Show markdown on pages.

src/Services/MarkdownParser.php

@@ -0,0 +1,87 @@
+<?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\Services;
+
+
+use Symfony\Contracts\Cache\CacheInterface;
+use Symfony\Contracts\Cache\ItemInterface;
+
+/**
+ * This class allows you to convert markdown text to HTML.
+ * @package App\Services
+ */
+class MarkdownParser
+{
+    protected $cache;
+    /** @var \Parsedown */
+    protected $parsedown;
+
+    public function __construct(CacheInterface $cache)
+    {
+        $this->cache = $cache;
+        $this->initParsedown();
+    }
+
+    protected function initParsedown()
+    {
+        $this->parsedown = new \Parsedown();
+        $this->parsedown->setSafeMode(true);
+    }
+
+    /**
+     * Converts the given markdown text to HTML.
+     * The result is cached.
+     * @param string $markdown The markdown text that should be parsed to html.
+     * @param bool $inline_mode Only allow inline markdown codes like (*bold* or **italic**), not something like tables
+     * @return string The HTML version of the given text.
+     * @throws \Psr\Cache\InvalidArgumentException
+     */
+    public function parse(string $markdown, bool $inline_mode = false) : string
+    {
+        //Generate key
+        if ($inline_mode) {
+            $key = 'markdown_i_' . md5($markdown);
+        } else {
+            $key = 'markdown_' . md5($markdown);
+        }
+        return $this->cache->get($key, function (ItemInterface $item) use ($markdown, $inline_mode) {
+            //Expire text after 2 months
+            $item->expiresAfter(311040000);
+
+            if ($inline_mode) {
+                return $this->parsedown->line($markdown);
+            }
+
+            return '<div class="markdown">' . $this->parsedown->text($markdown) . '</div>';
+        });
+    }
+}