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  * @defgroup Feed Feed
  23  *
  24  * Basic support for outputting syndication feeds in RSS, other formats.
  25  * Contain a feed class as well as classes to build rss / atom ... feeds
  26  * Available feeds are defined in Defines.php
  27  *
  28  * @file
  29  */
  30
  31 /**
  32  * A base class for basic support for outputting syndication feeds in RSS and other formats.
  33  *
  34  * @ingroup Feed
  35  */
  36 class FeedItem {
  37         /**#@+
  38          * @var string
  39          * @private
  40          */
  41         var $Title = 'Wiki';
  42         var $Description = '';
  43         var $Url = '';
  44         var $Date = '';
  45         var $Author = '';
  46         /**#@-*/
  47
  48         /**
  49          * Constructor
  50          *
  51          * @param $Title String: Item's title
  52          * @param $Description String
  53          * @param $Url String: URL uniquely designating the item.
  54          * @param $Date String: Item's date
  55          * @param $Author String: Author's user name
  56          * @param $Comments String
  57          */
  58         function __construct( $Title, $Description, $Url, $Date = '', $Author = '', $Comments = '' ) {
  59                 $this->Title = $Title;
  60                 $this->Description = $Description;
  61                 $this->Url = $Url;
  62                 $this->Date = $Date;
  63                 $this->Author = $Author;
  64                 $this->Comments = $Comments;
  65         }
  66
  67         /**
  68          * Encode $string so that it can be safely embedded in a XML document
  69          *
  70          * @param $string String: string to encode
  71          * @return String
  72          */
  73         public function xmlEncode( $string ) {
  74                 $string = str_replace( "\r\n", "\n", $string );
  75                 $string = preg_replace( '/[\x00-\x08\x0b\x0c\x0e-\x1f]/', '', $string );
  76                 return htmlspecialchars( $string );
  77         }
  78
  79         /**
  80          * Get the title of this item; already xml-encoded
  81          *
  82          * @return String
  83          */
  84         public function getTitle() {
  85                 return $this->xmlEncode( $this->Title );
  86         }
  87
  88         /**
  89          * Get the URL of this item; already xml-encoded
  90          *
  91          * @return String
  92          */
  93         public function getUrl() {
  94                 return $this->xmlEncode( $this->Url );
  95         }
  96
  97         /**
  98          * Get the description of this item; already xml-encoded
  99          *
 100          * @return String
 101          */
 102         public function getDescription() {
 103                 return $this->xmlEncode( $this->Description );
 104         }
 105
 106         /**
 107          * Get the language of this item
 108          *
 109          * @return String
 110          */
 111         public function getLanguage() {
 112                 global $wgContLanguageCode;
 113                 return $wgContLanguageCode;
 114         }
 115
 116         /**
 117          * Get the title of this item
 118          *
 119          * @return String
 120          */
 121         public function getDate() {
 122                 return $this->Date;
 123         }
 124
 125         /**
 126          * Get the author of this item; already xml-encoded
 127          *
 128          * @return String
 129          */
 130         public function getAuthor() {
 131                 return $this->xmlEncode( $this->Author );
 132         }
 133
 134         /**
 135          * Get the comment of this item; already xml-encoded
 136          *
 137          * @return String
 138          */
 139         public function getComments() {
 140                 return $this->xmlEncode( $this->Comments );
 141         }
 142
 143         /**
 144          * Quickie hack... strip out wikilinks to more legible form from the comment.
 145          *
 146          * @param $text String: wikitext
 147          * @return String
 148          */
 149         public static function stripComment( $text ) {
 150                 return preg_replace( '/\[\[([^]]*\|)?([^]]+)\]\]/', '\2', $text );
 151         }
 152         /**#@-*/
 153 }
 154
 155 /**
 156  * @todo document (needs one-sentence top-level class description).
 157  * @ingroup Feed
 158  */
 159 class ChannelFeed extends FeedItem {
 160         /**#@+
 161          * Abstract function, override!
 162          * @abstract
 163          */
 164
 165         /**
 166          * Generate Header of the feed
 167          */
 168         function outHeader() {
 169                 # print "<feed>";
 170         }
 171
 172         /**
 173          * Generate an item
 174          * @param $item
 175          */
 176         function outItem( $item ) {
 177                 # print "<item>...</item>";
 178         }
 179
 180         /**
 181          * Generate Footer of the feed
 182          */
 183         function outFooter() {
 184                 # print "</feed>";
 185         }
 186         /**#@-*/
 187
 188         /**
 189          * Setup and send HTTP headers. Don't send any content;
 190          * content might end up being cached and re-sent with
 191          * these same headers later.
 192          *
 193          * This should be called from the outHeader() method,
 194          * but can also be called separately.
 195          */
 196         public function httpHeaders() {
 197                 global $wgOut;
 198
 199                 # We take over from $wgOut, excepting its cache header info
 200                 $wgOut->disable();
 201                 $mimetype = $this->contentType();
 202                 header( "Content-type: $mimetype; charset=UTF-8" );
 203                 $wgOut->sendCacheControl();
 204
 205         }
 206
 207         /**
 208          * Return an internet media type to be sent in the headers.
 209          *
 210          * @return string
 211          * @private
 212          */
 213         function contentType() {
 214                 global $wgRequest;
 215                 $ctype = $wgRequest->getVal('ctype','application/xml');
 216                 $allowedctypes = array('application/xml','text/xml','application/rss+xml','application/atom+xml');
 217                 return (in_array($ctype, $allowedctypes) ? $ctype : 'application/xml');
 218         }
 219
 220         /**
 221          * Output the initial XML headers with a stylesheet for legibility
 222          * if someone finds it in a browser.
 223          * @private
 224          */
 225         function outXmlHeader() {
 226                 global $wgStylePath, $wgStyleVersion;
 227
 228                 $this->httpHeaders();
 229                 echo '<?xml version="1.0"?>' . "\n";
 230                 echo '<?xml-stylesheet type="text/css" href="' .
 231                         htmlspecialchars( wfExpandUrl( "$wgStylePath/common/feed.css?$wgStyleVersion" ) ) .
 232                         '"?' . ">\n";
 233         }
 234 }
 235
 236 /**
 237  * Generate a RSS feed
 238  *
 239  * @ingroup Feed
 240  */
 241 class RSSFeed extends ChannelFeed {
 242
 243         /**
 244          * Format a date given a timestamp
 245          *
 246          * @param $ts Integer: timestamp
 247          * @return String: date string
 248          */
 249         function formatTime( $ts ) {
 250                 return gmdate( 'D, d M Y H:i:s \G\M\T', wfTimestamp( TS_UNIX, $ts ) );
 251         }
 252
 253         /**
 254          * Ouput an RSS 2.0 header
 255          */
 256         function outHeader() {
 257                 global $wgVersion;
 258
 259                 $this->outXmlHeader();
 260                 ?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/">
 261         <channel>
 262                 <title><?php print $this->getTitle() ?></title>
 263                 <link><?php print $this->getUrl() ?></link>
 264                 <description><?php print $this->getDescription() ?></description>
 265                 <language><?php print $this->getLanguage() ?></language>
 266                 <generator>MediaWiki <?php print $wgVersion ?></generator>
 267                 <lastBuildDate><?php print $this->formatTime( wfTimestampNow() ) ?></lastBuildDate>
 268 <?php
 269         }
 270
 271         /**
 272          * Output an RSS 2.0 item
 273          * @param $item FeedItem: item to be output
 274          */
 275         function outItem( $item ) {
 276         ?>
 277                 <item>
 278                         <title><?php print $item->getTitle() ?></title>
 279                         <link><?php print $item->getUrl() ?></link>
 280                         <description><?php print $item->getDescription() ?></description>
 281                         <?php if( $item->getDate() ) { ?><pubDate><?php print $this->formatTime( $item->getDate() ) ?></pubDate><?php } ?>
 282                         <?php if( $item->getAuthor() ) { ?><dc:creator><?php print $item->getAuthor() ?></dc:creator><?php }?>
 283                         <?php if( $item->getComments() ) { ?><comments><?php print $item->getComments() ?></comments><?php }?>
 284                 </item>
 285 <?php
 286         }
 287
 288         /**
 289          * Ouput an RSS 2.0 footer
 290          */
 291         function outFooter() {
 292         ?>
 293         </channel>
 294 </rss><?php
 295         }
 296 }
 297
 298 /**
 299  * Generate an Atom feed
 300  *
 301  * @ingroup Feed
 302  */
 303 class AtomFeed extends ChannelFeed {
 304         /**
 305          * @todo document
 306          */
 307         function formatTime( $ts ) {
 308                 // need to use RFC 822 time format at least for rss2.0
 309                 return gmdate( 'Y-m-d\TH:i:s', wfTimestamp( TS_UNIX, $ts ) );
 310         }
 311
 312         /**
 313          * Outputs a basic header for Atom 1.0 feeds.
 314          */
 315         function outHeader() {
 316                 global $wgVersion;
 317
 318                 $this->outXmlHeader();
 319                 ?><feed xmlns="http://www.w3.org/2005/Atom" xml:lang="<?php print $this->getLanguage() ?>">
 320                 <id><?php print $this->getFeedId() ?></id>
 321                 <title><?php print $this->getTitle() ?></title>
 322                 <link rel="self" type="application/atom+xml" href="<?php print $this->getSelfUrl() ?>"/>
 323                 <link rel="alternate" type="text/html" href="<?php print $this->getUrl() ?>"/>
 324                 <updated><?php print $this->formatTime( wfTimestampNow() ) ?>Z</updated>
 325                 <subtitle><?php print $this->getDescription() ?></subtitle>
 326                 <generator>MediaWiki <?php print $wgVersion ?></generator>
 327
 328 <?php
 329         }
 330
 331         /**
 332          * Atom 1.0 requires a unique, opaque IRI as a unique indentifier
 333          * for every feed we create. For now just use the URL, but who
 334          * can tell if that's right? If we put options on the feed, do we
 335          * have to change the id? Maybe? Maybe not.
 336          *
 337          * @return string
 338          * @private
 339          */
 340         function getFeedId() {
 341                 return $this->getSelfUrl();
 342         }
 343
 344         /**
 345          * Atom 1.0 requests a self-reference to the feed.
 346          * @return string
 347          * @private
 348          */
 349         function getSelfUrl() {
 350                 global $wgRequest;
 351                 return htmlspecialchars( $wgRequest->getFullRequestURL() );
 352         }
 353
 354         /**
 355          * Output a given item.
 356          * @param $item
 357          */
 358         function outItem( $item ) {
 359                 global $wgMimeType;
 360         ?>
 361         <entry>
 362                 <id><?php print $item->getUrl() ?></id>
 363                 <title><?php print $item->getTitle() ?></title>
 364                 <link rel="alternate" type="<?php print $wgMimeType ?>" href="<?php print $item->getUrl() ?>"/>
 365                 <?php if( $item->getDate() ) { ?>
 366                 <updated><?php print $this->formatTime( $item->getDate() ) ?>Z</updated>
 367                 <?php } ?>
 368
 369                 <summary type="html"><?php print $item->getDescription() ?></summary>
 370                 <?php if( $item->getAuthor() ) { ?><author><name><?php print $item->getAuthor() ?></name></author><?php }?>
 371         </entry>
 372
 373 <?php /* FIXME need to add comments
 374         <?php if( $item->getComments() ) { ?><dc:comment><?php print $item->getComments() ?></dc:comment><?php }?>
 375       */
 376         }
 377
 378         /**
 379          * Outputs the footer for Atom 1.0 feed (basicly '\</feed\>').
 380          */
 381         function outFooter() {?>
 382         </feed><?php
 383         }
 384 }