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