MediaWiki  REL1_23
nextJobDB.php
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00001 <?php
00024 require_once __DIR__ . '/Maintenance.php';
00025 
00031 class NextJobDB extends Maintenance {
00032     public function __construct() {
00033         parent::__construct();
00034         $this->mDescription = "Pick a database that has pending jobs";
00035         $this->addOption( 'type', "Search by job type", false, true );
00036         $this->addOption( 'types', "Space separated list of job types to search for", false, true );
00037     }
00038 
00039     public function execute() {
00040         global $wgJobTypesExcludedFromDefaultQueue;
00041 
00042         // job type required/picked
00043         if ( $this->hasOption( 'types' ) ) {
00044             $types = explode( ' ', $this->getOption( 'types' ) );
00045         } elseif ( $this->hasOption( 'type' ) ) {
00046             $types = array( $this->getOption( 'type' ) );
00047         } else {
00048             $types = false;
00049         }
00050 
00051         // Handle any required periodic queue maintenance
00052         $this->executeReadyPeriodicTasks();
00053 
00054         // Get all the queues with jobs in them
00055         $pendingDBs = JobQueueAggregator::singleton()->getAllReadyWikiQueues();
00056         if ( !count( $pendingDBs ) ) {
00057             return; // no DBs with jobs or cache is both empty and locked
00058         }
00059 
00060         do {
00061             $again = false;
00062 
00063             $candidates = array(); // list of (type, db)
00064             // Flatten the tree of candidates into a flat list so that a random
00065             // item can be selected, weighing each queue (type/db tuple) equally.
00066             foreach ( $pendingDBs as $type => $dbs ) {
00067                 if (
00068                     ( is_array( $types ) && in_array( $type, $types ) ) ||
00069                     ( $types === false && !in_array( $type, $wgJobTypesExcludedFromDefaultQueue ) )
00070                 ) {
00071                     foreach ( $dbs as $db ) {
00072                         $candidates[] = array( $type, $db );
00073                     }
00074                 }
00075             }
00076             if ( !count( $candidates ) ) {
00077                 return; // no jobs for this type
00078             }
00079 
00080             list( $type, $db ) = $candidates[mt_rand( 0, count( $candidates ) - 1 )];
00081         } while ( $again );
00082 
00083         if ( $this->hasOption( 'types' ) ) {
00084             $this->output( $db . " " . $type . "\n" );
00085         } else {
00086             $this->output( $db . "\n" );
00087         }
00088     }
00089 
00094     private function executeReadyPeriodicTasks() {
00095         global $wgLocalDatabases, $wgMemc;
00096 
00097         $count = 0;
00098         $memcKey = 'jobqueue:periodic:lasttime';
00099         $timestamp = (int)$wgMemc->get( $memcKey ); // UNIX timestamp or 0
00100         if ( ( time() - $timestamp ) > 300 || mt_rand( 0, 999 ) == 0 ) { // 5 minutes
00101             if ( $wgMemc->add( "$memcKey:rebuild", 1, 1800 ) ) { // lock
00102                 foreach ( $wgLocalDatabases as $db ) {
00103                     $count += JobQueueGroup::singleton( $db )->executeReadyPeriodicTasks();
00104                 }
00105                 $wgMemc->set( $memcKey, time() );
00106                 $wgMemc->delete( "$memcKey:rebuild" ); // unlock
00107             }
00108         }
00109 
00110         return $count;
00111     }
00112 }
00113 
00114 $maintClass = "NextJobDb";
00115 require_once RUN_MAINTENANCE_IF_MAIN;