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