Replace BaseEntity with BaseDataTransferObject class for API representation classes

src/BaseDataTransferObject.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * @copyright Copyright (C) 2020, Friendica
+ *
+ * @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;
+
+/**
+ * These data transfer object classes are meant for API representations. As such, their members should be protected.
+ * Then the JsonSerializable interface ensures the protected members will be included in a JSON encode situation.
+ *
+ * Constructors are supposed to take as arguments the Friendica dependencies/model/collection/data it needs to
+ * populate the class members.
+ */
+abstract class BaseDataTransferObject implements \JsonSerializable
+{
+	/**
+	 * Returns the current entity as an json array
+	 *
+	 * @return array
+	 */
+	public function jsonSerialize(): array
+	{
+		return $this->toArray();
+	}
+
+	/**
+	 * Returns the current entity as an array
+	 *
+	 * @return array
+	 */
+	public function toArray(): array
+	{
+		return get_object_vars($this);
+	}
+}