<?php
/**
* Helper functions for feeds.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Feed
*/
/**
* Helper functions for feeds
*
* @ingroup Feed
*/
class FeedUtils {
/**
* Check whether feed's cache should be cleared; for changes feeds
* If the feed should be purged; $timekey and $key will be removed from
* $messageMemc
*
* @param string $timekey cache key of the timestamp of the last item
* @param string $key cache key of feed's content
*/
public static function checkPurge( $timekey, $key ) {
global $wgRequest, $wgUser, $messageMemc;
$purge = $wgRequest->getVal( 'action' ) === 'purge';
if ( $purge && $wgUser->isAllowed( 'purge' ) ) {
$messageMemc->delete( $timekey );
$messageMemc->delete( $key );
}
}
/**
* Check whether feeds can be used and that $type is a valid feed type
*
* @param string $type feed type, as requested by the user
* @return Boolean
*/
public static function checkFeedOutput( $type ) {
global $wgOut, $wgFeed, $wgFeedClasses;
if ( !$wgFeed ) {
$wgOut->addWikiMsg( 'feed-unavailable' );
return false;
}
if ( !isset( $wgFeedClasses[$type] ) ) {
$wgOut->addWikiMsg( 'feed-invalid' );
return false;
}
return true;
}
/**
* Format a diff for the newsfeed
*
* @param $row Object: row from the recentchanges table
* @return String
*/
public static function formatDiff( $row ) {
$titleObj = Title::makeTitle( $row->rc_namespace, $row->rc_title );
$timestamp = wfTimestamp( TS_MW, $row->rc_timestamp );
$actiontext = '';
if ( $row->rc_type == RC_LOG ) {
$rcRow = (array)$row; // newFromRow() only accepts arrays for RC rows
$actiontext = LogFormatter::newFromRow( $rcRow )->getActionText();
}
return self::formatDiffRow( $titleObj,
$row->rc_last_oldid, $row->rc_this_oldid,
$timestamp,
$row->rc_deleted & Revision::DELETED_COMMENT
? wfMessage( 'rev-deleted-comment' )->escaped()
: $row->rc_comment,
$actiontext
);
}
/**
* Really format a diff for the newsfeed
*
* @param $title Title object
* @param $oldid Integer: old revision's id
* @param $newid Integer: new revision's id
* @param $timestamp Integer: new revision's timestamp
* @param string $comment new revision's comment
* @param string $actiontext text of the action; in case of log event
* @return String
*/
public static function formatDiffRow( $title, $oldid, $newid, $timestamp, $comment, $actiontext = '' ) {
global $wgFeedDiffCutoff, $wgLang;
wfProfileIn( __METHOD__ );
// log entries
$completeText = '<p>' . implode( ' ',
array_filter(
array(
$actiontext,
Linker::formatComment( $comment ) ) ) ) . "</p>\n";
// NOTE: Check permissions for anonymous users, not current user.
// No "privileged" version should end up in the cache.
// Most feed readers will not log in anyway.
$anon = new User();
$accErrors = $title->getUserPermissionsErrors( 'read', $anon, true );
// Can't diff special pages, unreadable pages or pages with no new revision
// to compare against: just return the text.
if ( $title->getNamespace() < 0 || $accErrors || !$newid ) {
wfProfileOut( __METHOD__ );
return $completeText;
}
if ( $oldid ) {
wfProfileIn( __METHOD__ . "-dodiff" );
#$diffText = $de->getDiff( wfMessage( 'revisionasof',
# $wgLang->timeanddate( $timestamp ),
# $wgLang->date( $timestamp ),
# $wgLang->time( $timestamp ) )->text(),
# wfMessage( 'currentrev' )->text() );
$diffText = '';
// Don't bother generating the diff if we won't be able to show it
if ( $wgFeedDiffCutoff > 0 ) {
$rev = Revision::newFromId( $oldid );
if ( !$rev ) {
$diffText = false;
} else {
$context = clone RequestContext::getMain();
$context->setTitle( $title );
$contentHandler = $rev->getContentHandler();
$de = $contentHandler->createDifferenceEngine( $context, $oldid, $newid );
$diffText = $de->getDiff(
wfMessage( 'previousrevision' )->text(), // hack
wfMessage( 'revisionasof',
$wgLang->timeanddate( $timestamp ),
$wgLang->date( $timestamp ),
$wgLang->time( $timestamp ) )->text() );
}
}
if ( $wgFeedDiffCutoff <= 0 || ( strlen( $diffText ) > $wgFeedDiffCutoff ) ) {
// Omit large diffs
$diffText = self::getDiffLink( $title, $newid, $oldid );
} elseif ( $diffText === false ) {
// Error in diff engine, probably a missing revision
$diffText = "<p>Can't load revision $newid</p>";
} else {
// Diff output fine, clean up any illegal UTF-8
$diffText = UtfNormal::cleanUp( $diffText );
$diffText = self::applyDiffStyle( $diffText );
}
wfProfileOut( __METHOD__ . "-dodiff" );
} else {
$rev = Revision::newFromId( $newid );
if ( $wgFeedDiffCutoff <= 0 || is_null( $rev ) ) {
$newContent = ContentHandler::getForTitle( $title )->makeEmptyContent();
} else {
$newContent = $rev->getContent();
}
if ( $newContent instanceof TextContent ) {
// only textual content has a "source view".
$text = $newContent->getNativeData();
if ( $wgFeedDiffCutoff <= 0 || strlen( $text ) > $wgFeedDiffCutoff ) {
$html = null;
} else {
$html = nl2br( htmlspecialchars( $text ) );
}
} else {
//XXX: we could get an HTML representation of the content via getParserOutput, but that may
// contain JS magic and generally may not be suitable for inclusion in a feed.
// Perhaps Content should have a getDescriptiveHtml method and/or a getSourceText method.
//Compare also ApiFeedContributions::feedItemDesc
$html = null;
}
if ( $html === null ) {
// Omit large new page diffs, bug 29110
// Also use diff link for non-textual content
$diffText = self::getDiffLink( $title, $newid );
} else {
$diffText = '<p><b>' . wfMessage( 'newpage' )->text() . '</b></p>' .
'<div>' . $html . '</div>';
}
}
$completeText .= $diffText;
wfProfileOut( __METHOD__ );
return $completeText;
}
/**
* Generates a diff link. Used when the full diff is not wanted for example
* when $wgFeedDiffCutoff is 0.
*
* @param $title Title object: used to generate the diff URL
* @param $newid Integer newid for this diff
* @param $oldid Integer|null oldid for the diff. Null means it is a new article
* @return string
*/
protected static function getDiffLink( Title $title, $newid, $oldid = null ) {
$queryParameters = array( 'diff' => $newid );
if ( $oldid != null ) {
$queryParameters['oldid'] = $oldid;
}
$diffUrl = $title->getFullURL( $queryParameters );
$diffLink = Html::element( 'a', array( 'href' => $diffUrl ),
wfMessage( 'showdiff' )->inContentLanguage()->text() );
return $diffLink;
}
/**
* Hacky application of diff styles for the feeds.
* Might be 'cleaner' to use DOM or XSLT or something,
* but *gack* it's a pain in the ass.
*
* @param string $text diff's HTML output
* @return String: modified HTML
*/
public static function applyDiffStyle( $text ) {
$styles = array(
'diff' => 'background-color: white; color:black;',
'diff-otitle' => 'background-color: white; color:black; text-align: center;',
'diff-ntitle' => 'background-color: white; color:black; text-align: center;',
'diff-addedline' => 'color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;',
'diff-deletedline' => 'color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;',
'diff-context' => 'background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;',
'diffchange' => 'font-weight: bold; text-decoration: none;',
);
foreach ( $styles as $class => $style ) {
$text = preg_replace( "/(<[^>]+)class=(['\"])$class\\2([^>]*>)/",
"\\1style=\"$style\"\\3", $text );
}
return $text;
}
}