Put the dompdf fonts and temp files in a folder inside var/dompdf, which should always be writable by the server process

src/Services/LabelSystem/DompdfFactory.php

@@ -0,0 +1,54 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2023 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 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 App\Services\LabelSystem;
+
+use Dompdf\Dompdf;
+use Jbtronics\DompdfFontLoaderBundle\Services\DompdfFactoryInterface;
+use Symfony\Component\DependencyInjection\Attribute\AsDecorator;
+
+#[AsDecorator(decorates: DompdfFactoryInterface::class)]
+class DompdfFactory implements DompdfFactoryInterface
+{
+    public function __construct(private string $fontDirectory, private string $tmpDirectory)
+    {
+        //Create folder if it does not exist
+        $this->createDirectoryIfNotExisting($this->fontDirectory);
+        $this->createDirectoryIfNotExisting($this->tmpDirectory);
+    }
+
+    private function createDirectoryIfNotExisting(string $path): void
+    {
+        if (!is_dir($path)) {
+            if (!mkdir($concurrentDirectory = $path, 0777, true) && !is_dir($concurrentDirectory)) {
+                throw new \RuntimeException(sprintf('Directory "%s" was not created', $concurrentDirectory));
+            }
+        }
+    }
+
+    public function create(): Dompdf
+    {
+        return new Dompdf([
+            'fontDir' => $this->fontDirectory,
+            'fontCache' => $this->fontDirectory,
+            'tempDir' => $this->tmpDirectory,
+        ]);
+    }
+}