django-rq 1.2.0

An app that provides django integration for RQ (Redis Queue)

=========
Django-RQ
=========

|Build Status|

Django integration with `RQ <https://github.com/nvie/rq>`__, a `Redis <http://redis.io/>`__
based Python queuing library. `Django-RQ <https://github.com/rq/django-rq>`__ is a
simple app that allows you to configure your queues in django's ``settings.py``
and easily use them in your project.

============
Requirements
============

* `Django <https://www.djangoproject.com/>`__ (1.8+)
* `RQ <https://github.com/nvie/rq>`__

============
Installation
============

* Install ``django-rq`` (or `download from PyPI <http://pypi.python.org/pypi/django-rq>`__):

.. code-block:: python

pip install django-rq

* Add ``django_rq`` to ``INSTALLED_APPS`` in ``settings.py``:

.. code-block:: python

INSTALLED_APPS = (
# other apps
"django_rq",
)

* Configure your queues in django's ``settings.py`` (syntax based on Django's database config):

.. code-block:: python

RQ_QUEUES = {
'default': {
'HOST': 'localhost',
'PORT': 6379,
'DB': 0,
'PASSWORD': 'some-password',
'DEFAULT_TIMEOUT': 360,
},
'with-sentinel': {
'SENTINELS': [('localhost', 26736), ('localhost', 26737)],
'MASTER_NAME': 'redismaster',
'DB': 0,
'PASSWORD': 'secret',
'SOCKET_TIMEOUT': None,
},
'high': {
'URL': os.getenv('REDISTOGO_URL', 'redis://localhost:6379/0'), # If you're on Heroku
'DEFAULT_TIMEOUT': 500,
},
'low': {
'HOST': 'localhost',
'PORT': 6379,
'DB': 0,
}
}

RQ_EXCEPTION_HANDLERS = ['path.to.my.handler'] # If you need custom exception handlers

* Include ``django_rq.urls`` in your ``urls.py``:

.. code-block:: python

# For Django < 2.0
urlpatterns += [
url(r'^django-rq/', include('django_rq.urls')),
]

# For Django >= 2.0
urlpatterns += [
path('django-rq/', include('django_rq.urls'))
]

=====
Usage
=====

Putting jobs in the queue
-------------------------

`Django-RQ` allows you to easily put jobs into any of the queues defined in
``settings.py``. It comes with a few utility functions:

* ``enqueue`` - push a job to the ``default`` queue:

.. code-block:: python

import django_rq
django_rq.enqueue(func, foo, bar=baz)

* ``get_queue`` - returns an ``Queue`` instance.

.. code-block:: python

import django_rq
queue = django_rq.get_queue('high')
queue.enqueue(func, foo, bar=baz)

In addition to ``name`` argument, ``get_queue`` also accepts ``default_timeout``,
``is_async``, ``autocommit`` and ``queue_class`` arguments. For example:

.. code-block:: python

queue = django_rq.get_queue('default', autocommit=True, is_async=True, default_timeout=360)
queue.enqueue(func, foo, bar=baz)

* ``get_connection`` - accepts a single queue name argument (defaults to "default")
and returns a connection to the queue's `Redis`_ server:

.. code-block:: python

import django_rq
redis_conn = django_rq.get_connection('high')

* ``get_worker`` - accepts optional queue names and returns a new `RQ`
``Worker`` instance for specified queues (or ``default`` queue):

.. code-block:: python

import django_rq
worker = django_rq.get_worker() # Returns a worker for "default" queue
worker.work()
worker = django_rq.get_worker('low', 'high') # Returns a worker for "low" and "high"


@job decorator
--------------

To easily turn a callable into an RQ task, you can also use the ``@job``
decorator that comes with ``django_rq``:

.. code-block:: python

from django_rq import job

@job
def long_running_func():
pass
long_running_func.delay() # Enqueue function in "default" queue

@job('high')
def long_running_func():
pass
long_running_func.delay() # Enqueue function in "high" queue

It's possible to specify default for ``result_ttl`` decorator keyword argument
via ``DEFAULT_RESULT_TTL`` setting:

.. code-block:: python

RQ = {
'DEFAULT_RESULT_TTL': 5000,
}

With this setting, job decorator will set ``result_ttl`` to 5000 unless it's
specified explicitly.


Running workers
---------------
django_rq provides a management command that starts a worker for every queue
specified as arguments::

python manage.py rqworker high default low

If you want to run ``rqworker`` in burst mode, you can pass in the ``--burst`` flag::

python manage.py rqworker high default low --burst

If you need to use custom worker, job or queue classes, it is best to use global settings
(see `Custom queue classes`_ and `Custom job and worker classes`_). However, it is also possible
to override such settings with command line options as follows.

To use a custom worker class, you can pass in the ``--worker-class`` flag
with the path to your worker::

python manage.py rqworker high default low --worker-class 'path.to.GeventWorker'

To use a custom queue class, you can pass in the ``--queue-class`` flag
with the path to your queue class::

python manage.py rqworker high default low --queue-class 'path.to.CustomQueue'

To use a custom job class, provide ``--job-class`` flag.

Support for RQ Scheduler
------------------------

If you have `RQ Scheduler <https://github.com/ui/rq-scheduler>`__ installed,
you can also use the ``get_scheduler`` function to return a ``Scheduler``
instance for queues defined in settings.py's ``RQ_QUEUES``. For example:

.. code-block:: python

import django_rq
scheduler = django_rq.get_scheduler('default')
job = scheduler.enqueue_at(datetime(2020, 10, 10), func)

You can also use the management command ``rqscheduler`` to start the scheduler::

python manage.py rqscheduler

Support for django-redis and django-redis-cache
-----------------------------------------------

If you have `django-redis <https://django-redis.readthedocs.org/>`__ or
`django-redis-cache <https://github.com/sebleier/django-redis-cache/>`__
installed, you can instruct django_rq to use the same connection information
from your Redis cache. This has two advantages: it's DRY and it takes advantage
of any optimization that may be going on in your cache setup (like using
connection pooling or `Hiredis <https://github.com/redis/hiredis>`__.)

To use configure it, use a dict with the key ``USE_REDIS_CACHE`` pointing to the
name of the desired cache in your ``RQ_QUEUES`` dict. It goes without saying
that the chosen cache must exist and use the Redis backend. See your respective
Redis cache package docs for configuration instructions. It's also important to
point out that since the django-redis-cache ``ShardedClient`` splits the cache
over multiple Redis connections, it does not work.

Here is an example settings fragment for `django-redis`:

.. code-block:: python

CACHES = {
'redis-cache': {
'BACKEND': 'redis_cache.cache.RedisCache',
'LOCATION': 'localhost:6379:1',
'OPTIONS': {
'CLIENT_CLASS': 'django_redis.client.DefaultClient',
'MAX_ENTRIES': 5000,
},
},
}

RQ_QUEUES = {
'high': {
'USE_REDIS_CACHE': 'redis-cache',
},
'low': {
'USE_REDIS_CACHE': 'redis-cache',
},
}

Queue Statistics
----------------

``django_rq`` also provides a dashboard to monitor the status of your queues at
``/django-rq/`` (or whatever URL you set in your ``urls.py`` during installation.

You can also add a link to this dashboard link in ``/admin`` by adding
``RQ_SHOW_ADMIN_LINK = True`` in ``settings.py``. Be careful though, this will
override the default admin template so it may interfere with other apps that
modifies the default admin template.

These statistics are also available in JSON format via
``/django-rq/stats.json``, which is accessible to staff members.
If you need to access this view via other
HTTP clients (for monitoring purposes), you can define ``RQ_API_TOKEN`` and access it via
``/django-rq/stats.json/<API_TOKEN>``.

.. image:: demo-django-rq-json-dashboard.png


Additionaly, these statistics are also accessible from the command line.

.. code-block:: bash

python manage.py rqstats
python manage.py rqstats --interval=1 # Refreshes every second
python manage.py rqstats --json # Output as JSON
python manage.py rqstats --yaml # Output as YAML

.. image:: demo-django-rq-cli-dashboard.gif

Configuring Sentry
-------------------
The ``SENTRY_DSN`` value from ``settings.py`` is used by default:

``SENTRY_DSN = 'https://*****@sentry.io/222222'``

Also you can specify ``sentry-dsn`` parameter when running rqworker:

``./manage.py rqworker --sentry-dsn=https://*****@sentry.io/222222``

Configuring Logging
-------------------

Starting from version 0.3.3, RQ uses Python's ``logging``, this means
you can easily configure ``rqworker``'s logging mechanism in django's
``settings.py``. For example:

.. code-block:: python

LOGGING = {
"version": 1,
"disable_existing_loggers": False,
"formatters": {
"rq_console": {
"format": "%(asctime)s %(message)s",
"datefmt": "%H:%M:%S",
},
},
"handlers": {
"rq_console": {
"level": "DEBUG",
"class": "rq.utils.ColorizingStreamHandler",
"formatter": "rq_console",
"exclude": ["%(asctime)s"],
},
# If you use sentry for logging
'sentry': {
'level': 'ERROR',
'class': 'raven.contrib.django.handlers.SentryHandler',
},
},
'loggers': {
"rq.worker": {
"handlers": ["rq_console", "sentry"],
"level": "DEBUG"
},
}
}

Note: error logging to Sentry is known to be unreliable with RQ when using async
transports (the default transport). Please configure ``Raven`` to use
``sync+https://`` or ``requests+https://`` transport in ``settings.py``:

.. code-block:: python

RAVEN_CONFIG = {
'dsn': 'sync+https://public:[e-mail]/1',
}

For more info, refer to `Raven's documentation <http://raven.readthedocs.org/>`__.

Custom Queue Classes
--------------------

By default, every queue will use ``DjangoRQ`` class. If you want to use a custom queue class, you can do so
by adding a ``QUEUE_CLASS`` option on a per queue basis in ``RQ_QUEUES``:

.. code-block:: python

RQ_QUEUES = {
'default': {
'HOST': 'localhost',
'PORT': 6379,
'DB': 0,
'QUEUE_CLASS': 'module.path.CustomClass',
}
}

or you can specify ``DjangoRQ`` to use a custom class for all your queues in ``RQ`` settings:

.. code-block:: python

RQ = {
'QUEUE_CLASS': 'module.path.CustomClass',
}

Custom queue classes should inherit from ``django_rq.queues.DjangoRQ``.

If you are using more than one queue class (not recommended), be sure to only run workers
on queues with same queue class. For example if you have two queues defined in ``RQ_QUEUES`` and
one has custom class specified, you would have to run at least two separate workers for each
queue.

Custom Job and Worker Classes
-----------------------------

Similarly to custom queue classes, global custom job and worker classes can be configured using
``JOB_CLASS`` and ``WORKER_CLASS`` settings:

.. code-block:: python

RQ = {
'JOB_CLASS': 'module.path.CustomJobClass',
'WORKER_CLASS': 'module.path.CustomWorkerClass',
}

Custom job class should inherit from ``rq.job.Job``. It will be used for all jobs
if configured.

Custom worker class should inherit from ``rq.worker.Worker``. It will be used for running
all workers unless overriden by ``rqworker`` management command ``worker-class`` option.

Testing Tip
-----------

For an easier testing process, you can run a worker synchronously this way:

.. code-block:: python

from django.test import TestCase
from django_rq import get_worker

class MyTest(TestCase):
def test_something_that_creates_jobs(self):
... # Stuff that init jobs.
get_worker().work(burst=True) # Processes all jobs then stop.
... # Asserts that the job stuff is done.

Synchronous Mode
----------------

You can set the option ``ASYNC`` to ``False`` to make synchronous operation the
default for a given queue. This will cause jobs to execute immediately and on
the same thread as they are dispatched, which is useful for testing and
debugging. For example, you might add the following after you queue
configuration in your settings file:

.. code-block:: python

# ... Logic to set DEBUG and TESTING settings to True or False ...

# ... Regular RQ_QUEUES setup code ...

if DEBUG or TESTING:
for queueConfig in RQ_QUEUES.itervalues():
queueConfig['ASYNC'] = False

Note that setting the ``is_async`` parameter explicitly when calling ``get_queue``
will override this setting.

=============
Running Tests
=============

To run ``django_rq``'s test suite::

`which django-admin.py` test django_rq --settings=django_rq.tests.settings --pythonpath=.

===================
Deploying on Ubuntu
===================

Create an rqworker service that runs the high, default, and low queues.

sudo vi /etc/systemd/system/rqworker.service

.. code-block:: bash

[Unit]
Description=Django-RQ Worker
After=network.target

[Service]
WorkingDirectory=<<path_to_your_project_folder>>
ExecStart=/home/ubuntu/.virtualenv/<<your_virtualenv>>/bin/python \
<<path_to_your_project_folder>>/manage.py \
rqworker high default low

[Install]
WantedBy=multi-user.target

Enable and start the sevice

.. code-block:: bash

sudo systemctl enable rqworker
sudo systemctl start rqworker

===================
Deploying on Heroku
===================

Add `django-rq` to your `requirements.txt` file with:

.. code-block:: bash

pip freeze > requirements.txt

Update your `Procfile` to:

.. code-block:: bash

web: gunicorn --pythonpath="$PWD/your_app_name" config.wsgi:application

worker: python your_app_name/manage.py rqworker high default low

Commit and re-deploy. Then add your new worker with:

.. code-block:: bash

heroku scale worker=1

=======================
Django Suit Integration
=======================

You can use `django-suit-rq <https://github.com/gsmke/django-suit-rq>`__ to make your
admin fit in with the django-suit styles.

=========
Changelog
=========

See `changelog <https://github.com/rq/django-rq/blob/master/CHANGELOG.md>`.


.. |Build Status| image:: https://secure.travis-ci.org/rq/django-rq.svg?branch=master
:target: https://travis-ci.org/rq/django-rq