Introduce ISetConfigValuesTransactional for transactional config behaviour

src/Core/Config/Capability/ISetConfigValuesTransactional.php

@@ -0,0 +1,84 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2023, the Friendica project
+ *
+ * @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 <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Core\Config\Capability;
+
+use Friendica\Core\Config\Exception\ConfigPersistenceException;
+
+/**
+ * Interface for transactional saving of config values
+ * It buffers every set/delete until "save()" is called
+ */
+interface ISetConfigValuesTransactional
+{
+	/**
+	 * Get a particular user's config variable given the category name
+	 * ($cat) and a $key.
+	 *
+	 * Get a particular config value from the given category ($cat)
+	 *
+	 * @param string  $cat        The category of the configuration value
+	 * @param string  $key           The configuration key to query
+	 *
+	 * @return mixed Stored value or null if it does not exist
+	 *
+	 * @throws ConfigPersistenceException In case the persistence layer throws errors
+	 *
+	 */
+	public function get(string $cat, string $key);
+
+	/**
+	 * Sets a configuration value for system config
+	 *
+	 * Stores a config value ($value) in the category ($cat) under the key ($key)
+	 *
+	 * Note: Please do not store booleans - convert to 0/1 integer values!
+	 *
+	 * @param string $cat The category of the configuration value
+	 * @param string $key    The configuration key to set
+	 * @param mixed  $value  The value to store
+	 *
+	 * @return static the current instance
+	 *
+	 * @throws ConfigPersistenceException In case the persistence layer throws errors
+	 */
+	public function set(string $cat, string $key, $value): self;
+
+	/**
+	 * Deletes the given key from the system configuration.
+	 *
+	 * @param string $cat The category of the configuration value
+	 * @param string $key The configuration key to delete
+	 *
+	 * @return static the current instance
+	 *
+	 * @throws ConfigPersistenceException In case the persistence layer throws errors
+	 *
+	 */
+	public function delete(string $cat, string $key): self;
+
+	/**
+	 * Saves the node specific config values
+	 *
+	 * @throws ConfigPersistenceException In case the persistence layer throws errors
+	 */
+	public function save(): void;
+}