mirror of
https://github.com/django-q2/django-q2.git
synced 2026-09-21 22:58:11 +08:00
bca22054df25c9eea4ead88667fc0a74dd092922
According to multiprocessing documentation for Value (https://docs.python.org/3/library/multiprocessing.html#multiprocessing.Value) reads and writes are protected with lock when the lock argument is True (the default) or the lock argument is an instance of Lock or RLock. The documentation states that operations like += are not atomic as that involves reading and writing. On the worker side the critical section includes also storing finished task result because the timeout could happen after the task function has finished but before the result has been stored and timer.value has been updated to tell the guard process that the task has been finished. On the guard side the critical section includes all checks done to see if the worker has timed out or died and the actual reincarnation function because the worker could update timer value to -1 (idle) or -2 (recycle) after the guard has seen timer value 0 (timeout) and is going to terminate the worker.
.. image:: docs/_static/logo.png
:align: center
:alt: Q logo
:target: https://django-q.readthedocs.org/
A multiprocessing distributed task queue for Django
---------------------------------------------------
|image0| |image1| |docs| |image2|
Features
~~~~~~~~
- Multiprocessing worker pool
- Asynchronous tasks
- Scheduled and repeated tasks
- Encrypted and compressed packages
- Failure and success database or cache
- Result hooks, groups and chains
- Django Admin integration
- PaaS compatible with multiple instances
- Multi cluster monitor
- Redis, Disque, IronMQ, SQS, MongoDB or ORM
- Rollbar and Sentry support
Requirements
~~~~~~~~~~~~
- `Django <https://www.djangoproject.com>`__ > = 1.11.11
- `Django-picklefield <https://github.com/gintas/django-picklefield>`__
- `Arrow <https://github.com/crsmithdev/arrow>`__
- `Blessed <https://github.com/jquast/blessed>`__
Tested with: Python 3.6. 3.7 Django 1.11.x and 2.1.x
.. warning:: Since Python 3.7 `async` became a reserved keyword and was refactored to `async_task`
Brokers
~~~~~~~
- `Redis <https://django-q.readthedocs.org/en/latest/brokers.html#redis>`__
- `Disque <https://django-q.readthedocs.org/en/latest/brokers.html#disque>`__
- `IronMQ <https://django-q.readthedocs.org/en/latest/brokers.html#ironmq>`__
- `Amazon SQS <https://django-q.readthedocs.org/en/latest/brokers.html#amazon-sqs>`__
- `MongoDB <https://django-q.readthedocs.org/en/latest/brokers.html#mongodb>`__
- `Django ORM <https://django-q.readthedocs.org/en/latest/brokers.html#django-orm>`__
Installation
~~~~~~~~~~~~
- Install the latest version with pip::
$ pip install django-q
- Add `django_q` to your `INSTALLED_APPS` in your projects `settings.py`::
INSTALLED_APPS = (
# other apps
'django_q',
)
- Run Django migrations to create the database tables::
$ python manage.py migrate
- Choose a message `broker <https://django-q.readthedocs.org/en/latest/brokers.html>`__ , configure and install the appropriate client library.
Read the full documentation at `https://django-q.readthedocs.org <https://django-q.readthedocs.org>`__
Configuration
~~~~~~~~~~~~~
All configuration settings are optional. e.g:
.. code:: python
# settings.py example
Q_CLUSTER = {
'name': 'myproject',
'workers': 8,
'recycle': 500,
'timeout': 60,
'compress': True,
'cpu_affinity': 1,
'save_limit': 250,
'queue_limit': 500,
'label': 'Django Q',
'redis': {
'host': '127.0.0.1',
'port': 6379,
'db': 0, }
}
For full configuration options, see the `configuration documentation <https://django-q.readthedocs.org/en/latest/configure.html>`__.
Management Commands
~~~~~~~~~~~~~~~~~~~
Start a cluster with::
$ python manage.py qcluster
Monitor your clusters with::
$ python manage.py qmonitor
Check overall statistics with::
$ python manage.py qinfo
Creating Tasks
~~~~~~~~~~~~~~
Use `async_task` from your code to quickly offload tasks:
.. code:: python
from django_q.tasks import async_task, result
# create the task
async_task('math.copysign', 2, -2)
# or with a reference
import math.copysign
task_id = async_task(copysign, 2, -2)
# get the result
task_result = result(task_id)
# result returns None if the task has not been executed yet
# you can wait for it
task_result = result(task_id, 200)
# but in most cases you will want to use a hook:
async_task('math.modf', 2.5, hook='hooks.print_result')
# hooks.py
def print_result(task):
print(task.result)
For more info see `Tasks <https://django-q.readthedocs.org/en/latest/tasks.html>`__
Schedule
~~~~~~~~
Schedules are regular Django models. You can manage them through the
Admin page or directly from your code:
.. code:: python
# Use the schedule function
from django_q.tasks import schedule
schedule('math.copysign',
2, -2,
hook='hooks.print_result',
schedule_type=Schedule.DAILY)
# Or create the object directly
from django_q.models import Schedule
Schedule.objects.create(func='math.copysign',
hook='hooks.print_result',
args='2,-2',
schedule_type=Schedule.DAILY
)
# Run a task every 5 minutes, starting at 6 today
# for 2 hours
import arrow
schedule('math.hypot',
3, 4,
schedule_type=Schedule.MINUTES,
minutes=5,
repeats=24,
next_run=arrow.utcnow().replace(hour=18, minute=0))
For more info check the `Schedules <https://django-q.readthedocs.org/en/latest/schedules.html>`__ documentation.
Testing
~~~~~~~
To run the tests you will need the following in addition to install requirements:
* `py.test <http://pytest.org/latest/>`__
* `pytest-django <https://github.com/pytest-dev/pytest-django>`__
* disque from https://github.com/antirez/disque.git
* Redis
* MongoDB
The following commands can be used to run the tests:
```
# Create virtual environment
python -m venv venv
# Install requirements
venv/bin/pip install -r requirements.txt
# Install test dependencies
venv/bin/pip install pytest pytest-django
# Install django-q
venv/bin/python setup.py develop
# Run required services (you need to have docker-compose installed)
docker-compose -f test-services-docker-compose.yaml up -d
# Run tests
venv/bin/pytest
# Stop the services required by tests (when you no longer plan to run tests)
docker-compose -f test-services-docker-compose.yaml down
```
Locale
~~~~~~
Currently available in English and French.
Translation pull requests are always welcome.
Todo
~~~~
- Better tests and coverage
- Less dependencies?
Acknowledgements
~~~~~~~~~~~~~~~~
- Django Q was inspired by working with
`Django-RQ <https://github.com/ui/django-rq>`__ and
`RQ <https://github.com/ui/django-rq>`__
- Human readable hashes by
`HumanHash <https://github.com/zacharyvoase/humanhash>`__
- Redditors feedback at `r/django <https://www.reddit.com/r/django/>`__
.. |image0| image:: https://travis-ci.org/Koed00/django-q.svg?branch=master
:target: https://travis-ci.org/Koed00/django-q
.. |image1| image:: http://codecov.io/github/Koed00/django-q/coverage.svg?branch=master
:target: http://codecov.io/github/Koed00/django-q?branch=master
.. |image2| image:: http://badges.gitter.im/Join%20Chat.svg
:target: https://gitter.im/Koed00/django-q
.. |docs| image:: https://readthedocs.org/projects/docs/badge/?version=latest
:alt: Documentation Status
:scale: 100
:target: https://django-q.readthedocs.org/
Languages
Python
99.5%
Makefile
0.4%