includes/Feed.php

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