QueryPage.php

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<?php

require_once ( "Feed.php" );

# This is a class for doing query pages; since they're almost all the same,
# we factor out some of the functionality into a superclass, and let
# subclasses derive from it.

class QueryPage {
        # Subclasses return their name here. Make sure the name is also
        # specified in SpecialPage.php and in Language.php as a language message param.

        function getName() {
                return "";
        }

        # Subclasses return an SQL query here.
        #
        # Note that the query itself should return the following three columns:
        # 'type' (your special page's name), 'namespace, 'title', and 'value'
        # (numeric) *in that order*. These may be stored in the querycache table
        # for expensive queries, and that cached data will be returned sometimes,
        # so the presence of extra fields can't be relied on.
        #
        # Don't include an ORDER or LIMIT clause, this will be added.

        function getSQL() {
                return "SELECT 'sample' as type, 0 as namespace, 'Sample result' as title, 42 as value";
        }
        
        # Override to sort by increasing values
        function sortDescending() {
                return true;
        }

        # Don't override this unless you're darn sure.
        function getOrderLimit( $offset, $limit ) {
                return " ORDER BY value " .
                        ($this->sortDescending() ? "DESC" : "")
                        . wfLimitResult($limit,$offset);
        }

        # Is this query expensive (for some definition of expensive)? Then we
        # don't let it run in miser mode. $wgDisableQueryPages causes all query
        # pages to be declared expensive. Some query pages are always expensive.
        function isExpensive( ) {
                global $wgDisableQueryPages;
                return $wgDisableQueryPages;
        }

        # Formats the results of the query for display. The skin is the current
        # skin; you can use it for making links. The result is a single row of
        # result data. You should be able to grab SQL results off of it.

        function formatResult( $skin, $result ) {
                return "";
        }
        
        # This is the actual workhorse. It does everything needed to make a
        # real, honest-to-gosh query page.
        
        function doQuery( $offset, $limit ) {
                global $wgUser, $wgOut, $wgLang, $wgRequest;
                global $wgMiserMode;

                $sname = $this->getName();
                $fname = get_class($this) . "::doQuery";
                $sql = $this->getSQL( $offset, $limit );

                $wgOut->setSyndicated( true );
                
                if ( $this->isExpensive() ) {
                        $type = wfStrencode( $sname );
                        $recache = $wgRequest->getBool( "recache" );
                        if( $recache ) {
                                # Clear out any old cached data
                                $res = wfQuery( "DELETE FROM querycache WHERE qc_type='$type'", DB_WRITE, $fname );

                                # Save results into the querycache table
                                $maxstored = 1000;
                                $res = wfQuery(
                                        "INSERT INTO querycache(qc_type,qc_namespace,qc_title,qc_value) " .
                                        $this->getSQL() .
                                        $this->getOrderLimit( 0, $maxstored ),
                                        DB_WRITE, $fname );
                        }
                        if( $wgMiserMode || $recache ) {
                                $sql =
                                        "SELECT qc_type as type, qc_namespace as namespace,qc_title as title, qc_value as value
                                         FROM querycache WHERE qc_type='$type'";
                        }
                        if( $wgMiserMode ) {
                                $wgOut->addWikiText( wfMsg( "perfcached" ) );
                        }
                }

                $res = wfQuery( $sql . $this->getOrderLimit( $offset, $limit ), DB_READ, $fname );
                
                $num = wfNumRows($res);
                
                $sk = $wgUser->getSkin( );

                $top = wfShowingResults( $offset, $num);
                $wgOut->addHTML( "<p>{$top}\n" );

                # often disable 'next' link when we reach the end
                if($num < $limit) { $atend = true; } else { $atend = false; }
                
                $sl = wfViewPrevNext( $offset, $limit , $wgLang->specialPage( $sname ), "" ,$atend );
                $wgOut->addHTML( "<br />{$sl}</p>\n" );

                $s = "<ol start='" . ( $offset + 1 ) . "'>";
                while ( $obj = wfFetchObject( $res ) ) {
                        $format = $this->formatResult( $sk, $obj );
                        $s .= "<li>{$format}</li>\n";
                }
                wfFreeResult( $res );
                $s .= "</ol>";
                $wgOut->addHTML( $s );
                $wgOut->addHTML( "<p>{$sl}</p>\n" );
        }
        
        # Similar to above, but packaging in a syndicated feed instead of a web page
        function doFeed( $class = "" ) {
                global $wgFeedClasses;
                global $wgOut, $wgLanguageCode, $wgLang;
                if( isset($wgFeedClasses[$class]) ) {
                        $feed = new $wgFeedClasses[$class](
                                $this->feedTitle(),
                                $this->feedDesc(),
                                $this->feedUrl() );
                        $feed->outHeader();
                        
                        $sql = $this->getSQL( 0, 50 );
                        $res = wfQuery( $sql, DB_READ, "QueryPage::doFeed" );
                        while( $obj = wfFetchObject( $res ) ) {
                                $item = $this->feedResult( $obj );
                                if( $item ) $feed->outItem( $item );
                        }
                        wfFreeResult( $res );

                        $feed->outFooter();
                        return true;
                } else {
                        return false;
                }
        }

        # Override for custom handling. If the titles/links are ok, just do feedItemDesc()
        function feedResult( $row ) {
                if( !isset( $row->title ) ) {
                        return NULL;
                }
                $title = Title::MakeTitle( IntVal( $row->namespace ), $row->title );
                if( $title ) {
                        if( isset( $row->timestamp ) ) {
                                $date = $row->timestamp;
                        } else {
                                $date = "";
                        }
                        
                        $comments = "";
                        if( $title ) {
                                $talkpage = $title->getTalkPage();
                                $comments = $talkpage->getFullURL();
                        }
                        
                        return new FeedItem(
                                $title->getText(),
                                $this->feedItemDesc( $row ),
                                $title->getFullURL(),
                                $date,
                                $this->feedItemAuthor( $row ),
                                $comments);
                } else {
                        return NULL;
                }
        }
        
        function feedItemDesc( $row ) {
                $text = "";
                if( isset( $row->comment ) ) {
                        $text = htmlspecialchars( $row->comment );
                } else {
                        $text = "";
                }
                
                if( isset( $row->text ) ) {
                        $text = "<p>" . htmlspecialchars( wfMsg( "summary" ) ) . ": " . $text . "</p>\n<hr />\n<div>" .
                                nl2br( htmlspecialchars( $row->text ) ) . "</div>";;
                }
                return $text;
        }
        
        function feedItemAuthor( $row ) {
                if( isset( $row->user_text ) ) {
                        return $row->user_text;
                } else {
                        return "";
                }
        }
        
        function feedTitle() {
                global $wgLanguageCode, $wgSitename, $wgLang;
                $page = SpecialPage::getPage( $this->getName() );
                $desc = $page->getDescription();
                return "$wgSitename - $desc [$wgLanguageCode]";
        }
        
        function feedDesc() {
                return wfMsg( "fromwikipedia" );
        }
        
        function feedUrl() {
                global $wgLang;
                $title = Title::MakeTitle( NS_SPECIAL, $this->getName() );
                return $title->getFullURL();
        }
}

# This is a subclass for very simple queries that are just looking for page
# titles that match some criteria. It formats each result item as a link to
# that page.

class PageQueryPage extends QueryPage {

        function formatResult( $skin, $result ) {
                $nt = Title::makeTitle( $result->namespace, $result->title );
                return $skin->makeKnownLinkObj( $nt, "" );
        }
}

?>

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