django-atomic-celery 1.1.2

Don’t Use This Library

This library uses django-atomic-signals. Unfortunately this is not a great way of achieving “don’t run this code until the transaction commits” any more. There is plenty of extra description on django-atomic-signals’ README, and also on the similar library django-transaction-signals, by Django core developer Aymeric.

If you want a supported method of executing a celery task on commit, then:

• on Django >= 1.9, use the built-in on_commit hook

• on Django < 1.9, use django-transaction-hooks (the original source of 1.9’s on_commit)

Both give examples with celery tasks so you are in good hands.

If your project is still using this library, please migrate. You will need to remove django-atomic-signals as well as django-atomic-celery. A new, “don’t use me” version that breaks on import will be pushed soon to PyPI to propagate this warning.

Old Readme Continues

django_atomic_celery provides a Django 1.6-1.7 compatible approach to transactionally aware Celery task scheduling.

To install django_atomic_celery, do yourself a favor and don’t use anything other than pip:

$ pip install django-atomic-celery

Add django_atomic_celery along with its dependency, django_atomic_signals, to the list of installed apps in your settings file:

INSTALLED_APPS = (
    'django_atomic_signals',
    'django_atomic_celery',
    ..
)

Usage

Using django_atomic_celery is exactly like using Celery the way you normally would. However, instead of importing Celery’s variant of the task decorator, import it from django_atomic_celery:

from django_atomic_celery import task


@task
def simple_task():
    ..


@task(ignore_result=True, max_retries=3, default_retry_delay=10)
def retrying_task(arg):
    ..

If you use Celery 3.1 and its internal integration of Django, you can choose to instantiate your Celery app providing the atomic task class as the task_cls argument to have all tasks be atomic transaction aware. Based on an example from the Celery documentation this is done as follows:

from celery import Celery

..
app = Celery('proj', task_cls='django_atomic_celery:PostTransactionTask')
..