Add exception when message is empty in FormatteNavNotification::createFromNotification

- Filter out message less notifications in Ping

src/Navigation/Notifications/Exception/NoMessageException.php

@@ -0,0 +1,26 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2022, 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\Navigation\Notifications\Exception;
+
+class NoMessageException extends \Exception
+{
+}

src/Navigation/Notifications/Factory/FormattedNavNotification.php

@@ -25,6 +25,7 @@ use Friendica\BaseFactory;
 use Friendica\Core\Renderer;
 use Friendica\Model\Contact;
 use Friendica\Navigation\Notifications\Entity;
+use Friendica\Navigation\Notifications\Exception\NoMessageException;
 use Friendica\Navigation\Notifications\ValueObject;
 use Friendica\Util\DateTimeFormat;
 use Friendica\Util\Proxy;
@@ -94,10 +95,22 @@ class FormattedNavNotification extends BaseFactory
 		);
 	}
 
+	/**
+	 * @param Entity\Notification $notification
+	 * @return ValueObject\FormattedNavNotification
+	 * @throws NoMessageException
+	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
+	 * @throws \Friendica\Network\HTTPException\NotFoundException
+	 * @throws \Friendica\Network\HTTPException\ServiceUnavailableException
+	 */
 	public function createFromNotification(Entity\Notification $notification): ValueObject\FormattedNavNotification
 	{
 		$message = $this->notification->getMessageFromNotification($notification);
 
+		if (empty($message)) {
+			throw new NoMessageException();
+		}
+
 		if (!isset(self::$contacts[$notification->actorId])) {
 			self::$contacts[$notification->actorId] = Contact::getById($notification->actorId, ['name', 'url']);
 		}

src/Navigation/Notifications/ValueObject/FormattedNavNotification.php

@@ -21,12 +21,12 @@
 
 namespace Friendica\Navigation\Notifications\ValueObject;
 
-use Friendica\BaseDataTransferObject;
+use Friendica\BaseEntity;
 
 /**
  * A view-only object for printing item notifications to the frontend
  */
-class FormattedNavNotification extends BaseDataTransferObject
+class FormattedNavNotification extends BaseEntity
 {
 	/** @var array */
 	protected $contact;