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                 $titleObj = Title::makeTitle( $row->rc_namespace, $row->rc_title );
  57                 $timestamp = wfTimestamp( TS_MW, $row->rc_timestamp );
  58                 $actiontext = '';
  59                 if( $row->rc_type == RC_LOG ) {
  60                         if( $row->rc_deleted & LogPage::DELETED_ACTION ) {
  61                                 $actiontext = wfMsgHtml('rev-deleted-event');
  62                         } else {
  63                                 $actiontext = LogPage::actionText( $row->rc_log_type, $row->rc_log_action,
  64                                         $titleObj, RequestContext::getMain()->getSkin(), LogPage::extractParams($row->rc_params,true,true) );
  65                         }
  66                 }
  67                 return self::formatDiffRow( $titleObj,
  68                         $row->rc_last_oldid, $row->rc_this_oldid,
  69                         $timestamp,
  70                         ($row->rc_deleted & Revision::DELETED_COMMENT) ? wfMsgHtml('rev-deleted-comment') : $row->rc_comment,
  71                         $actiontext );
  72         }
  73
  74         /**
  75          * Really format a diff for the newsfeed
  76          *
  77          * @param $title Title object
  78          * @param $oldid Integer: old revision's id
  79          * @param $newid Integer: new revision's id
  80          * @param $timestamp Integer: new revision's timestamp
  81          * @param $comment String: new revision's comment
  82          * @param $actiontext String: text of the action; in case of log event
  83          * @return String
  84          */
  85         public static function formatDiffRow( $title, $oldid, $newid, $timestamp, $comment, $actiontext='' ) {
  86                 global $wgFeedDiffCutoff, $wgLang;
  87                 wfProfileIn( __METHOD__ );
  88
  89                 # log enties
  90                 $completeText = '<p>' . implode( ' ',
  91                         array_filter(
  92                                 array(
  93                                         $actiontext,
  94                                         Linker::formatComment( $comment ) ) ) ) . "</p>\n";
  95
  96                 // NOTE: Check permissions for anonymous users, not current user.
  97                 //       No "privileged" version should end up in the cache.
  98                 //       Most feed readers will not log in anway.
  99                 $anon = new User();
 100                 $accErrors = $title->getUserPermissionsErrors( 'read', $anon, true );
 101
 102                 // Can't diff special pages, unreadable pages or pages with no new revision
 103                 // to compare against: just return the text.
 104                 if( $title->getNamespace() < 0 || $accErrors || !$newid ) {
 105                         wfProfileOut( __METHOD__ );
 106                         return $completeText;
 107                 }
 108
 109                 if( $oldid ) {
 110                         wfProfileIn( __METHOD__."-dodiff" );
 111
 112                         #$diffText = $de->getDiff( wfMsg( 'revisionasof',
 113                         #       $wgLang->timeanddate( $timestamp ),
 114                         #       $wgLang->date( $timestamp ),
 115                         #       $wgLang->time( $timestamp ) ),
 116                         #       wfMsg( 'currentrev' ) );
 117
 118                         // Don't bother generating the diff if we won't be able to show it
 119                         if ( $wgFeedDiffCutoff > 0 ) {
 120                                 $de = new DifferenceEngine( $title, $oldid, $newid );
 121                                 $diffText = $de->getDiff(
 122                                         wfMsg( 'previousrevision' ), // hack
 123                                         wfMsg( 'revisionasof',
 124                                         $wgLang->timeanddate( $timestamp ),
 125                                         $wgLang->date( $timestamp ),
 126                                         $wgLang->time( $timestamp ) ) );
 127                         }
 128
 129                         if ( $wgFeedDiffCutoff <= 0 || ( strlen( $diffText ) > $wgFeedDiffCutoff ) ) {
 130                                 // Omit large diffs
 131                                 $diffText = self::getDiffLink( $title, $newid, $oldid );
 132                         } elseif ( $diffText === false ) {
 133                                 // Error in diff engine, probably a missing revision
 134                                 $diffText = "<p>Can't load revision $newid</p>";
 135                         } else {
 136                                 // Diff output fine, clean up any illegal UTF-8
 137                                 $diffText = UtfNormal::cleanUp( $diffText );
 138                                 $diffText = self::applyDiffStyle( $diffText );
 139                         }
 140                         wfProfileOut( __METHOD__."-dodiff" );
 141                 } else {
 142                         $rev = Revision::newFromId( $newid );
 143                         if( $wgFeedDiffCutoff <= 0 || is_null( $rev ) ) {
 144                                 $newtext = '';
 145                         } else {
 146                                 $newtext = $rev->getText();
 147                         }
 148                         if ( $wgFeedDiffCutoff <= 0 || strlen( $newtext ) > $wgFeedDiffCutoff ) {
 149                                 // Omit large new page diffs, bug 29110
 150                                 $diffText = self::getDiffLink( $title, $newid );
 151                         } else {
 152                                 $diffText = '<p><b>' . wfMsg( 'newpage' ) . '</b></p>' .
 153                                         '<div>' . nl2br( htmlspecialchars( $newtext ) ) . '</div>';
 154                         }
 155                 }
 156                 $completeText .= $diffText;
 157
 158                 wfProfileOut( __METHOD__ );
 159                 return $completeText;
 160         }
 161
 162         /**
 163          * Generates a diff link. Used when the full diff is not wanted for example
 164          * when $wgFeedDiffCutoff is 0.
 165          *
 166          * @param $title Title object: used to generate the diff URL
 167          * @param $newid Integer newid for this diff
 168          * @param $oldid Integer|null oldid for the diff. Null means it is a new article
 169          */
 170         protected static function getDiffLink( Title $title, $newid, $oldid = null ) {
 171                 $queryParameters = ($oldid == null)
 172                         ? "diff={$newid}"
 173                         : "diff={$newid}&oldid={$oldid}" ;
 174                 $diffUrl = $title->getFullUrl( $queryParameters );
 175
 176                 $diffLink = Html::element( 'a', array( 'href' => $diffUrl ),
 177                         wfMsgForContent( 'showdiff' ) );
 178
 179                 return $diffLink;
 180         }
 181
 182         /**
 183          * Hacky application of diff styles for the feeds.
 184          * Might be 'cleaner' to use DOM or XSLT or something,
 185          * but *gack* it's a pain in the ass.
 186          *
 187          * @param $text String: diff's HTML output
 188          * @return String: modified HTML
 189          */
 190         public static function applyDiffStyle( $text ) {
 191                 $styles = array(
 192                         'diff'             => 'background-color: white; color:black;',
 193                         'diff-otitle'      => 'background-color: white; color:black;',
 194                         'diff-ntitle'      => 'background-color: white; color:black;',
 195                         'diff-addedline'   => 'background: #cfc; color:black; font-size: smaller;',
 196                         'diff-deletedline' => 'background: #ffa; color:black; font-size: smaller;',
 197                         'diff-context'     => 'background: #eee; color:black; font-size: smaller;',
 198                         'diffchange'       => 'color: red; font-weight: bold; text-decoration: none;',
 199                 );
 200
 201                 foreach( $styles as $class => $style ) {
 202                         $text = preg_replace( "/(<[^>]+)class=(['\"])$class\\2([^>]*>)/",
 203                                 "\\1style=\"$style\"\\3", $text );
 204                 }
 205
 206                 return $text;
 207         }
 208
 209 }