Mediawiki/Erweiterung/Description

Die Mediawiki-Erweiterung "Description" erzeugt zu jeder Seite eine automatische Beschreibung innerhalb des HTML-Tags "<meta>".

Üblicherweise scheint es sich bei dieser Beschreibung einfach um den ersten Satz der Seite zu handeln. Das sieht dann z. B. so aus:

<meta name="description" content="Die Extension matrix zeigt hunderte von Erweiterungen für Mediawiki." />

Dumm ist allerdings, wenn die Seite mit einer Tabelle anfängt, dann sieht die Beschreibung nämlich so aus:

<meta name="description" content="|-" />

Installation

1. Herunterladen der aktuellen Software unter http://www.mediawiki.org/wiki/Special:ExtensionDistributor/Description

Anlegen des Verzeichnisses "extensions/Description".

# mkdir extensions/Description
# chown wiki:wiki extensions/Description

2. Anlegen der Datei "extensions/Description/Description.php" und Einfügen des folgenden PHP-Codes: Description r36316 (für Mediawiki 13.3).

# vi extensions/Description/Description.php

<?php /** * Description.php -- Adds meaningful description <meta> tag to MW pages * Copyright 2008 Vinismo, Inc. (http://vinismo.com/) * * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * @author Evan Prodromou <evan@vinismo.com> * @addtogroup Extensions */ if (!defined('MEDIAWIKI')) { exit( 1 ); } define('DESCRIPTION_VERSION', '0.1'); $wgExtensionFunctions[] = 'DescriptionSetup'; $wgExtensionCredits['other'][] = array('name' => 'Description', 'version' => DESCRIPTION_VERSION, 'author' => 'Evan Prodromou', 'url' => 'http://www.mediawiki.org/wiki/Extension:Description', 'description' => 'Adds a description meta-tag to MW pages'); function DescriptionSetup() { global $wgHooks; $wgHooks['ArticleViewHeader'][] = 'DescriptionArticleViewHeader'; } function DescriptionArticleViewHeader(&$article, &$outputDone = null, &$pcache = null) { global $wgOut; $desc = DescriptionFromArticle($article); if (!is_null($desc)) { $wgOut->addMeta('description', htmlspecialchars($desc)); } return TRUE; } function DescriptionFromArticle(&$article) { if (defined('MWRDF_VERSION')) { $desc = DescriptionFromRDF($article); } if (is_null($desc) || strlen($desc) == 0) { $desc = DescriptionFromText($article); } return $desc; } function DescriptionFromRDF(&$article) { $nt = $article->getTitle(); $uri = $nt->getFullUrl(); $model = MwRdfGetModel($article); $results = $model->rdqlQuery("SELECT ?description " . "WHERE (<$uri> dc:description ?description) " . "USING dc FOR http://purl.org/dc/elements/1.1/", FALSE); $desc = ''; foreach ($results as $row) { $rowval = preg_replace("/^\"(.*?)\"$/", '\1', $row['?description']); $desc .= (($desc) ? ' ' : '') . $rowval; } return $desc; } function DescriptionFromText(&$article) { global $wgParser, $wgContLang; # Expand all templates $text = $article->getContent(true); $text = $wgParser->preprocess($text, $article->mTitle, new ParserOptions()); # Find first non-ws, non-empty, non-image, non-table content $imageLabel = $wgContLang->getNsText(NS_IMAGE); $paragraphs = explode("\n", $text); $desc = ''; foreach ($paragraphs as $paragraph) { if (preg_match("/^\s*(=|__|\[\[[Ii]mage:|\[\[$imageLabel:|\{\||\|#|\*)/", $paragraph)) { continue; } else if (preg_match("/^\s*$/", $paragraph)) { continue; } else { $desc = DescriptionStripParagraph($paragraph); break; } } return $desc; } function DescriptionStripParagraph($para) { $para = preg_replace("/'''''(.*?)'''''/", '\1', $para); $para = preg_replace("/'''(.*?)'''/", '\1', $para); $para = preg_replace("/''(.*?)''/", '\1', $para); $para = preg_replace("@<(.*?)>(.*?)</\1>@", '\2', $para); $para = preg_replace("/\[\[([^\]]*?)\|([^\]]*?)\]\]/", '\2', $para); $para = preg_replace("/\[\[([^\]]*?)\]\]/", '\1', $para); $para = preg_replace("/\[(\S*)\s+(.*?)\]/", '\2', $para); $para = preg_replace("/\[(\S*)\s*\]/", '\1', $para); return $para; } ?>

4. Anpassung der Rechte.

# chown wiki:wiki extensions/Description/Description.php

5. Einfügen der folgenden Zeile in die Datei "LocalSettings.php".

## Extension: Description
require_once("$IP/extensions/Description/Description.php");

Weblinks

• Description