Ensure string column limit of 4.000 characters

apps/files_external/appinfo/info.xml

@@ -9,7 +9,7 @@ This application enables administrators to configure connections to external sto
 
 External storage can be configured using the GUI or at the command line. This second option provides the advanced user with more flexibility for configuring bulk external storage mounts and setting mount priorities. More information is available in the external storage GUI documentation and the external storage Configuration File documentation.
 	</description>
-	<version>1.16.0</version>
+	<version>1.16.1</version>
 	<licence>agpl</licence>
 	<author>Robin Appelman</author>
 	<author>Michael Gapczynski</author>

apps/files_external/lib/Migration/Version1011Date20200630192246.php

@@ -116,7 +116,7 @@ public function changeSchema(IOutput $output, Closure $schemaClosure, array $opt
 			]);
 			$table->addColumn('value', Types::STRING, [
 				'notnull' => false,
-				'length' => 4096,
+				'length' => 4000,
 			]);
 			$table->setPrimaryKey(['config_id']);
 			$table->addUniqueIndex(['mount_id', 'key'], 'config_mount_key');

apps/files_external/lib/Migration/Version1016Date20220324154536.php

@@ -0,0 +1,54 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2022 Joas Schilling <[email protected]>
+ *
+ * @author Joas Schilling <[email protected]>
+ *
+ * @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\Files_External\Migration;
+
+use Closure;
+use OCP\DB\ISchemaWrapper;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+
+class Version1016Date20220324154536 extends SimpleMigrationStep {
+
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 */
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options): ?ISchemaWrapper {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		$table = $schema->getTable('external_config');
+		$column = $table->getColumn('value');
+
+		if ($column->getLength() > 4000) {
+			$column->setLength(4000);
+			return $schema;
+		}
+
+		return null;
+	}
+}

lib/private/DB/MigrationService.php

@@ -594,6 +594,10 @@ public function ensureOracleConstraints(Schema $sourceSchema, Schema $targetSche
 				if ((!$sourceTable instanceof Table || !$sourceTable->hasColumn($thing->getName())) && $thing->getNotnull() && $thing->getType()->getName() === Types::BOOLEAN) {
 					throw new \InvalidArgumentException('Column "' . $table->getName() . '"."' . $thing->getName() . '" is type Bool and also NotNull, so it can not store "false".');
 				}
+
+				if ($thing->getLength() > 4000 && $thing->getType()->getName() === Types::STRING) {
+					throw new \InvalidArgumentException('Column "' . $table->getName() . '"."' . $thing->getName() . '" is type String, but exceeding the 4.000 length limit.');
+				}
 			}
 
 			foreach ($table->getIndexes() as $thing) {

tests/lib/DB/MigrationsTest.php

@@ -716,4 +716,44 @@ public function testEnsureOracleConstraintsBooleanNotNull() {
 
 		self::invokePrivate($this->migrationService, 'ensureOracleConstraints', [$sourceSchema, $schema, 3]);
 	}
+
+
+	public function testEnsureOracleConstraintsStringLength4000() {
+		$this->expectException(\InvalidArgumentException::class);
+
+		$column = $this->createMock(Column::class);
+		$column->expects($this->any())
+			->method('getName')
+			->willReturn('aaaa');
+		$column->expects($this->any())
+			->method('getType')
+			->willReturn(Type::getType('string'));
+		$column->expects($this->any())
+			->method('getLength')
+			->willReturn(4001);
+
+		$table = $this->createMock(Table::class);
+		$table->expects($this->any())
+			->method('getName')
+			->willReturn(\str_repeat('a', 30));
+
+		$table->expects($this->once())
+			->method('getColumns')
+			->willReturn([$column]);
+
+		$schema = $this->createMock(Schema::class);
+		$schema->expects($this->once())
+			->method('getTables')
+			->willReturn([$table]);
+
+		$sourceSchema = $this->createMock(Schema::class);
+		$sourceSchema->expects($this->any())
+			->method('getTable')
+			->willThrowException(new SchemaException());
+		$sourceSchema->expects($this->any())
+			->method('hasSequence')
+			->willReturn(false);
+
+		self::invokePrivate($this->migrationService, 'ensureOracleConstraints', [$sourceSchema, $schema, 3]);
+	}
 }