Signals

Available signals

Django Q emits the following signals during its lifecycle.

Before enqueuing a task

The django_q.signals.pre_enqueue signal is emitted before a task is enqueued. The task dictionary is given as the task argument.

Before executing a task

The django_q.signals.pre_execute signal is emitted before a task is executed by a worker. This signal provides two arguments:

  • task: the task dictionary.
  • func: the actual function that will be executed. If the task was created with a function path, this argument will be the callable function nonetheless.

Subscribing to a signal

Connecting to a Django Q signal is done in the same manner as any other Django signal:

from django.dispatch import receiver
from django_q.signals import pre_enqueue, pre_execute

@receiver(pre_enqueue)
def my_pre_enqueue_callback(sender, task, **kwargs):
    print("Task {} will be enqueued".format(task["name"]))

@receiver(pre_execute)
def my_pre_execute_callback(sender, func, task, **kwargs):
    print("Task {} will be executed by calling {}".format(
          task["name"], func))