pipeline.extern.logutils.queue

This module contains classes which help you work with queues. A typical application is when you want to log from performance-critical threads, but where the handlers you want to use are slow (for example, SMTPHandler). In that case, you can create a queue, pass it to a QueueHandler instance and use that instance with your loggers. Elsewhere, you can instantiate a QueueListener with the same queue and some slow handlers, and call start() on it. This will start monitoring the queue on a separate thread and call all the configured handlers on that thread, so that your logging thread is not held up by the slow handlers.

Note that as well as in-process queues, you can use these classes with queues from the multiprocessing module.

N.B. This is part of the standard library since Python 3.2, so the version here is for use with earlier Python versions.

Classes

QueueHandler(queue)	This handler sends events to a queue.
QueueListener(queue, *handlers)	This class implements an internal threaded listener which watches for LogRecords being added to a queue, removes them and passes them to a list of handlers for processing.