Python 3.13

Shut Down asyncio Worker Queues Cleanly

Asynchronous worker pools often start with a simple pattern: producers put jobs into an asyncio.Queue, consumers loop over get(), and the application waits for join() before exiting. The awkward part is shutdown. Older designs commonly put one sentinel value into the queue for each worker, cancel consumers after join(), or maintain a separate stop event. Each approach can work, but each adds a second protocol beside the queue itself. Python 3.13 added asyncio.Queue.shutdown() and the asyncio.QueueShutDown exception. They let the queue represent its own lifecycle: open for producers, shutting down while existing work drains, and finally closed to consumers.