR__ . '/../../..' . '/lib/private/DB/Migrator.php',
+        'OC\\DB\\MissingColumnInformation' => __DIR__ . '/../../..' . '/lib/private/DB/MissingColumnInformation.php',
         'OC\\DB\\MissingIndexInformation' => __DIR__ . '/../../..' . '/lib/private/DB/MissingIndexInformation.php',
         'OC\\DB\\MySQLMigrator' => __DIR__ . '/../../..' . '/lib/private/DB/MySQLMigrator.php',
         'OC\\DB\\MySqlTools' => __DIR__ . '/../../..' . '/lib/private/DB/MySqlTools.php',

lib/private/Comments/Comment.php

@@ -42,6 +42,7 @@ class Comment implements IComment {
 		'actorId'         => '',
 		'objectType'      => '',
 		'objectId'        => '',
+		'referenceId'     => null,
 		'creationDT'      => null,
 		'latestChildDT'   => null,
 	];
@@ -395,6 +396,36 @@ class Comment implements IComment {
 		return $this;
 	}
 
+	/**
+	 * returns the reference id of the comment
+	 *
+	 * @return string|null
+	 * @since 19.0.0
+	 */
+	public function getReferenceId(): ?string {
+		return $this->data['referenceId'];
+	}
+
+	/**
+	 * sets (overwrites) the reference id of the comment
+	 *
+	 * @param string $referenceId e.g. sha256 hash sum
+	 * @return IComment
+	 * @since 19.0.0
+	 */
+	public function setReferenceId(?string $referenceId): IComment {
+		if ($referenceId === null) {
+			$this->data['referenceId'] = $referenceId;
+		} else {
+			$referenceId = trim($referenceId);
+			if ($referenceId === '') {
+				throw new \InvalidArgumentException('Non empty string expected.');
+			}
+			$this->data['referenceId'] = $referenceId;
+		}
+		return $this;
+	}
+
 	/**
 	 * sets the comment data based on an array with keys as taken from the
 	 * database.

lib/private/Comments/Manager.php

@@ -29,6 +29,7 @@
 namespace OC\Comments;
 
 use Doctrine\DBAL\Exception\DriverException;
+use Doctrine\DBAL\Exception\InvalidFieldNameException;
 use OCP\Comments\CommentsEvent;
 use OCP\Comments\IComment;
 use OCP\Comments\ICommentsEventHandler;
@@ -96,6 +97,7 @@ class Manager implements ICommentsManager {
 			$data['latest_child_timestamp'] = new \DateTime($data['latest_child_timestamp']);
 		}
 		$data['children_count'] = (int)$data['children_count'];
+		$data['reference_id'] = $data['reference_id'] ?? null;
 		return $data;
 	}
 
@@ -744,23 +746,46 @@ class Manager implements ICommentsManager {
 	 * @param IComment $comment
 	 * @return bool
 	 */
-	protected function insert(IComment &$comment) {
+	protected function insert(IComment $comment): bool {
+
+		try {
+			$result = $this->insertQuery($comment, true);
+		} catch (InvalidFieldNameException $e) {
+			// The reference id field was only added in Nextcloud 19.
+			// In order to not cause too long waiting times on the update,
+			// it was decided to only add it lazy, as it is also not a critical
+			// feature, but only helps to have a better experience while commenting.
+			// So in case the reference_id field is missing,
+			// we simply save the comment without that field.
+			$result = $this->insertQuery($comment, false);
+		}
+
+		return $result;
+	}
+
+	protected function insertQuery(IComment $comment, bool $tryWritingReferenceId): bool {
 		$qb = $this->dbConn->getQueryBuilder();
-		$affectedRows = $qb
-			->insert('comments')
-			->values([
-				'parent_id' => $qb->createNamedParameter($comment->getParentId()),
-				'topmost_parent_id' => $qb->createNamedParameter($comment->getTopmostParentId()),
-				'children_count' => $qb->createNamedParameter($comment->getChildrenCount()),
-				'actor_type' => $qb->createNamedParameter($comment->getActorType()),
-				'actor_id' => $qb->createNamedParameter($comment->getActorId()),
-				'message' => $qb->createNamedParameter($comment->getMessage()),
-				'verb' => $qb->createNamedParameter($comment->getVerb()),
-				'creation_timestamp' => $qb->createNamedParameter($comment->getCreationDateTime(), 'datetime'),
-				'latest_child_timestamp' => $qb->createNamedParameter($comment->getLatestChildDateTime(), 'datetime'),
-				'object_type' => $qb->createNamedParameter($comment->getObjectType()),
-				'object_id' => $qb->createNamedParameter($comment->getObjectId()),
-			])
+
+		$values = [
+			'parent_id' => $qb->createNamedParameter($comment->getParentId()),
+			'topmost_parent_id' => $qb->createNamedParameter($comment->getTopmostParentId()),
+			'children_count' => $qb->createNamedParameter($comment->getChildrenCount()),
+			'actor_type' => $qb->createNamedParameter($comment->getActorType()),
+			'actor_id' => $qb->createNamedParameter($comment->getActorId()),
+			'message' => $qb->createNamedParameter($comment->getMessage()),
+			'verb' => $qb->createNamedParameter($comment->getVerb()),
+			'creation_timestamp' => $qb->createNamedParameter($comment->getCreationDateTime(), 'datetime'),
+			'latest_child_timestamp' => $qb->createNamedParameter($comment->getLatestChildDateTime(), 'datetime'),
+			'object_type' => $qb->createNamedParameter($comment->getObjectType()),
+			'object_id' => $qb->createNamedParameter($comment->getObjectId()),
+		];
+
+		if ($tryWritingReferenceId) {
+			$values['reference_id'] = $qb->createNamedParameter($comment->getReferenceId());
+		}
+
+		$affectedRows = $qb->insert('comments')
+			->values($values)
 			->execute();
 
 		if ($affectedRows > 0) {
@@ -785,8 +810,21 @@ class Manager implements ICommentsManager {
 		$this->sendEvent(CommentsEvent::EVENT_PRE_UPDATE, $this->get($comment->getId()));
 		$this->uncache($comment->getId());
 
+		try {
+			$result = $this->updateQuery($comment, true);
+		} catch (InvalidFieldNameException $e) {
+			// See function insert() for explanation
+			$result = $this->updateQuery($comment, false);
+		}
+
+		$this->sendEvent(CommentsEvent::EVENT_UPDATE, $comment);
+
+		return $result;
+	}
+
+	protected function updateQuery(IComment $comment, bool $tryWritingReferenceId): bool {
 		$qb = $this->dbConn->getQueryBuilder();
-		$affectedRows = $qb
+		$qb
 			->update('comments')
 			->set('parent_id', $qb->createNamedParameter($comment->getParentId()))
 			->set('topmost_parent_id', $qb->createNamedParameter($comment->getTopmostParentId()))
@@ -798,17 +836,19 @@ class Manager implements ICommentsManager {
 			->set('creation_timestamp', $qb->createNamedParameter($comment->getCreationDateTime(), 'datetime'))
 			->set('latest_child_timestamp', $qb->createNamedParameter($comment->getLatestChildDateTime(), 'datetime'))
 			->set('object_type', $qb->createNamedParameter($comment->getObjectType()))
-			->set('object_id', $qb->createNamedParameter($comment->getObjectId()))
-			->where($qb->expr()->eq('id', $qb->createParameter('id')))
-			->setParameter('id', $comment->getId())
+			->set('object_id', $qb->createNamedParameter($comment->getObjectId()));
+
+		if ($tryWritingReferenceId) {
+			$qb->set('reference_id', $qb->createNamedParameter($comment->getReferenceId()));
+		}
+
+		$affectedRows = $qb->where($qb->expr()->eq('id', $qb->createNamedParameter($comment->getId())))
 			->execute();
 
 		if ($affectedRows === 0) {
 			throw new NotFoundException('Comment to update does ceased to exist');
 		}
 
-		$this->sendEvent(CommentsEvent::EVENT_UPDATE, $comment);
-
 		return $affectedRows > 0;
 	}
 

lib/private/DB/MissingColumnInformation.php

@@ -0,0 +1,43 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2020 Joas Schilling <coding@schilljs.com>
+ *
+ * @author Joas Schilling <coding@schilljs.com>
+ *
+ * @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 OC\DB;
+
+class MissingColumnInformation {
+
+	private $listOfMissingColumns = [];
+
+	public function addHintForMissingColumn(string $tableName, string $columnName): void {
+		$this->listOfMissingColumns[] = [
+			'tableName' => $tableName,
+			'columnName' => $columnName,
+		];
+	}
+
+	public function getListOfMissingColumns(): array {
+		return $this->listOfMissingColumns;
+	}
+}

lib/public/Comments/IComment.php

@@ -263,4 +263,21 @@ interface IComment {
 	 */
 	public function setObject($objectType, $objectId);
 
+	/**
+	 * returns the reference id of the comment
+	 *
+	 * @return string|null
+	 * @since 19.0.0
+	 */
+	public function getReferenceId(): ?string;
+
+	/**
+	 * sets (overwrites) the reference id of the comment
+	 *
+	 * @param string|null $referenceId e.g. sha256 hash sum
+	 * @return IComment
+	 * @since 19.0.0
+	 */
+	public function setReferenceId(?string $referenceId): IComment;
+
 }

lib/public/IDBConnection.php

@@ -51,6 +51,8 @@ interface IDBConnection {
 
 	const ADD_MISSING_INDEXES_EVENT = self::class . '::ADD_MISSING_INDEXES';
 	const CHECK_MISSING_INDEXES_EVENT = self::class . '::CHECK_MISSING_INDEXES';
+	const ADD_MISSING_COLUMNS_EVENT = self::class . '::ADD_MISSING_COLUMNS';
+	const CHECK_MISSING_COLUMNS_EVENT = self::class . '::CHECK_MISSING_COLUMNS';
 
 	/**
 	 * Gets the QueryBuilder for the connection.