Shuts down the scheduler and immediately end all pending callbacks.
Parameter
Name
Description
await_msg_callbacks
bool
If True, the method will block until all currently executing callbacks are done processing. If False (default), the method will not wait for the currently running callbacks to complete.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-28 UTC."],[],[],null,["# Class Scheduler (2.31.0)\n\nVersion latestkeyboard_arrow_down\n\n- [2.31.0 (latest)](/python/docs/reference/pubsub/latest/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.30.0](/python/docs/reference/pubsub/2.30.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.29.1](/python/docs/reference/pubsub/2.29.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.28.0](/python/docs/reference/pubsub/2.28.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.27.3](/python/docs/reference/pubsub/2.27.3/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.26.1](/python/docs/reference/pubsub/2.26.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.25.2](/python/docs/reference/pubsub/2.25.2/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.23.1](/python/docs/reference/pubsub/2.23.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.22.0](/python/docs/reference/pubsub/2.22.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.21.5](/python/docs/reference/pubsub/2.21.5/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.20.3](/python/docs/reference/pubsub/2.20.3/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.19.8](/python/docs/reference/pubsub/2.19.8/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.18.4](/python/docs/reference/pubsub/2.18.4/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.17.1](/python/docs/reference/pubsub/2.17.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.16.1](/python/docs/reference/pubsub/2.16.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.15.2](/python/docs/reference/pubsub/2.15.2/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.14.1](/python/docs/reference/pubsub/2.14.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.13.12](/python/docs/reference/pubsub/2.13.12/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.12.1](/python/docs/reference/pubsub/2.12.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.11.1](/python/docs/reference/pubsub/2.11.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.10.0](/python/docs/reference/pubsub/2.10.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.9.0](/python/docs/reference/pubsub/2.9.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.8.0](/python/docs/reference/pubsub/2.8.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.7.1](/python/docs/reference/pubsub/2.7.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.6.1](/python/docs/reference/pubsub/2.6.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.5.0](/python/docs/reference/pubsub/2.5.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.4.2](/python/docs/reference/pubsub/2.4.2/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.3.0](/python/docs/reference/pubsub/2.3.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.2.0](/python/docs/reference/pubsub/2.2.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.1.0](/python/docs/reference/pubsub/2.1.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [2.0.0](/python/docs/reference/pubsub/2.0.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.7.2](/python/docs/reference/pubsub/1.7.2/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.6.1](/python/docs/reference/pubsub/1.6.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.5.0](/python/docs/reference/pubsub/1.5.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.4.3](/python/docs/reference/pubsub/1.4.3/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.3.1](/python/docs/reference/pubsub/1.3.1/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.2.0](/python/docs/reference/pubsub/1.2.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.1.0](/python/docs/reference/pubsub/1.1.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [1.0.2](/python/docs/reference/pubsub/1.0.2/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [0.45.0](/python/docs/reference/pubsub/0.45.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [0.44.0](/python/docs/reference/pubsub/0.44.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler)\n- [0.43.0](/python/docs/reference/pubsub/0.43.0/google.cloud.pubsub_v1.subscriber.scheduler.Scheduler) \n\n Scheduler()\n\nAbstract base class for schedulers.\n\nSchedulers are used to schedule callbacks asynchronously.\n\nProperties\n----------\n\n### queue\n\nQueue: A concurrency-safe queue specific to the underlying\nconcurrency implementation.\n\nThis queue is used to send messages *back* to the scheduling actor.\n\nMethods\n-------\n\n### schedule\n\n schedule(callback: typing.Callable, *args, **kwargs) -\u003e None\n\nSchedule the callback to be called asynchronously.\n\n### shutdown\n\n shutdown(\n await_msg_callbacks: bool = False,\n ) -\u003e typing.List[pubsub_v1.subscriber.message.Message]\n\nShuts down the scheduler and immediately end all pending callbacks."]]