Merge branch 'main' into issue-3911issue-3911

1 files changed, 326 insertions, 0 deletions

diff --git a/lib/models/OpenGraphURL.php b/lib/models/OpenGraphURL.php
new file mode 100644
index 0000000..29e5718
--- /dev/null
+++ b/lib/models/OpenGraphURL.php
@@ -0,0 +1,326 @@
+<?php
+/*
+ * Copyright (C) 2013 - Rasmus Fuhse <fuhse@data-quest.de>
+ *
+ * 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.
+ */
+
+/**
+ * A model class to handle the database table "opengraphdata", fetch data from
+ * an Opengraph-URL and render a fitting box with the opengraph information to
+ * the user.
+ *
+ * @property int $id alias column for opengraph_id
+ * @property int $opengraph_id database column
+ * @property string $hash database column
+ * @property string $url database column
+ * @property int|null $is_opengraph database column
+ * @property string|null $title database column
+ * @property string|null $image database column
+ * @property string|null $description database column
+ * @property string|null $type database column
+ * @property JSONArrayObject $data database column
+ * @property int $last_update database column
+ * @property int $chdate database column
+ * @property int $mkdate database column
+ */
+class OpenGraphURL extends SimpleORMap
+{
+    const EXPIRES_DURATION = 86400; // = 24 * 60 * 60
+
+    /**
+     * Configures this model.
+     *
+     * @param Array $config Configuration array
+     */
+    protected static function configure($config = [])
+    {
+        $config['db_table'] = 'opengraphdata';
+
+        $config['serialized_fields']['data'] = JSONArrayObject::class;
+
+        parent::configure($config);
+    }
+
+    /**
+     * Create an instance of this model given url. Differs from findOneByURL
+     * insofar that it will return a new object with the given url set
+     * instead of null.
+     *
+     * @param String $url URL to find
+     * @return OpenGraphURL Either existing instance or a new instance for
+     *                      the given url
+     */
+    public static function fromURL($url)
+    {
+        $og = self::findOneByUrl($url);
+        if (!$og) {
+            $og = new self();
+            $og->url = $url;
+        }
+        return $og;
+    }
+
+    /**
+     * Specialized findOneByURL function that uses the hash to find the
+     * appropriate record instead.
+     *
+     * @param  string $url URL to find record for
+     * @return mixed instance of OpenGraphURL if available, null otherwise
+     */
+    public static function findOneByURL($url)
+    {
+        return self::findOneByHash(md5($url));
+    }
+
+    /**
+     * Constructor of the object. Provides a fallback if a url is passed
+     * instead of the usually expected numeric id in order to not break
+     * backward compatibility.
+     * But this constructor will fail miserably if a url is passed that
+     * is not in the database. This was chosen by design to encourage the
+     * correct use of an id.
+     *
+     * @param mixed $id Numeric id, existing url or null
+     */
+    public function __construct($id = null)
+    {
+        // Try to find matching id when an url is passed instead of an id.
+        // This is to ensure that no legacy code will immediately break.
+        if ($id !== null && !ctype_digit($id)) {
+            $temp = self::findOneByUrl($id);
+            if ($temp) {
+                $id = $temp->id;
+            }
+        }
+
+        parent::__construct($id);
+    }
+
+    /**
+     * Sets value of a column. Overwritten so that the hash is also set when
+     * the url is set.
+     *
+     * @param string $field
+     * @param string $value
+     * @return string
+     * @see SimpleORMap::setValue
+     */
+    public function setValue($field, $value)
+    {
+        $ret = parent::setValue($field, $value);
+
+        if ($field === 'url') {
+            $this->content['hash'] = md5($value);
+        }
+
+        return $ret;
+    }
+
+    /**
+     * Stores the object and fetches the opengraph information when either
+     * the object is new or outdated.
+     *
+     * @return int Number of updated records
+     */
+    public function store()
+    {
+        if ($this->isNew() || $this->last_update < time() - self::EXPIRES_DURATION) {
+            // Store last update timestamp BEFORE fetching so another thread
+            // will not fetch again
+            $this->last_update = time();
+            parent::store();
+
+            $this->fetch();
+        }
+
+        return parent::store();
+    }
+
+    /**
+     * Fetches information from the url by getting the contents of the
+     * webpage, parse the webpage and extract the information from the
+     * opengraph meta-tags.
+     * If the site doesn't have any opengraph-metatags it is in fact no
+     * opengraph node and thus no data will be stored in the database.
+     * Only $url['is_opengraph'] === '0' indicates that the site is no
+     * opengraph node at all.
+     *
+     * @todo The combination of FileManager::fetchURLMetadata() and the following request
+     *       leads to two requests for the open graph data. This should
+     *       be fixed due to performance reasons.
+     */
+    public function fetch()
+    {
+        if (!Config::get()->OPENGRAPH_ENABLE) {
+            return;
+        }
+
+        $isOpenGraph = false;
+
+        $response = FileManager::fetchURLMetadata($this['url']);
+        if ((int)$response['response_code'] === 200 && isset($response['Content-Type']) && mb_strpos($response['Content-Type'],'html') !== false) {
+            if (preg_match('/(?<=charset=)[^;]*/i', $response['Content-Type'], $match)) {
+                $currentEncoding = trim($match[0], '"');
+            } else {
+                $currentEncoding = 'UTF-8';
+            }
+
+            $context = get_default_http_stream_context($this['url']);
+            stream_context_set_option($context, [
+                'http' => [
+                    'method' => 'GET',
+                    'header' => sprintf("User-Agent: Stud.IP v%s OpenGraph Parser\r\n", $GLOBALS['SOFTWARE_VERSION']),
+                ],
+            ]);
+
+            $content = @file_get_contents($this['url'], false, $context);
+
+            if ($content === false) {
+                return;
+            }
+
+            $content = mb_encode_numericentity($content, [0x80, 0xffff, 0, 0xffff], $currentEncoding);
+            $old_libxml_error = libxml_use_internal_errors(true);
+            $doc = new DOMDocument();
+            $doc->loadHTML($content);
+            libxml_use_internal_errors($old_libxml_error);
+
+            $metatags = $doc->getElementsByTagName('meta');
+            $reservedTags = ['url', 'chdate', 'mkdate', 'last_update', 'is_opengraph', 'data'];
+            $ogTags = [];
+            $data = [];
+            foreach ($metatags as $tag) {
+                $key = false;
+                if ($tag->hasAttribute('property')
+                    && mb_strpos($tag->getAttribute('property'), 'og:') === 0)
+                {
+                    $key = mb_strtolower(mb_substr($tag->getAttribute('property'), 3));
+                }
+                if (!$key && $tag->hasAttribute('name')
+                    && mb_strpos($tag->getAttribute('name'), 'og:') === 0)
+                {
+                    $key = mb_strtolower(mb_substr($tag->getAttribute('name'), 3));
+                }
+                if ($key) {
+                    $content = $tag->getAttribute('content');
+                    $data[] = ['og:'.$key => $content];
+                    $ogTags[$key] = $content;
+                    $isOpenGraph = true;
+                }
+            }
+            foreach ($ogTags as $key => $tag) {
+                if ($this->isField($key) && !in_array($key, $reservedTags)) {
+                    $this[$key] = $tag;
+                }
+            }
+            if (empty($this['title']) && $isOpenGraph) {
+                $titles = $doc->getElementsByTagName('title');
+                if ($titles->length > 0) {
+                    $this['title'] = $titles->item(0)->textContent;
+                }
+            }
+            if (empty($this['description']) && $isOpenGraph) {
+                foreach ($metatags as $tag) {
+                    if (mb_stripos($tag->getAttribute('name'), "description") !== false
+                        || mb_stripos($tag->getAttribute('property'), "description") !== false)
+                    {
+                        $this['description'] = $tag->getAttribute('content');
+                    }
+                }
+            }
+            $this['data'] = $data;
+        }
+
+        $this['is_opengraph'] = (int) $isOpenGraph;
+    }
+
+    /**
+     * Renders a small box with the information of the opengraph url. Used in
+     * blubber and in the forum.
+     *
+     * @return string html output of the box.
+     */
+    public function render()
+    {
+        if (!Config::get()->OPENGRAPH_ENABLE || !$this->getValue('is_opengraph')) {
+            return '';
+        }
+        $template = $GLOBALS['template_factory']->open('shared/opengraphinfo_wide.php');
+        $template->og = $this;
+        return $template->render();
+    }
+
+    /**
+     * Returns an array with all audiofiles that are provided by the opengraph-node.
+     * Each array-entry is an array itself with the url as first parameter and the
+     * content-type (important for <audio/> tags) as the second.
+     *
+     * @return array(array($url, $content_type), ...)
+     */
+    public function getAudioFiles()
+    {
+        return $this->getMediaFiles('audio');
+    }
+
+    /**
+     * Returns an array with all videofiles that are provided by the opengraph-node.
+     * Each array-entry is an array itself with the url as first parameter and the
+     * content-type (important for <video/> tags) as the second.
+     *
+     * @return array(array($url, $content_type), ...)
+     */
+    public function getVideoFiles()
+    {
+        return $this->getMediaFiles('video');
+    }
+
+    /**
+     * Returns an array with all mediafiles that are provided by the opengraph-node.
+     * Each array-entry is an array itself with the url as first parameter and the
+     * content-type (important for <audio/> or <video/> tags) as the second.
+     *
+     * @param string $type "audio" or "video"
+     * @return array(array($url, $content_type), ...)
+     */
+    protected function getMediaFiles($type)
+    {
+        $files = [];
+        $media = [];
+        $secure_media = [];
+        $media_types = [];
+        foreach ($this['data'] as $meta) {
+            foreach ($meta as $key => $value) {
+                switch ($key) {
+                    case "og:{$type}:url":
+                    case "og:{$type}":
+                        $media[] = $value;
+                        break;
+                    case "og:{$type}:secure_url":
+                        $secure_media[] = $value;
+                        break;
+                    case "og:{$type}:type":
+                        $media_types[] = $value;
+                        break;
+                }
+            }
+        }
+        if (
+            isset($_SERVER['HTTPS'])
+            && $_SERVER['HTTPS'] === 'on'
+            && count($secure_media) > 0
+        ) {
+            foreach ($secure_media as $index => $url) {
+                $files[] = [$url, $media_types[$index]];
+            }
+        } else {
+            foreach ($media as $index => $url) {
+                $files[] = [$url, $media_types[$index]];
+            }
+        }
+        return $files;
+    }
+}