Help talk:How To Embed a YouTube Video

Modification

This function depends on an added extension, the following code is saved as a php file named YouTubeTag.php in the extensions folder and require_once('extensions/YouTubeTag.php'); is added to LocalSettings.php. Note that this code is a slight modification of the original in that it allows the width to be specified.

<?php
/*
 * YouTubeTag.php - Provides youtube tag for embedding a YouTube video into a page.
 * @author Jim R. Wilson
 * @version 0.1
 * @copyright Copyright (C) 2007 Jim R. Wilson
 * @license The MIT License - http://www.opensource.org/licenses/mit-license.php 
 * -----------------------------------------------------------------------
 * Description:
 *     This is a MediaWiki extension which adds an additional tag, <youtube>, for embedding
 *     YouTube videos into wiki articles.
 * Requirements:
 *     MediaWiki 1.6.x, 1.8.x, 1.9.x or higher
 *     PHP 4.x, 5.x or higher
 * Installation:
 *     1. Drop this script (YouTubeTag.php) in $IP/extensions
 *         Note: $IP is your MediaWiki install dir.
 *     2. Enable the extension by adding this line to your LocalSettings.php:
 *            require_once('extensions/YouTubeTag.php');
 * Usage:
 *     Once installed, you may utilize YouTubeTag by placing the <youtube> tag in an
 *     article's text:
 *         <youtube v="aYouTubeId" />
 * -----------------------------------------------------------------------
 * Copyright (c) 2007 Jim R. Wilson
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy 
 * of this software and associated documentation files (the "Software"), to deal 
 * in the Software without restriction, including without limitation the rights to 
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of 
 * the Software, and to permit persons to whom the Software is furnished to do 
 * so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all 
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 
 * OTHER DEALINGS IN THE SOFTWARE. 
 * -----------------------------------------------------------------------
 */
 
# Confirm MW environment
if (defined('MEDIAWIKI')) {
 
# Credits
$wgExtensionCredits['parserhook'][] = array(
    'name'=>'YouTubeTag',
    'author'=>'Jim Wilson (wilson.jim.r<at>gmail.com)',
    'url'=>'http://jimbojw.com/wiki/index.php?title=YouTubeTag',
    'description'=>'Provides youtube tag embedding videos into a page.',
    'version'=>'0.1'
);

# Register Extension initializer
$wgExtensionFunctions[] = "wfYouTubeTagExtension";
 
# Extension initializer
function wfYouTubeTagExtension() {
    global $wgParser, $wgMessageCache;
    $wgParser->setHook( "youtube", "renderYouTubeTag" );
    $wgMessageCache->addMessage('youtubetag-bad-id', 'Invalid YouTube video ID supplied: [$1]');
}
 
/**
 * Callback function for embedding video.
 * @param String $input Text between open and close tags - should always be empty or null.
 * @param Array $params Array of tag attributes.
 * @param Parser $parser Instance of Parser performing the parse.
 */
function renderYouTubeTag( $input, $params, &$parser ) {

    # Check for 'v' parameter and ensure it has a valid value
    $v = htmlspecialchars($params['v']);
    if ($v==null || preg_match('%[^A-Za-z0-9_\\-]%',$v)) {
        return '<div class="errorbox">'.wfMsgForContent('youtubetag-bad-id', $v).'</div>';
    }

    # Check for 'width' parameter and ensure it has a valid value
    $width = htmlspecialchars($params['width']);
    if ($width==null || preg_match('[0-9]',$width)) {
        $width=425;
    }
    if ($width==0) {
        $width=425;
    }
    if ($width>1024) {
        $width=1024;
    }
    if ($width<100) {
        $width=100;
    }


    $ratio = 425 / 350;
    $height = round($width / $ratio);

    # Build URL and output embedded flash object
    $url = "http://www.youtube.com/v/$v";
    return
        '<object width="'.$width.'" height="'.$height.'">'.
        '<param name="movie" value="'.$url.'"></param>'.
        '<param name="wmode" value="transparent"></param>'.
        '<embed src="'.$url.'" type="application/x-shockwave-flash" '.
        'wmode="transparent" width="'.$width.'" height="'.$height.'">'.
        '</embed></object>';
}
 
} # Closing MW Environment wrapper