Publish and Subscribe with Celery
Python | Celery 3 | Celery 4 | Celery 5 |
---|---|---|---|
3.7 | |||
3.8 | |||
3.9 | |||
3.10 | |||
3.11 | |||
3.12 | |||
pypy 3.9 | |||
pypy 3.10 |
import celery
import celery_pubsub
@celery.shared_task
def my_task_1(*args, **kwargs):
return "task 1 done"
@celery.shared_task
def my_task_2(*args, **kwargs):
return "task 2 done"
# First, let's subscribe
celery_pubsub.subscribe('some.topic', my_task_1)
celery_pubsub.subscribe('some.topic', my_task_2)
# Or subscribe with decorator + task decorator
@celery_pubsub.subscribe_to(topic="some.topic")
@celery.shared_task
def my_task_3(*args, **kwargs):
return "task 3 done"
# Or use only `subscribe_to` decorator
@celery_pubsub.subscribe_to(topic="some.topic")
def my_task_4(*args, **kwargs):
return "task 4 done"
# Now, let's publish something
res = celery_pubsub.publish('some.topic', data='something', value=42)
# We can get the results if we want to (and if the tasks returned something)
# But in pub/sub, usually, there's no result.
print(res.get())
# This will get nowhere, as no task subscribed to this topic
res = celery_pubsub.publish('nowhere', data='something else', value=23)
Wildcards can be used in topic names:
-
*
matches any one groupsome.*.test
will matchsome.awesome.test
,some.random.test
but notsome.pretty.cool.test
,elsewhere
orhere.some.up.test
some.*
will matchsome.test
andsome.thing
but it won't matchsome
orsome.testy.test
-
#
matches any number of groupssome.#.test
will matchsome.awesome.test
,some.random.test
,some.pretty.cool.test
but notelsewhere
orhere.some.up.test
some.#
will match anything that starts withsome.
, such assome.very.specific.topic.indeed
#
will match anything
# Let's subscribe
celery_pubsub.subscribe('some.*', my_task_1)
celery_pubsub.subscribe('some.*.test', my_task_2)
celery_pubsub.subscribe('some.#', my_task_3)
celery_pubsub.subscribe('#', my_task_4)
celery_pubsub.subscribe('some.beep', my_task_5)
# it's okay to have more than one task on the same topic
celery_pubsub.subscribe('some.beep', my_task_6)
# or subscribe directly with decorator
@celery_pubsub.subscribe_to(topic="some.*")
def my_task_7(*args, **kwargs): ...
@celery_pubsub.subscribe_to(topic="some.*.test")
def my_task_8(*args, **kwargs): ...
# Let's publish
celery_pubsub.publish('nowhere', 4) # task 4 only
celery_pubsub.publish('some', 8) # task 4 only
celery_pubsub.publish('some.thing', 15) # tasks 1, 3, 4 and 7
celery_pubsub.publish('some.true.test', 16) # tasks 2, 3, 4 and 8
celery_pubsub.publish('some.beep', 23) # tasks 1, 3, 4, 5, 6 and 7
celery_pubsub.publish('some.very.good.test', 42) # tasks 3 and 4
# And if you want to publish synchronously:
celery_pubsub.publish_now('some.very.good.test', 42) # tasks 3 and 4
# You can unsubscribe too
celery_pubsub.unsubscribe('#', my_task_4)
# Now, task 4 will not be called anymore
celery_pubsub.publish('some.very.good.test', 42) # task 3 only
- 2.0.0
- Add new decorator: subscribe_to
- Drop support for CPython 2.7, 3.4, 3.5, 3.6
- Drop support for Pypy 2.7 and 3.6.
- Drop support for Celery 3.
- Add support for Pypy 3.9 and 3.10.
- Add support for CPython 3.11 and 3.12.
- Type hints are now directly in the code. No more stubs files.
- 1.0.2
- Add stubs file for type hinting.
- 1.0.1
- Changed
README.rst
toREADME.md
. - Added better badges to show the supported status for each Celery & Python version.
- Changed
- 1.0.0
- Flexible requirements (no more pinned). Better to support a wide range of environments.
- Changed test framework from nose to pytest.
- Flake8
- Support for Python 3.9 and 3.10.
- 0.2.1
- Performance: Internally uses a
set
to store the subscribed tasks. - Updated Codeclimate as the
old reporter <https://github.com/codeclimate/python-test-reporter>
_ is deprecated. - Pinned requirements' dependency versions.
- celery 4.3.0 -> 4.4.0
- kombu 4.6.4 -> 4.6.7
- billiard 3.6.1.0 -> 3.6.2.0
- codeclimate-test-reporter 0.2.3 -> removed!
- Performance: Internally uses a
- 0.2.0
- Removed Python 3.4 support. Reason: no longer supported by Kombu 4.6+.
- Officially supported by Python 3.8.
- Pinned requirements' dependency versions.
- celery 4.2.1 -> 4.3.0
- kombu 4.2.1 -> 4.6.4
- billiard 3.5.0.4 -> 3.6.1.0
- vine 1.1.4 -> 1.3.0
- 0.1.9
- Added Python 3.4, 3.5, 3.7, and multiple branches of pypy
- Pinned requirements' dependency versions.
- celery 4.1.0 -> 4.2.1
- kombu 4.1.0 -> 4.2.1
- billiard 3.5.0 -> 3.5.0.4
- nose pinned to 1.3.7
- coverage pinned to 4.3.4 (was already 4.3.4 but fuzzy)
- codeclimate-test-reported pinned to 0.2.3
- Extra badge to show the number of downloads (thanks to PePy)
- 0.1.8
- Fixup for broken
pip install celery_pubsub==0.1.7
- Fixup for broken
- 0.1.7
- PyPI long description fixed
- Removed README.md and fixed README.rst
- Added command
python setup.py test
to run unit tests with coverage - pypy support
- 0.1.5
- Python 3 support
- 0.1.1
- Added README
- Refined setup
- No need to access celery_pubsub.pubsub anymore. Direct access in celery_pubsub.
- Tests moved out of package
- Added Travis for CI
- 0.1
- Initial version