============================================
crunchy - Distributed Task Queue for Django.
============================================
:Authors:
Ask Solem (askh@opera.com)
:Version: 0.1.0
Introduction
------------
``crunchy`` is a distributed task queue framework for Django.
More information will follow.
Installation
=============
You can install ``crunchy`` either via the Python Package Index (PyPI)
or from source.
To install using ``pip``,::
$ pip install crunchy
To install using ``easy_install``,::
$ easy_install crunchy
If you have downloaded a source tarball you can install it
by doing the following,::
$ python setup.py build
# python setup.py install # as root
Usage
=====
Have to write a cool tutorial, but here is some simple usage info.
*Note* You need to have a AMQP message broker running, like `RabbitMQ`_,
and you need to have the amqp server setup in your settings file, as described
in the `carrot distribution README`_.
*Note* If you're running ``SQLite`` as the database backend, ``crunchd`` will
only be able to process one message at a time, this because ``SQLite`` doesn't
allow concurrent writes.
.. _`RabbitMQ`: http://www.rabbitmq.com
.. _`carrot distribution README`: http://pypi.python.org/pypi/carrot/0.3.3
Defining tasks
--------------
>>> from crunchy.task import tasks
>>> from crunchy.log import setup_logger
>>> def do_something(some_arg, **kwargs):
... logger = setup_logger(**kwargs)
... logger.info("Did something: %s" % some_arg)
>>> task.register(do_something, "do_something")
*Note* Task functions only supports keyword arguments.
Tell the crunch daemon to run a task
-------------------------------------
>>> from crunchy.task import delay_task
>>> delay_task("do_something", some_arg="foo bar baz")
Running the crunch daemon
--------------------------
::
$ cd mydjangoproject
$ env DJANGO_SETTINGS_MODULE=settings crunchd
[....]
[2009-04-23 17:44:05,115: INFO/Process-1] Did something: foo bar baz
[2009-04-23 17:44:05,118: INFO/MainProcess] Waiting for queue.
Autodiscovery of tasks
-----------------------
``crunchy`` has an autodiscovery feature like the Django Admin, that
automatically loads any ``tasks.py`` module in the applications listed
in ``settings.INSTALLED_APPS``.
A good place to add this command could be in your ``urls.py``,
::
from crunchy.task import tasks
tasks.autodiscover()
Then you can add new tasks in your applications ``tasks.py`` module,
::
from crunchy.task import tasks
from crunchy.log import setup_logger
from clickcounter.models import ClickCount
def increment_click(for_url, **kwargs):
logger = setup_logger(**kwargs)
clicks_for_url, cr = ClickCount.objects.get_or_create(url=for_url)
clicks_for_url.clicks = clicks_for_url.clicks + 1
clicks_for_url.save()
logger.info("Incremented click count for %s (not at %d)" % (
for_url, clicks_for_url.clicks)
tasks.register(increment_click, "increment_click")
License
=======
This software is licensed under the ``New BSD License``. See the ``LICENSE``
file in the top distribution directory for the full license text.
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