maintenance/nextJobDB.php

   1 <?php
   2 /**
   3  * Pick a database that has pending jobs
   4  *
   5  * @file
   6  * @ingroup Maintenance
   7  */
   8
   9 require_once( "Maintenance.php" );
  10
  11 class nextJobDB extends Maintenance {
  12         public function __construct() {
  13                 parent::__construct();
  14                 $this->mDescription = "Pick a database that has pending jobs";
  15                 $this->addParam( 'type', "The type of job to search for", false, true );
  16         }
  17         public function execute() {
  18                 global $wgMemc;
  19                 $type = $this->getParam( 'type', false );
  20                 $mckey = $type === false
  21                                         ? "jobqueue:dbs"
  22                                         : "jobqueue:dbs:$type";
  23                 $pendingDBs = $wgMemcKey->get( $mckey );
  24
  25                 # If we didn't get it from the cache
  26                 if( !$pendingDBs ) {
  27                         $pendingDBs = $this->getPendingDbs( $type );
  28                         $wgMemc->get( $mckey, $pendingDBs, 300 )
  29                 }
  30                 # If we've got a pending job in a db, display it.
  31                 if ( $pendingDBs ) {
  32                         $this->output( $pendingDBs[mt_rand(0, count( $pendingDBs ) - 1)] );
  33                 }
  34         }
  35
  36         /**
  37          * Get all databases that have a pending job
  38          * @param $type String Job type
  39          * @return array
  40          */
  41         private function getPendingDbs( $type ) {
  42                 $pendingDBs = array();
  43                 # Cross-reference DBs by master DB server
  44                 $dbsByMaster = array();
  45                 foreach ( $wgLocalDatabases as $db ) {
  46                         $lb = wfGetLB( $db );
  47                         $dbsByMaster[$lb->getServerName(0)][] = $db;
  48                 }
  49
  50                 foreach ( $dbsByMaster as $master => $dbs ) {
  51                         $dbConn = wfGetDB( DB_MASTER, array(), $dbs[0] );
  52                         $stype = $dbConn->addQuotes($type);
  53                         $jobTable = $dbConn->getTable( 'job' );
  54
  55                         # Padding row for MySQL bug
  56                         $sql = "(SELECT '-------------------------------------------')";
  57                         foreach ( $dbs as $dbName ) {
  58                                 if ( $sql != '' ) {
  59                                         $sql .= ' UNION ';
  60                                 }
  61                                 if ($type === false)
  62                                         $sql .= "(SELECT '$dbName' FROM `$dbName`.$jobTable LIMIT 1)";
  63                                 else
  64                                         $sql .= "(SELECT '$dbName' FROM `$dbName`.$jobTable WHERE job_cmd=$stype LIMIT 1)";
  65                         }
  66                         $res = $dbConn->query( $sql, __METHOD__ );
  67                         $row = $dbConn->fetchRow( $res ); // discard padding row
  68                         while ( $row = $dbConn->fetchRow( $res ) ) {
  69                                 $pendingDBs[] = $row[0];
  70                         }
  71                 }
  72         }
  73 }
  74
  75 $maintClass = "nextJobDb";
  76 require_once( DO_MAINTENANCE );