includes/FeedUtils.php

   1 <?php
   2
   3 /**
   4  * Helper functions for feeds
   5  *
   6  * @ingroup Feed
   7  */
   8 class FeedUtils {
   9
  10         /**
  11          * Check whether feed's cache should be cleared; for changes feeds
  12          * If the feed should be purged; $timekey and $key will be removed from
  13          * $messageMemc
  14          *
  15          * @param $timekey String: cache key of the timestamp of the last item
  16          * @param $key String: cache key of feed's content
  17          */
  18         public static function checkPurge( $timekey, $key ) {
  19                 global $wgRequest, $wgUser, $messageMemc;
  20                 $purge = $wgRequest->getVal( 'action' ) === 'purge';
  21                 if ( $purge && $wgUser->isAllowed('purge') ) {
  22                         $messageMemc->delete( $timekey );
  23                         $messageMemc->delete( $key );
  24                 }
  25         }
  26
  27         /**
  28          * Check whether feeds can be used and that $type is a valid feed type
  29          *
  30          * @param $type String: feed type, as requested by the user
  31          * @return Boolean
  32          */
  33         public static function checkFeedOutput( $type ) {
  34                 global $wgOut, $wgFeed, $wgFeedClasses;
  35
  36                 if ( !$wgFeed ) {
  37                         $wgOut->addWikiMsg( 'feed-unavailable' );
  38                         return false;
  39                 }
  40
  41                 if( !isset( $wgFeedClasses[$type] ) ) {
  42                         $wgOut->addWikiMsg( 'feed-invalid' );
  43                         return false;
  44                 }
  45
  46                 return true;
  47         }
  48
  49         /**
  50          * Format a diff for the newsfeed
  51          *
  52          * @param $row Object: row from the recentchanges table
  53          * @return String
  54          */
  55         public static function formatDiff( $row ) {
  56                 global $wgUser;
  57
  58                 $titleObj = Title::makeTitle( $row->rc_namespace, $row->rc_title );
  59                 $timestamp = wfTimestamp( TS_MW, $row->rc_timestamp );
  60                 $actiontext = '';
  61                 if( $row->rc_type == RC_LOG ) {
  62                         if( $row->rc_deleted & LogPage::DELETED_ACTION ) {
  63                                 $actiontext = wfMsgHtml('rev-deleted-event');
  64                         } else {
  65                                 $actiontext = LogPage::actionText( $row->rc_log_type, $row->rc_log_action,
  66                                         $titleObj, $wgUser->getSkin(), LogPage::extractParams($row->rc_params,true,true) );
  67                         }
  68                 }
  69                 return self::formatDiffRow( $titleObj,
  70                         $row->rc_last_oldid, $row->rc_this_oldid,
  71                         $timestamp,
  72                         ($row->rc_deleted & Revision::DELETED_COMMENT) ? wfMsgHtml('rev-deleted-comment') : $row->rc_comment,
  73                         $actiontext );
  74         }
  75
  76         /**
  77          * Really format a diff for the newsfeed
  78          *
  79          * @param $title Title object
  80          * @param $oldid Integer: old revision's id
  81          * @param $newid Integer: new revision's id
  82          * @param $timestamp Integer: new revision's timestamp
  83          * @param $comment String: new revision's comment
  84          * @param $actiontext String: text of the action; in case of log event
  85          * @return String
  86          */
  87         public static function formatDiffRow( $title, $oldid, $newid, $timestamp, $comment, $actiontext='' ) {
  88                 global $wgFeedDiffCutoff, $wgLang, $wgUser;
  89                 wfProfileIn( __METHOD__ );
  90
  91                 $skin = $wgUser->getSkin();
  92                 # log enties
  93                 $completeText = '<p>' . implode( ' ',
  94                         array_filter(
  95                                 array(
  96                                         $actiontext,
  97                                         $skin->formatComment( $comment ) ) ) ) . "</p>\n";
  98
  99                 //NOTE: Check permissions for anonymous users, not current user.
 100                 //      No "privileged" version should end up in the cache.
 101                 //      Most feed readers will not log in anway.
 102                 $anon = new User();
 103                 $accErrors = $title->getUserPermissionsErrors( 'read', $anon, true );
 104
 105                 # Early exist when the page is not an article, on errors and no newid to
 106                 # compare.
 107                 if( $title->getNamespace() < 0 || $accErrors || !$newid ) {
 108                         wfProfileOut( __METHOD__ );
 109                         return $completeText;
 110                 }
 111
 112                 if( $oldid ) {
 113                         wfProfileIn( __METHOD__."-dodiff" );
 114
 115                         #$diffText = $de->getDiff( wfMsg( 'revisionasof',
 116                         #       $wgLang->timeanddate( $timestamp ),
 117                         #       $wgLang->date( $timestamp ),
 118                         #       $wgLang->time( $timestamp ) ),
 119                         #       wfMsg( 'currentrev' ) );
 120
 121                         // Don't bother generating the diff if we won't be able to show it
 122                         if ( $wgFeedDiffCutoff > 0 ) {
 123                                 $de = new DifferenceEngine( $title, $oldid, $newid );
 124                                 $diffText = $de->getDiff(
 125                                         wfMsg( 'previousrevision' ), // hack
 126                                         wfMsg( 'revisionasof',
 127                                         $wgLang->timeanddate( $timestamp ),
 128                                         $wgLang->date( $timestamp ),
 129                                         $wgLang->time( $timestamp ) ) );
 130                         }
 131
 132                         if ( $wgFeedDiffCutoff <= 0 || ( strlen( $diffText ) > $wgFeedDiffCutoff ) ) {
 133                                 // Omit large diffs
 134                                 $diffText = self::getDiffText( $title, $newid, $oldid);
 135                         } elseif ( $diffText === false ) {
 136                                 // Error in diff engine, probably a missing revision
 137                                 $diffText = "<p>Can't load revision $newid</p>";
 138                         } else {
 139                                 // Diff output fine, clean up any illegal UTF-8
 140                                 $diffText = UtfNormal::cleanUp( $diffText );
 141                                 $diffText = self::applyDiffStyle( $diffText );
 142                         }
 143                         wfProfileOut( __METHOD__."-dodiff" );
 144                 } else {
 145                         $rev = Revision::newFromId( $newid );
 146                         if( $wgFeedDiffCutoff <= 0 || is_null( $rev ) ) {
 147                                 $newtext = '';
 148                         } else {
 149                                 $newtext = $rev->getText();
 150                         }
 151                         if ( $wgFeedDiffCutoff <= 0 || strlen( $newtext ) > $wgFeedDiffCutoff ) {
 152                                 // Omit large new page diffs, bug 29110
 153                                 $diffText = self::getDiffText( $title, $newid );
 154                         } else {
 155                                 $diffText = '<p><b>' . wfMsg( 'newpage' ) . '</b></p>' .
 156                                         '<div>' . nl2br( htmlspecialchars( $newtext ) ) . '</div>';
 157                         }
 158                 }
 159                 $completeText .= $diffText;
 160
 161                 wfProfileOut( __METHOD__ );
 162                 return $completeText;
 163         }
 164
 165         /**
 166          * Generates a diff link. Used when the full diff is not wanted for example
 167          * when $wgFeedDiffCutoff is 0.
 168          *
 169          * @param $title Title object: used to generate the diff URL
 170          * @param $newid Integer newid for this diff
 171          * @param $oldid Integer|null oldid for the diff. Null means it is a new article
 172          */
 173         protected static function getDiffText( Title $title, $newid, $oldid = null ) {
 174                 $queryParameters = ($oldid == null)
 175                         ? "diff={$newid}"
 176                         : "diff={$newid}&oldid={$oldid}" ;
 177                 $diffLink = $title->escapeFullUrl( $queryParameters );
 178
 179                 $diffText = Html::RawElement( 'a', array( 'href' => $diffLink ),
 180                         htmlspecialchars( wfMsgForContent( 'showdiff' ) )
 181                 );
 182
 183                 return $diffText;
 184         }
 185
 186         /**
 187          * Hacky application of diff styles for the feeds.
 188          * Might be 'cleaner' to use DOM or XSLT or something,
 189          * but *gack* it's a pain in the ass.
 190          *
 191          * @param $text String: diff's HTML output
 192          * @return String: modified HTML
 193          */
 194         public static function applyDiffStyle( $text ) {
 195                 $styles = array(
 196                         'diff'             => 'background-color: white; color:black;',
 197                         'diff-otitle'      => 'background-color: white; color:black;',
 198                         'diff-ntitle'      => 'background-color: white; color:black;',
 199                         'diff-addedline'   => 'background: #cfc; color:black; font-size: smaller;',
 200                         'diff-deletedline' => 'background: #ffa; color:black; font-size: smaller;',
 201                         'diff-context'     => 'background: #eee; color:black; font-size: smaller;',
 202                         'diffchange'       => 'color: red; font-weight: bold; text-decoration: none;',
 203                 );
 204
 205                 foreach( $styles as $class => $style ) {
 206                         $text = preg_replace( "/(<[^>]+)class=(['\"])$class\\2([^>]*>)/",
 207                                 "\\1style=\"$style\"\\3", $text );
 208                 }
 209
 210                 return $text;
 211         }
 212
 213 }