maintenance/nextJobDB.php

   1 <?php
   2
   3 /*
   4  * Pick a database that has pending jobs
   5  */
   6
   7 $options = array( 'type'  );
   8
   9 require_once( 'commandLine.inc' );
  10
  11 $type = isset($options['type'])
  12                 ? $options['type']
  13                 : false;
  14
  15 $mckey = $type === false
  16             ? "jobqueue:dbs"
  17             : "jobqueue:dbs:$type";
  18
  19 $pendingDBs = $wgMemc->get( $mckey );
  20 if ( !$pendingDBs ) {
  21         $pendingDBs = array();
  22         # Cross-reference DBs by master DB server
  23         $dbsByMaster = array();
  24         foreach ( $wgLocalDatabases as $db ) {
  25                 $lb = wfGetLB( $db );
  26                 $dbsByMaster[$lb->getServerName(0)][] = $db;
  27         }
  28
  29         foreach ( $dbsByMaster as $master => $dbs ) {
  30                 $dbConn = wfGetDB( DB_MASTER, array(), $dbs[0] );
  31                 $stype = $dbConn->addQuotes($type);
  32
  33                 # Padding row for MySQL bug
  34                 $sql = "(SELECT '-------------------------------------------')";
  35                 foreach ( $dbs as $dbName ) {
  36                         if ( $sql != '' ) {
  37                                 $sql .= ' UNION ';
  38                         }
  39                         if ($type === false)
  40                                 $sql .= "(SELECT '$dbName' FROM `$dbName`.job LIMIT 1)";
  41                         else
  42                                 $sql .= "(SELECT '$dbName' FROM `$dbName`.job WHERE job_cmd=$stype LIMIT 1)";
  43                 }
  44                 $res = $dbConn->query( $sql, 'nextJobDB.php' );
  45                 $row = $dbConn->fetchRow( $res ); // discard padding row
  46                 while ( $row = $dbConn->fetchRow( $res ) ) {
  47                         $pendingDBs[] = $row[0];
  48                 }
  49         }
  50
  51         $wgMemc->set( $mckey, $pendingDBs, 300 );
  52 }
  53
  54 if ( $pendingDBs ) {
  55         echo $pendingDBs[mt_rand(0, count( $pendingDBs ) - 1)];
  56 }
  57
  58