includes/QueryPage.php

   1 <?php
   2
   3 require_once ( "Feed.php" );
   4
   5 # This is a class for doing query pages; since they're almost all the same,
   6 # we factor out some of the functionality into a superclass, and let
   7 # subclasses derive from it.
   8
   9 class QueryPage {
  10         # Subclasses return their name here. Make sure the name is also
  11         # specified in SpecialPage.php and in Language.php as a language message param.
  12
  13         function getName() {
  14                 return "";
  15         }
  16
  17         # Subclasses return an SQL query here.
  18         #
  19         # Note that the query itself should return the following three columns:
  20         # 'type' (your special page's name), 'namespace, 'title', and 'value'
  21         # (numeric) *in that order*. These may be stored in the querycache table
  22         # for expensive queries, and that cached data will be returned sometimes,
  23         # so the presence of extra fields can't be relied on.
  24         #
  25         # Don't include an ORDER or LIMIT clause, this will be added.
  26
  27         function getSQL() {
  28                 return "SELECT 'sample' as type, 0 as namespace, 'Sample result' as title, 42 as value";
  29         }
  30
  31         # Override to sort by increasing values
  32         function sortDescending() {
  33                 return true;
  34         }
  35
  36         # Don't override this unless you're darn sure.
  37         function getOrderLimit( $offset, $limit ) {
  38                 return " ORDER BY value " .
  39                         ($this->sortDescending() ? "DESC" : "")
  40                         . wfLimitResult($limit,$offset);
  41         }
  42
  43         # Is this query expensive (for some definition of expensive)? Then we
  44         # don't let it run in miser mode. $wgDisableQueryPages causes all query
  45         # pages to be declared expensive. Some query pages are always expensive.
  46         function isExpensive( ) {
  47                 global $wgDisableQueryPages;
  48                 return $wgDisableQueryPages;
  49         }
  50
  51         # Formats the results of the query for display. The skin is the current
  52         # skin; you can use it for making links. The result is a single row of
  53         # result data. You should be able to grab SQL results off of it.
  54
  55         function formatResult( $skin, $result ) {
  56                 return "";
  57         }
  58
  59         # This is the actual workhorse. It does everything needed to make a
  60         # real, honest-to-gosh query page.
  61
  62         function doQuery( $offset, $limit ) {
  63                 global $wgUser, $wgOut, $wgLang, $wgRequest;
  64                 global $wgMiserMode;
  65
  66                 $sname = $this->getName();
  67                 $fname = get_class($this) . "::doQuery";
  68                 $sql = $this->getSQL();
  69                 $dbr =& wfGetDB( DB_SLAVE );
  70                 $dbw =& wfGetDB( DB_MASTER );
  71                 $querycache = $dbr->tableName( 'querycache' );
  72
  73                 $wgOut->setSyndicated( true );
  74                 $res = false;
  75
  76                 if ( $this->isExpensive() ) {
  77                         $recache = $wgRequest->getBool( "recache" );
  78                         if( $recache ) {
  79                                 # Clear out any old cached data
  80                                 $dbw->delete( 'querycache', array( 'qc_type' => $sname ), $fname );
  81
  82                                 # Do query on the (possibly out of date) slave server
  83                                 $maxstored = 1000;
  84                                 $res = $dbr->query( $sql . $this->getOrderLimit( 0, $maxstored ), $fname );
  85
  86                                 # Fetch results
  87                                 $insertSql = "INSERT INTO $querycache (qc_type,qc_namespace,qc_title,qc_value) VALUES ";
  88                                 $first = true;
  89                                 while ( $row = $dbr->fetchObject( $res ) ) {
  90                                         if ( $first ) {
  91                                                 $first = false;
  92                                         } else {
  93                                                 $insertSql .= ",";
  94                                         }
  95                                         $insertSql .= "(" .
  96                                                 $dbw->addQuotes( $row->type ) . "," .
  97                                                 $dbw->addQuotes( $row->namespace ) . "," .
  98                                                 $dbw->addQuotes( $row->title ) . "," .
  99                                                 $dbw->addQuotes( $row->value ) . ")";
 100                                 }
 101
 102                                 # Save results into the querycache table on the master
 103                                 $dbw->query( $insertSql, $fname );
 104
 105                                 # Set result pointer to allow reading for display
 106                                 $numRows = $dbr->numRows( $res );
 107                                 if ( $numRows <= $offset ) {
 108                                         $num = 0;
 109                                 } else {
 110                                         $dbr->dataSeek( $res, $offset );
 111                                         $num = max( $limit, $numRows - $offset );
 112                                 }
 113                         }
 114                         if( $wgMiserMode || $recache ) {
 115                                 $type = $dbr->strencdode( $sname );
 116                                 $sql =
 117                                         "SELECT qc_type as type, qc_namespace as namespace,qc_title as title, qc_value as value
 118                                          FROM $querycache WHERE qc_type='$type'";
 119                         }
 120                         if( $wgMiserMode ) {
 121                                 $wgOut->addWikiText( wfMsg( "perfcached" ) );
 122                         }
 123                 }
 124                 if ( $res === false ) {
 125                         $res = $dbr->query( $sql . $this->getOrderLimit( $offset, $limit ), $fname );
 126                         $num = $dbr->numRows($res);
 127                 }
 128
 129
 130                 $sk = $wgUser->getSkin( );
 131
 132                 $top = wfShowingResults( $offset, $num);
 133                 $wgOut->addHTML( "<p>{$top}\n" );
 134
 135                 # often disable 'next' link when we reach the end
 136                 if($num < $limit) { $atend = true; } else { $atend = false; }
 137
 138                 $sl = wfViewPrevNext( $offset, $limit , $wgLang->specialPage( $sname ), "" ,$atend );
 139                 $wgOut->addHTML( "<br />{$sl}</p>\n" );
 140
 141                 $s = "<ol start='" . ( $offset + 1 ) . "'>";
 142                 # Only read at most $num rows, because $res may contain the whole 1000
 143                 for ( $i = 0; $i < $num && $obj = $dbr->fetchObject( $res ); $i++ ) {
 144                         $format = $this->formatResult( $sk, $obj );
 145                         $s .= "<li>{$format}</li>\n";
 146                 }
 147                 $dbr->freeResult( $res );
 148                 $s .= "</ol>";
 149                 $wgOut->addHTML( $s );
 150                 $wgOut->addHTML( "<p>{$sl}</p>\n" );
 151         }
 152
 153         # Similar to above, but packaging in a syndicated feed instead of a web page
 154         function doFeed( $class = "" ) {
 155                 global $wgFeedClasses;
 156                 global $wgOut, $wgLanguageCode, $wgLang;
 157                 if( isset($wgFeedClasses[$class]) ) {
 158                         $feed = new $wgFeedClasses[$class](
 159                                 $this->feedTitle(),
 160                                 $this->feedDesc(),
 161                                 $this->feedUrl() );
 162                         $feed->outHeader();
 163
 164                         $dbr =& wfGetDB( DB_SLAVE );
 165                         $sql = $this->getSQL() . $this->getOrderLimit( 0, 50 );
 166                         $res = $dbr->query( $sql, "QueryPage::doFeed" );
 167                         while( $obj = $dbr->fetchObject( $res ) ) {
 168                                 $item = $this->feedResult( $obj );
 169                                 if( $item ) $feed->outItem( $item );
 170                         }
 171                         $dbr->freeResult( $res );
 172
 173                         $feed->outFooter();
 174                         return true;
 175                 } else {
 176                         return false;
 177                 }
 178         }
 179
 180         # Override for custom handling. If the titles/links are ok, just do feedItemDesc()
 181         function feedResult( $row ) {
 182                 if( !isset( $row->title ) ) {
 183                         return NULL;
 184                 }
 185                 $title = Title::MakeTitle( IntVal( $row->namespace ), $row->title );
 186                 if( $title ) {
 187                         if( isset( $row->timestamp ) ) {
 188                                 $date = $row->timestamp;
 189                         } else {
 190                                 $date = "";
 191                         }
 192
 193                         $comments = "";
 194                         if( $title ) {
 195                                 $talkpage = $title->getTalkPage();
 196                                 $comments = $talkpage->getFullURL();
 197                         }
 198
 199                         return new FeedItem(
 200                                 $title->getText(),
 201                                 $this->feedItemDesc( $row ),
 202                                 $title->getFullURL(),
 203                                 $date,
 204                                 $this->feedItemAuthor( $row ),
 205                                 $comments);
 206                 } else {
 207                         return NULL;
 208                 }
 209         }
 210
 211         function feedItemDesc( $row ) {
 212                 $text = "";
 213                 if( isset( $row->comment ) ) {
 214                         $text = htmlspecialchars( $row->comment );
 215                 } else {
 216                         $text = "";
 217                 }
 218
 219                 if( isset( $row->text ) ) {
 220                         $text = "<p>" . htmlspecialchars( wfMsg( "summary" ) ) . ": " . $text . "</p>\n<hr />\n<div>" .
 221                                 nl2br( htmlspecialchars( $row->text ) ) . "</div>";;
 222                 }
 223                 return $text;
 224         }
 225
 226         function feedItemAuthor( $row ) {
 227                 if( isset( $row->user_text ) ) {
 228                         return $row->user_text;
 229                 } else {
 230                         return "";
 231                 }
 232         }
 233
 234         function feedTitle() {
 235                 global $wgLanguageCode, $wgSitename, $wgLang;
 236                 $page = SpecialPage::getPage( $this->getName() );
 237                 $desc = $page->getDescription();
 238                 return "$wgSitename - $desc [$wgLanguageCode]";
 239         }
 240
 241         function feedDesc() {
 242                 return wfMsg( "fromwikipedia" );
 243         }
 244
 245         function feedUrl() {
 246                 global $wgLang;
 247                 $title = Title::MakeTitle( NS_SPECIAL, $this->getName() );
 248                 return $title->getFullURL();
 249         }
 250 }
 251
 252 # This is a subclass for very simple queries that are just looking for page
 253 # titles that match some criteria. It formats each result item as a link to
 254 # that page.
 255
 256 class PageQueryPage extends QueryPage {
 257
 258         function formatResult( $skin, $result ) {
 259                 $nt = Title::makeTitle( $result->namespace, $result->title );
 260                 return $skin->makeKnownLinkObj( $nt, "" );
 261         }
 262 }
 263
 264 ?>