mirror of
https://github.com/hanzoai/tasks.git
synced 2026-10-04 02:04:03 +00:00
Prathyush PVandGitHub
d98eb745ad
<!-- Describe what has changed in this PR --> **What changed?** Adding FOR UPDATE clause when fetching queueV2 metadata and removing unused field version from queue metadata. <!-- Tell your future self why have you made these changes --> **Why?** If a queueV2 metadata row is fetched in a transaction, we have to place a lock on that row to avoid another transaction reading from that line. This can happen when two threads are trying to delete messages from the queue. Two of them will update queue metadata and write it back. This will lead to a race condition. By adding 'FOR UPDATE' SQL clause, the first transaction will get an exclusive lock on the row. The second transaction will wait until the first transaction is complete or rollback. Also, removing the version field from QueueV2 metadata table. We will not be using this field since we are using sql transactions. <!-- How have you verified this change? Tested locally? Added a unit test? Checked in staging env? --> **How did you test it?** Unit test. Executed through the debugger to make sure SelectFromQueueV2MetadataForUpdate() is called instead of SelectFromQueueV2Metadata() when executed inside a trancation. <!-- Assuming the worst case, what can be broken when deploying this change to production? --> **Potential risks** <!-- Is this PR a hotfix candidate or require that a notification be sent to the broader community? (Yes/No) --> **Is hotfix candidate?**