Allow to specifiy a path to a builtin ressource via the url field.

src/Validator/Constraints/UrlOrBuiltin.php

@@ -0,0 +1,46 @@
+<?php
+/**
+ *
+ * part-db version 0.1
+ * Copyright (C) 2005 Christoph Lechner
+ * http://www.cl-projects.de/
+ *
+ * part-db version 0.2+
+ * Copyright (C) 2009 K. Jacobs and others (see authors.php)
+ * http://code.google.com/p/part-db/
+ *
+ * Part-DB Version 0.4+
+ * Copyright (C) 2016 - 2019 Jan Böhmer
+ * https://github.com/jbtronics
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ *
+ */
+
+namespace App\Validator\Constraints;
+
+
+use App\Entity\Attachments\Attachment;
+use Symfony\Component\Validator\Constraints\Url;
+
+/**
+ * Constraints the field that way that the content is either a url or a path to a builtin ressource (like %FOOTPRINTS%)
+ * @package App\Validator\Constraints
+ */
+class UrlOrBuiltin extends Url
+{
+    /** @var array A list of the placeholders that are treated as builtin */
+    public $allowed_placeholders = Attachment::BUILTIN_PLACEHOLDER;
+}