Merge pull request #25091 from nextcloud/enhancement/ocp-db-exception-abstraction

Add our own DB exception abstraction

2 files changed, 151 insertions, 0 deletions

diff --git a/lib/public/DB/Exception.php b/lib/public/DB/Exception.php
new file mode 100644
index 00000000000..1154530e85d
--- /dev/null
+++ b/lib/public/DB/Exception.php
@@ -0,0 +1,149 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * @copyright 2021 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2021 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @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\DB;
+
+use Exception as BaseException;
+
+/**
+ * Database exception
+ *
+ * Thrown by Nextcloud's database abstraction layer. This is the base class that
+ * any specific exception will extend. Use this class in your try-catch to catch
+ * *any* error related to the database. Use any of the subclasses in the same
+ * namespace if you are only interested in specific errors.
+ *
+ * @psalm-immutable
+ * @since 21.0.0
+ */
+class Exception extends BaseException {
+
+	/**
+	 * Nextcloud lost connection to the database
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_CONNECTION_LOST = 1;
+
+	/**
+	 * A database constraint was violated
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_CONSTRAINT_VIOLATION = 2;
+
+	/**
+	 * A database object (table, column, index) already exists
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_DATABASE_OBJECT_EXISTS = 3;
+
+	/**
+	 * A database object (table, column, index) can't be found
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_DATABASE_OBJECT_NOT_FOUND = 4;
+
+	/**
+	 * The database ran into a deadlock
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_DEADLOCK = 5;
+
+	/**
+	 * The database driver encountered an issue
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_DRIVER = 6;
+
+	/**
+	 * A foreign key constraint was violated
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_FOREIGN_KEY_VIOLATION = 7;
+
+	/**
+	 * An invalid argument was passed to the database abstraction
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_INVALID_ARGUMENT = 8;
+
+	/**
+	 * A field name was invalid
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_INVALID_FIELD_NAME = 9;
+
+	/**
+	 * A name in the query was ambiguous
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_NON_UNIQUE_FIELD_NAME = 10;
+
+	/**
+	 * A not null contraint was violated
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_NOT_NULL_CONSTRAINT_VIOLATION = 11;
+
+	/**
+	 * A generic server error was encountered
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_SERVER = 12;
+
+	/**
+	 * A syntax error was reported by the server
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_SYNTAX_ERROR = 13;
+
+	/**
+	 * A unique constraint was violated
+	 *
+	 * @since 21.0.0
+	 */
+	public const REASON_UNIQUE_CONSTRAINT_VIOLATION = 14;
+
+	/**
+	 * @return int|null
+	 * @psalm-return Exception::REASON_*
+	 * @since 21.0.0
+	 */
+	public function getReason(): ?int {
+		return null;
+	}
+}
diff --git a/lib/public/DB/QueryBuilder/IQueryBuilder.php b/lib/public/DB/QueryBuilder/IQueryBuilder.php
index 8fcbd6c3276..24de7b4ce60 100644
--- a/lib/public/DB/QueryBuilder/IQueryBuilder.php
+++ b/lib/public/DB/QueryBuilder/IQueryBuilder.php
@@ -29,6 +29,7 @@
 namespace OCP\DB\QueryBuilder;
 
 use Doctrine\DBAL\Connection;
+use OCP\DB\Exception;
 use OCP\DB\IResult;
 
 /**
@@ -154,6 +155,7 @@ interface IQueryBuilder {
 	 *          to bridge old code to the new API
 	 *
 	 * @return IResult|int
+	 * @throws Exception since 21.0.0
 	 * @since 8.2.0
 	 */
 	public function execute();