- list( $dbw, $scope ) = $this->getMasterDB();
- $dbw->commit( __METHOD__, 'flush' ); // flush existing transaction
- $autoTrx = $dbw->getFlag( DBO_TRX ); // get current setting
- $dbw->clearFlag( DBO_TRX ); // make each query its own transaction
- $scopedReset = new ScopedCallback( function() use ( $dbw, $autoTrx ) {
- $dbw->setFlag( $autoTrx ? DBO_TRX : 0 ); // restore old setting
- } );
-
- $uuid = wfRandomString( 32 ); // pop attempt
- $job = false; // job popped off
- do { // retry when our row is invalid or deleted as a duplicate
- // Try to reserve a row in the DB...
- if ( in_array( $this->order, array( 'fifo', 'timestamp' ) ) ) {
- $row = $this->claimOldest( $uuid );
- } else { // random first
- $rand = mt_rand( 0, self::MAX_JOB_RANDOM ); // encourage concurrent UPDATEs
- $gte = (bool)mt_rand( 0, 1 ); // find rows with rand before/after $rand
- $row = $this->claimRandom( $uuid, $rand, $gte );
- }
- // Check if we found a row to reserve...
- if ( !$row ) {
- $this->cache->set( $this->getCacheKey( 'empty' ), 'true', self::CACHE_TTL_LONG );
- break; // nothing to do
- }
- JobQueue::incrStats( 'job-pop', $this->type );
- // Get the job object from the row...
- $title = Title::makeTitleSafe( $row->job_namespace, $row->job_title );
- if ( !$title ) {
- $dbw->delete( 'job', array( 'job_id' => $row->job_id ), __METHOD__ );
- wfDebug( "Row has invalid title '{$row->job_title}'." );
- continue; // try again
- }
- $job = Job::factory( $row->job_cmd, $title,
- self::extractBlob( $row->job_params ), $row->job_id );
- $job->metadata['id'] = $row->job_id;
- $job->id = $row->job_id; // XXX: work around broken subclasses
- break; // done
- } while ( true );
+ $dbw = $this->getMasterDB();
+ try {
+ $dbw->commit( __METHOD__, 'flush' ); // flush existing transaction
+ $autoTrx = $dbw->getFlag( DBO_TRX ); // get current setting
+ $dbw->clearFlag( DBO_TRX ); // make each query its own transaction
+ $scopedReset = new ScopedCallback( function() use ( $dbw, $autoTrx ) {
+ $dbw->setFlag( $autoTrx ? DBO_TRX : 0 ); // restore old setting
+ } );
+
+ $uuid = wfRandomString( 32 ); // pop attempt
+ $job = false; // job popped off
+ do { // retry when our row is invalid or deleted as a duplicate
+ // Try to reserve a row in the DB...
+ if ( in_array( $this->order, array( 'fifo', 'timestamp' ) ) ) {
+ $row = $this->claimOldest( $uuid );
+ } else { // random first
+ $rand = mt_rand( 0, self::MAX_JOB_RANDOM ); // encourage concurrent UPDATEs
+ $gte = (bool)mt_rand( 0, 1 ); // find rows with rand before/after $rand
+ $row = $this->claimRandom( $uuid, $rand, $gte );
+ }
+ // Check if we found a row to reserve...
+ if ( !$row ) {
+ $this->cache->set( $this->getCacheKey( 'empty' ), 'true', self::CACHE_TTL_LONG );
+ break; // nothing to do
+ }
+ JobQueue::incrStats( 'job-pop', $this->type );
+ // Get the job object from the row...
+ $title = Title::makeTitleSafe( $row->job_namespace, $row->job_title );
+ if ( !$title ) {
+ $dbw->delete( 'job', array( 'job_id' => $row->job_id ), __METHOD__ );
+ wfDebug( "Row has invalid title '{$row->job_title}'." );
+ continue; // try again
+ }
+ $job = Job::factory( $row->job_cmd, $title,
+ self::extractBlob( $row->job_params ), $row->job_id );
+ $job->metadata['id'] = $row->job_id;
+ $job->id = $row->job_id; // XXX: work around broken subclasses
+ break; // done
+ } while ( true );
+ } catch ( DBError $e ) {
+ $this->throwDBException( $e );
+ }