(bug 37072) - prevents infinite job loop

nextJob.php does not honor jobs types being excluded from the default
job queue by using $wgJobTypesExcludedFromDefaultQueue. Since those jobs
can never get processed, nextJob.php will always return a database which
might produce a nasty infinite loop while trying to process the whole
queue.

Job::pop did take in account wgJobTypesExcludedFromDefaultQueue to
filter the jobs out. So this patch factor out the code in a new method
and uses it for nextJob.php.

Change-Id: I15197ffcca00f229c9004e2abd87e009bc40f384

diff --git a/includes/job/JobQueue.php b/includes/job/JobQueue.php
index 0065247..a3493b4 100644 (file)
--- a/includes/job/JobQueue.php
+++ b/includes/job/JobQueue.php
@@ -113,7 +113,6 @@ abstract class Job {
         * @return Job or false if there's no jobs
         */
        static function pop( $offset = 0 ) {
-               global $wgJobTypesExcludedFromDefaultQueue;
                wfProfileIn( __METHOD__ );
 
                $dbr = wfGetDB( DB_SLAVE );
@@ -124,12 +123,9 @@ abstract class Job {
                        NB: If random fetch previously was used, offset
                                will always be ahead of few entries
                */
-               $conditions = array();
-               if ( count( $wgJobTypesExcludedFromDefaultQueue ) != 0 ) {
-                       foreach ( $wgJobTypesExcludedFromDefaultQueue as $cmdType ) {
-                               $conditions[] = "job_cmd != " . $dbr->addQuotes( $cmdType );
-                       }
-               }
+
+               $conditions = self::defaultQueueConditions();
+
                $offset = intval( $offset );
                $options = array( 'ORDER BY' => 'job_id', 'USE INDEX' => 'PRIMARY' );
 
@@ -318,6 +314,26 @@ abstract class Job {
                wfIncrStats( 'job-insert', count( $jobs ) );
        }
 
+
+       /**
+        * SQL conditions to apply on most JobQueue queries
+        *
+        * Whenever we exclude jobs types from the default queue, we want to make
+        * sure that queries to the job queue actually ignore them.
+        *
+        * @return array SQL conditions suitable for Database:: methods
+        */
+       static function defaultQueueConditions( ) {
+               global $wgJobTypesExcludedFromDefaultQueue;
+               $conditions = array();
+               if ( count( $wgJobTypesExcludedFromDefaultQueue ) > 0 ) {
+                       foreach ( $wgJobTypesExcludedFromDefaultQueue as $cmdType ) {
+                               $conditions[] = "job_cmd != " . $dbr->addQuotes( $cmdType );
+                       }
+               }
+               return $conditions;
+       }
+
        /*-------------------------------------------------------------------------
         * Non-static functions
         *------------------------------------------------------------------------*/

diff --git a/maintenance/nextJobDB.php b/maintenance/nextJobDB.php
index 67aa308..d9bd3b8 100644 (file)
--- a/maintenance/nextJobDB.php
+++ b/maintenance/nextJobDB.php
@@ -94,11 +94,12 @@ class nextJobDB extends Maintenance {
                $lb = wfGetLB( $dbName );
                $db = $lb->getConnection( DB_MASTER, array(), $dbName );
                if ( $type === false ) {
-                       $conds = array();
+                       $conds = JobQueue::defaultQueueConditions( );
                } else {
                        $conds = array( 'job_cmd' => $type );
                }
 
+
                $exists = (bool) $db->selectField( 'job', '1', $conds, __METHOD__ );
                $lb->reuseConnection( $db );
                return $exists;