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                                         $titleObj, RequestContext::getMain()->getSkin(), LogPage::extractParams($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                 # log enties
  92                 $completeText = '<p>' . implode( ' ',
  93                         array_filter(
  94                                 array(
  95                                         $actiontext,
  96                                         Linker::formatComment( $comment ) ) ) ) . "</p>\n";
  97
  98                 //NOTE: Check permissions for anonymous users, not current user.
  99                 //      No "privileged" version should end up in the cache.
 100                 //      Most feed readers will not log in anway.
 101                 $anon = new User();
 102                 $accErrors = $title->getUserPermissionsErrors( 'read', $anon, true );
 103
 104                 // Can't diff special pages, unreadable pages or pages with no new revision
 105                 // to compare against: just return the text.
 106                 if( $title->getNamespace() < 0 || $accErrors || !$newid ) {
 107                         wfProfileOut( __METHOD__ );
 108                         return $completeText;
 109                 }
 110
 111                 if( $oldid ) {
 112                         wfProfileIn( __METHOD__."-dodiff" );
 113
 114                         #$diffText = $de->getDiff( wfMsg( 'revisionasof',
 115                         #       $wgLang->timeanddate( $timestamp ),
 116                         #       $wgLang->date( $timestamp ),
 117                         #       $wgLang->time( $timestamp ) ),
 118                         #       wfMsg( 'currentrev' ) );
 119
 120                         // Don't bother generating the diff if we won't be able to show it
 121                         if ( $wgFeedDiffCutoff > 0 ) {
 122                                 $de = new DifferenceEngine( $title, $oldid, $newid );
 123                                 $diffText = $de->getDiff(
 124                                         wfMsg( 'previousrevision' ), // hack
 125                                         wfMsg( 'revisionasof',
 126                                         $wgLang->timeanddate( $timestamp ),
 127                                         $wgLang->date( $timestamp ),
 128                                         $wgLang->time( $timestamp ) ) );
 129                         }
 130
 131                         if ( $wgFeedDiffCutoff <= 0 || ( strlen( $diffText ) > $wgFeedDiffCutoff ) ) {
 132                                 // Omit large diffs
 133                                 $diffText = self::getDiffLink( $title, $newid, $oldid );
 134                         } elseif ( $diffText === false ) {
 135                                 // Error in diff engine, probably a missing revision
 136                                 $diffText = "<p>Can't load revision $newid</p>";
 137                         } else {
 138                                 // Diff output fine, clean up any illegal UTF-8
 139                                 $diffText = UtfNormal::cleanUp( $diffText );
 140                                 $diffText = self::applyDiffStyle( $diffText );
 141                         }
 142                         wfProfileOut( __METHOD__."-dodiff" );
 143                 } else {
 144                         $rev = Revision::newFromId( $newid );
 145                         if( $wgFeedDiffCutoff <= 0 || is_null( $rev ) ) {
 146                                 $newtext = '';
 147                         } else {
 148                                 $newtext = $rev->getText();
 149                         }
 150                         if ( $wgFeedDiffCutoff <= 0 || strlen( $newtext ) > $wgFeedDiffCutoff ) {
 151                                 // Omit large new page diffs, bug 29110
 152                                 $diffText = self::getDiffLink( $title, $newid );
 153                         } else {
 154                                 $diffText = '<p><b>' . wfMsg( 'newpage' ) . '</b></p>' .
 155                                         '<div>' . nl2br( htmlspecialchars( $newtext ) ) . '</div>';
 156                         }
 157                 }
 158                 $completeText .= $diffText;
 159
 160                 wfProfileOut( __METHOD__ );
 161                 return $completeText;
 162         }
 163
 164         /**
 165          * Generates a diff link. Used when the full diff is not wanted for example
 166          * when $wgFeedDiffCutoff is 0.
 167          *
 168          * @param $title Title object: used to generate the diff URL
 169          * @param $newid Integer newid for this diff
 170          * @param $oldid Integer|null oldid for the diff. Null means it is a new article
 171          */
 172         protected static function getDiffLink( Title $title, $newid, $oldid = null ) {
 173                 $queryParameters = ($oldid == null)
 174                         ? "diff={$newid}"
 175                         : "diff={$newid}&oldid={$oldid}" ;
 176                 $diffUrl = $title->getFullUrl( $queryParameters );
 177
 178                 $diffLink = Html::element( 'a', array( 'href' => $diffUrl ),
 179                         wfMsgForContent( 'showdiff' ) );
 180
 181                 return $diffLink;
 182         }
 183
 184         /**
 185          * Hacky application of diff styles for the feeds.
 186          * Might be 'cleaner' to use DOM or XSLT or something,
 187          * but *gack* it's a pain in the ass.
 188          *
 189          * @param $text String: diff's HTML output
 190          * @return String: modified HTML
 191          */
 192         public static function applyDiffStyle( $text ) {
 193                 $styles = array(
 194                         'diff'             => 'background-color: white; color:black;',
 195                         'diff-otitle'      => 'background-color: white; color:black;',
 196                         'diff-ntitle'      => 'background-color: white; color:black;',
 197                         'diff-addedline'   => 'background: #cfc; color:black; font-size: smaller;',
 198                         'diff-deletedline' => 'background: #ffa; color:black; font-size: smaller;',
 199                         'diff-context'     => 'background: #eee; color:black; font-size: smaller;',
 200                         'diffchange'       => 'color: red; font-weight: bold; text-decoration: none;',
 201                 );
 202
 203                 foreach( $styles as $class => $style ) {
 204                         $text = preg_replace( "/(<[^>]+)class=(['\"])$class\\2([^>]*>)/",
 205                                 "\\1style=\"$style\"\\3", $text );
 206                 }
 207
 208                 return $text;
 209         }
 210
 211 }