includes/Feed.php

   1 <?php
   2 # Basic support for outputting syndication feeds in RSS, other formats
   3 #
   4 # Copyright (C) 2004 Brion Vibber <brion@pobox.com>
   5 # http://www.mediawiki.org/
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 2 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License along
  18 # with this program; if not, write to the Free Software Foundation, Inc.,
  19 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20 # http://www.gnu.org/copyleft/gpl.html
  21
  22 /**
  23  * Contain a feed class as well as classes to build rss / atom ... feeds
  24  * Available feeds are defined in Defines.php
  25  * @package MediaWiki
  26  */
  27
  28
  29 /**
  30  * @todo document
  31  * @package MediaWiki
  32  */
  33 class FeedItem {
  34         /**#@+
  35          * @var string
  36          * @private
  37          */
  38         var $Title = 'Wiki';
  39         var $Description = '';
  40         var $Url = '';
  41         var $Date = '';
  42         var $Author = '';
  43         /**#@-*/
  44
  45         /**#@+
  46          * @todo document
  47          */
  48         function FeedItem( $Title, $Description, $Url, $Date = '', $Author = '', $Comments = '' ) {
  49                 $this->Title = $Title;
  50                 $this->Description = $Description;
  51                 $this->Url = $Url;
  52                 $this->Date = $Date;
  53                 $this->Author = $Author;
  54                 $this->Comments = $Comments;
  55         }
  56
  57         /**
  58          * @static
  59          */
  60         function xmlEncode( $string ) {
  61                 $string = str_replace( "\r\n", "\n", $string );
  62                 $string = preg_replace( '/[\x00-\x08\x0b\x0c\x0e-\x1f]/', '', $string );
  63                 return htmlspecialchars( $string );
  64         }
  65
  66         function getTitle() { return $this->xmlEncode( $this->Title ); }
  67         function getUrl() { return $this->xmlEncode( $this->Url ); }
  68         function getDescription() { return $this->xmlEncode( $this->Description ); }
  69         function getLanguage() {
  70                 global $wgContLanguageCode;
  71                 return $wgContLanguageCode;
  72         }
  73         function getDate() { return $this->Date; }
  74         function getAuthor() { return $this->xmlEncode( $this->Author ); }
  75         function getComments() { return $this->xmlEncode( $this->Comments ); }
  76         /**#@-*/
  77 }
  78
  79 /**
  80  * @todo document
  81  * @package MediaWiki
  82  */
  83 class ChannelFeed extends FeedItem {
  84         /**#@+
  85          * Abstract function, override!
  86          * @abstract
  87          */
  88
  89         /**
  90          * Generate Header of the feed
  91          */
  92         function outHeader() {
  93                 # print "<feed>";
  94         }
  95
  96         /**
  97          * Generate an item
  98          * @param $item
  99          */
 100         function outItem( $item ) {
 101                 # print "<item>...</item>";
 102         }
 103
 104         /**
 105          * Generate Footer of the feed
 106          */
 107         function outFooter() {
 108                 # print "</feed>";
 109         }
 110         /**#@-*/
 111
 112         /**
 113          * Setup and send HTTP headers. Don't send any content;
 114          * content might end up being cached and re-sent with
 115          * these same headers later.
 116          *
 117          * This should be called from the outHeader() method,
 118          * but can also be called separately.
 119          *
 120          * @public
 121          */
 122         function httpHeaders() {
 123                 global $wgOut;
 124
 125                 # We take over from $wgOut, excepting its cache header info
 126                 $wgOut->disable();
 127                 $mimetype = $this->contentType();
 128                 header( "Content-type: $mimetype; charset=UTF-8" );
 129                 $wgOut->sendCacheControl();
 130
 131         }
 132
 133         /**
 134          * Return an internet media type to be sent in the headers.
 135          *
 136          * @return string
 137          * @private
 138          */
 139         function contentType() {
 140                 global $wgRequest;
 141                 $ctype = $wgRequest->getVal('ctype','application/xml');
 142                 $allowedctypes = array('application/xml','text/xml','application/rss+xml','application/atom+xml');
 143                 return (in_array($ctype, $allowedctypes) ? $ctype : 'application/xml');
 144         }
 145
 146         /**
 147          * Output the initial XML headers with a stylesheet for legibility
 148          * if someone finds it in a browser.
 149          * @private
 150          */
 151         function outXmlHeader() {
 152                 global $wgServer, $wgStylePath;
 153
 154                 $this->httpHeaders();
 155                 echo '<?xml version="1.0" encoding="utf-8"?>' . "\n";
 156                 echo '<?xml-stylesheet type="text/css" href="' .
 157                         htmlspecialchars( "$wgServer$wgStylePath/common/feed.css" ) . '"?' . ">\n";
 158         }
 159 }
 160
 161 /**
 162  * Generate a RSS feed
 163  * @todo document
 164  * @package MediaWiki
 165  */
 166 class RSSFeed extends ChannelFeed {
 167
 168         /**
 169          * Format a date given a timestamp
 170          * @param integer $ts Timestamp
 171          * @return string Date string
 172          */
 173         function formatTime( $ts ) {
 174                 return gmdate( 'D, d M Y H:i:s \G\M\T', wfTimestamp( TS_UNIX, $ts ) );
 175         }
 176
 177         /**
 178          * Ouput an RSS 2.0 header
 179          */
 180         function outHeader() {
 181                 global $wgVersion;
 182
 183                 $this->outXmlHeader();
 184                 ?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/">
 185         <channel>
 186                 <title><?php print $this->getTitle() ?></title>
 187                 <link><?php print $this->getUrl() ?></link>
 188                 <description><?php print $this->getDescription() ?></description>
 189                 <language><?php print $this->getLanguage() ?></language>
 190                 <generator>MediaWiki <?php print $wgVersion ?></generator>
 191                 <lastBuildDate><?php print $this->formatTime( wfTimestampNow() ) ?></lastBuildDate>
 192 <?php
 193         }
 194
 195         /**
 196          * Output an RSS 2.0 item
 197          * @param FeedItem item to be output
 198          */
 199         function outItem( $item ) {
 200         ?>
 201                 <item>
 202                         <title><?php print $item->getTitle() ?></title>
 203                         <link><?php print $item->getUrl() ?></link>
 204                         <description><?php print $item->getDescription() ?></description>
 205                         <?php if( $item->getDate() ) { ?><pubDate><?php print $this->formatTime( $item->getDate() ) ?></pubDate><?php } ?>
 206                         <?php if( $item->getAuthor() ) { ?><dc:creator><?php print $item->getAuthor() ?></dc:creator><?php }?>
 207                         <?php if( $item->getComments() ) { ?><comments><?php print $item->getComments() ?></comments><?php }?>
 208                 </item>
 209 <?php
 210         }
 211
 212         /**
 213          * Ouput an RSS 2.0 footer
 214          */
 215         function outFooter() {
 216         ?>
 217         </channel>
 218 </rss><?php
 219         }
 220 }
 221
 222 /**
 223  * Generate an Atom feed
 224  * @todo document
 225  * @package MediaWiki
 226  */
 227 class AtomFeed extends ChannelFeed {
 228         /**
 229          * @todo document
 230          */
 231         function formatTime( $ts ) {
 232                 // need to use RFC 822 time format at least for rss2.0
 233                 return gmdate( 'Y-m-d\TH:i:s', wfTimestamp( TS_UNIX, $ts ) );
 234         }
 235
 236         /**
 237          * Outputs a basic header for Atom 1.0 feeds.
 238          */
 239         function outHeader() {
 240                 global $wgVersion;
 241
 242                 $this->outXmlHeader();
 243                 ?><feed xmlns="http://www.w3.org/2005/Atom" xml:lang="<?php print $this->getLanguage() ?>">
 244                 <id><?php print $this->getFeedId() ?></id>
 245                 <title><?php print $this->getTitle() ?></title>
 246                 <link rel="self" type="application/atom+xml" href="<?php print $this->getSelfUrl() ?>"/>
 247                 <link rel="alternate" type="text/html" href="<?php print $this->getUrl() ?>"/>
 248                 <updated><?php print $this->formatTime( wfTimestampNow() ) ?>Z</updated>
 249                 <subtitle><?php print $this->getDescription() ?></subtitle>
 250                 <generator>MediaWiki <?php print $wgVersion ?></generator>
 251
 252 <?php
 253         }
 254
 255         /**
 256          * Atom 1.0 requires a unique, opaque IRI as a unique indentifier
 257          * for every feed we create. For now just use the URL, but who
 258          * can tell if that's right? If we put options on the feed, do we
 259          * have to change the id? Maybe? Maybe not.
 260          *
 261          * @return string
 262          * @private
 263          */
 264         function getFeedId() {
 265                 return $this->getSelfUrl();
 266         }
 267
 268         /**
 269          * Atom 1.0 requests a self-reference to the feed.
 270          * @return string
 271          * @private
 272          */
 273         function getSelfUrl() {
 274                 global $wgRequest;
 275                 return htmlspecialchars( $wgRequest->getFullRequestURL() );
 276         }
 277
 278         /**
 279          * Output a given item.
 280          * @param $item
 281          */
 282         function outItem( $item ) {
 283                 global $wgMimeType;
 284         ?>
 285         <entry>
 286                 <id><?php print $item->getUrl() ?></id>
 287                 <title><?php print $item->getTitle() ?></title>
 288                 <link rel="alternate" type="<?php print $wgMimeType ?>" href="<?php print $item->getUrl() ?>"/>
 289                 <?php if( $item->getDate() ) { ?>
 290                 <updated><?php print $this->formatTime( $item->getDate() ) ?>Z</updated>
 291                 <?php } ?>
 292
 293                 <summary type="html"><?php print $item->getDescription() ?></summary>
 294                 <?php if( $item->getAuthor() ) { ?><author><name><?php print $item->getAuthor() ?></name></author><?php }?>
 295         </entry>
 296
 297 <?php /* FIXME need to add comments
 298         <?php if( $item->getComments() ) { ?><dc:comment><?php print $item->getComments() ?></dc:comment><?php }?>
 299       */
 300         }
 301
 302         /**
 303          * Outputs the footer for Atom 1.0 feed (basicly '\</feed\>').
 304          */
 305         function outFooter() {?>
 306         </feed><?php
 307         }
 308 }
 309
 310 ?>