[gr8man]

Description

QueueJobModel::popWithLock() reserves a job inside a transaction, but the transaction was not closed on every code path, and a successful reservation was never verified.

1. Transaction leak. When the SELECT failed, the method returned null without calling transComplete(). The transaction depth stayed unbalanced, so a later transComplete() from an unrelated (nested) operation could commit or roll back work it did not own, and the connection remained inside an open transaction.
2. Unconfirmed reservations. The result of the UPDATE that changes the job status to RESERVED was discarded. A job could therefore be returned to the worker (and processed) even though the status was never actually persisted, which allows two workers to process the same job.

Changes

• src/Models/QueueJobModel.php
  • Wrapped the reservation in try { ... } finally { $this->db->transComplete(); } so the transaction is always closed, whichever path is taken.
  • The reservation is now confirmed with update() !== false && $this->db->affectedRows() === 1. When the reservation cannot be confirmed, the transaction is rolled back and null is returned, so the job stays PENDING and is never processed.
  • An empty result set (no pending job available) returns null before the update.

Testing

Added three cases to tests/Models/QueueJobModelTest.php:

• testPopWithLockReturnsNullAndClosesTransactionWhenQueryFails() — after a failed query, transDepth is back to 0.
• testPopWithLockRollsBackAndReturnsNullWhenUpdateFails() — when update() returns false, the method returns null, rolls back, and the row remains PENDING.
• testPopWithLockRollsBackAndReturnsNullWhenAffectedRowsIsNotOne() — when the update affects no rows, the same rollback and PENDING state are asserted.

Verified locally on PHP 8.5 with PHPUnit 11.5:

phpunit ....... OK (233 tests, 655 assertions, 27 skipped)
phpstan ....... [OK] No errors
psalm ......... No errors found
php-cs-fixer .. 0 of 75 files would be fixed