Python Shell Other
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Permalink
Failed to load latest commit information.
.github Adds Github pull request template Oct 24, 2016
celery Add task properties to AsyncResult, store in backend (#4490) Aug 17, 2018
docker Enable building docs in the Docker image (includes Sphinx version bum… May 11, 2018
docs Add task properties to AsyncResult, store in backend (#4490) Aug 17, 2018
examples Make __all__ immutable. (#4315) Oct 7, 2017
extra Adding the CMDS for Celery and Celery Beat to Run on Azure WebJob (#4484 Feb 3, 2018
requirements remove jython support (#4776) May 29, 2018
t Add task properties to AsyncResult, store in backend (#4490) Aug 17, 2018
.bumpversion.cfg Bump version: 4.2.0rc4 → 4.2.0 Jun 10, 2018
.cookiecutterrc Adds .cookiecutterrc Jul 6, 2016
.coveragerc Report coverage for all result backends. Oct 6, 2017
.editorconfig Updates, fixes, and improvements to documentation (#3976) Apr 15, 2017
.gitignore Fix grammar, update .gitignore (#3887) Mar 14, 2017
.landscape.yml flakes Oct 12, 2016
.travis.yml pypy2.7 6.0.0 (#4911) Jul 19, 2018
CONTRIBUTING.rst Add docker-compose and base dockerfile for development (#4482) Mar 18, 2018
CONTRIBUTORS.txt Support chords with CELERY_TASK_ALWAYS_EAGER (fix #4873) (#4979) Aug 15, 2018
Changelog Updated the changelog. Jul 18, 2018
LICENSE Prefer https over http when available (#3966) Apr 15, 2017
MANIFEST.in WIP: Sphinx autodoc picks up tasks automatically only if `undoc-membe… Mar 10, 2018
Makefile Fix a couple typos (#4156) Jul 26, 2017
README.rst update celery version on readme Aug 13, 2018
TODO Use https for github and wikipedia links Mar 20, 2016
appveyor.yml enable pip cache in appveyor build (#4546) Feb 20, 2018
bandit.json Add bandit baseline file with contents this time Dec 12, 2017
setup.cfg Include license file in the generated wheel package (#4404) Nov 27, 2017
setup.py added python 3.7 to classifier Jun 28, 2018
tox.ini Bump linters to Python 3.6 (#4723) May 9, 2018

README.rst

http://docs.celeryproject.org/en/latest/_images/celery-banner-small.png

Build status coverage BSD License Celery can be installed via wheel Supported Python versions. Support Python implementations. Backers on Open Collective Sponsors on Open Collective

Version:4.2.1 (latentcall)
Web:http://celeryproject.org/
Download:https://pypi.org/project/celery/
Source:https://github.com/celery/celery/
Keywords:task, queue, job, async, rabbitmq, amqp, redis, python, distributed, actors

Sponsors

ImageLink

What's a Task Queue?

Task queues are used as a mechanism to distribute work across threads or machines.

A task queue's input is a unit of work, called a task, dedicated worker processes then constantly monitor the queue for new work to perform.

Celery communicates via messages, usually using a broker to mediate between clients and workers. To initiate a task a client puts a message on the queue, the broker then delivers the message to a worker.

A Celery system can consist of multiple workers and brokers, giving way to high availability and horizontal scaling.

Celery is written in Python, but the protocol can be implemented in any language. In addition to Python there's node-celery for Node.js, and a PHP client.

Language interoperability can also be achieved by using webhooks in such a way that the client enqueues an URL to be requested by a worker.

What do I need?

Celery version 4.2 runs on,

  • Python (2.7, 3.4, 3.5, 3.6)
  • PyPy (5.8)

This is the last version to support Python 2.7, and from the next version (Celery 5.x) Python 3.5 or newer is required.

If you're running an older version of Python, you need to be running an older version of Celery:

  • Python 2.6: Celery series 3.1 or earlier.
  • Python 2.5: Celery series 3.0 or earlier.
  • Python 2.4 was Celery series 2.2 or earlier.

Celery is a project with minimal funding, so we don't support Microsoft Windows. Please don't open any issues related to that platform.

Celery is usually used with a message broker to send and receive messages. The RabbitMQ, Redis transports are feature complete, but there's also experimental support for a myriad of other solutions, including using SQLite for local development.

Celery can run on a single machine, on multiple machines, or even across datacenters.

Get Started

If this is the first time you're trying to use Celery, or you're new to Celery 4.2 coming from previous versions then you should read our getting started tutorials:

Celery is...

  • Simple

    Celery is easy to use and maintain, and does not need configuration files.

    It has an active, friendly community you can talk to for support, like at our mailing-list, or the IRC channel.

    Here's one of the simplest applications you can make:

    from celery import Celery
    
    app = Celery('hello', broker='amqp://guest@localhost//')
    
    @app.task
    def hello():
        return 'hello world'
    
  • Highly Available

    Workers and clients will automatically retry in the event of connection loss or failure, and some brokers support HA in way of Primary/Primary or Primary/Replica replication.

  • Fast

    A single Celery process can process millions of tasks a minute, with sub-millisecond round-trip latency (using RabbitMQ, py-librabbitmq, and optimized settings).

  • Flexible

    Almost every part of Celery can be extended or used on its own, Custom pool implementations, serializers, compression schemes, logging, schedulers, consumers, producers, broker transports, and much more.

It supports...

  • Message Transports

  • Concurrency

  • Result Stores

    • AMQP, Redis
    • memcached
    • SQLAlchemy, Django ORM
    • Apache Cassandra, IronCache, Elasticsearch
  • Serialization

    • pickle, json, yaml, msgpack.
    • zlib, bzip2 compression.
    • Cryptographic message signing.

Framework Integration

Celery is easy to integrate with web frameworks, some of which even have integration packages:

Django not needed
Pyramid pyramid_celery
Pylons celery-pylons
Flask not needed
web2py web2py-celery
Tornado tornado-celery

The integration packages aren't strictly necessary, but they can make development easier, and sometimes they add important hooks like closing database connections at fork.

Documentation

The latest documentation is hosted at Read The Docs, containing user guides, tutorials, and an API reference.

Installation

You can install Celery either via the Python Package Index (PyPI) or from source.

To install using pip:

$ pip install -U Celery

Bundles

Celery also defines a group of bundles that can be used to install Celery and the dependencies for a given feature.

You can specify these in your requirements or on the pip command-line by using brackets. Multiple bundles can be specified by separating them by commas.

$ pip install "celery[librabbitmq]"

$ pip install "celery[librabbitmq,redis,auth,msgpack]"

The following bundles are available:

Serializers

celery[auth]:for using the auth security serializer.
celery[msgpack]:for using the msgpack serializer.
celery[yaml]:for using the yaml serializer.

Concurrency

celery[eventlet]:for using the eventlet pool.
celery[gevent]:for using the gevent pool.

Transports and Backends

celery[librabbitmq]:

for using the librabbitmq C library.

celery[redis]:

for using Redis as a message transport or as a result backend.

celery[sqs]:

for using Amazon SQS as a message transport.

celery[tblib]:

for using the task_remote_tracebacks feature.

celery[memcache]:

for using Memcached as a result backend (using pylibmc)

celery[pymemcache]:

for using Memcached as a result backend (pure-Python implementation).

celery[cassandra]:

for using Apache Cassandra as a result backend with DataStax driver.

celery[couchbase]:

for using Couchbase as a result backend.

celery[elasticsearch]:

for using Elasticsearch as a result backend.

celery[riak]:

for using Riak as a result backend.

celery[zookeeper]:

for using Zookeeper as a message transport.

celery[sqlalchemy]:

for using SQLAlchemy as a result backend (supported).

celery[pyro]:

for using the Pyro4 message transport (experimental).

celery[slmq]:

for using the SoftLayer Message Queue transport (experimental).

celery[consul]:

for using the Consul.io Key/Value store as a message transport or result backend (experimental).

celery[django]:

specifies the lowest version possible for Django support.

You should probably not use this in your requirements, it's here for informational purposes only.

Downloading and installing from source

Download the latest version of Celery from PyPI:

https://pypi.org/project/celery/

You can install it by doing the following,:

$ tar xvfz celery-0.0.0.tar.gz
$ cd celery-0.0.0
$ python setup.py build
# python setup.py install

The last command must be executed as a privileged user if you aren't currently using a virtualenv.

Using the development version

With pip

The Celery development version also requires the development versions of kombu, amqp, billiard, and vine.

You can install the latest snapshot of these using the following pip commands:

$ pip install https://github.com/celery/celery/zipball/master#egg=celery
$ pip install https://github.com/celery/billiard/zipball/master#egg=billiard
$ pip install https://github.com/celery/py-amqp/zipball/master#egg=amqp
$ pip install https://github.com/celery/kombu/zipball/master#egg=kombu
$ pip install https://github.com/celery/vine/zipball/master#egg=vine

With git

Please see the Contributing section.

Getting Help

Mailing list

For discussions about the usage, development, and future of Celery, please join the celery-users mailing list.

IRC

Come chat with us on IRC. The #celery channel is located at the Freenode network.

Bug tracker

If you have any suggestions, bug reports, or annoyances please report them to our issue tracker at https://github.com/celery/celery/issues/

Wiki

https://wiki.github.com/celery/celery/

Credits

Contributors

This project exists thanks to all the people who contribute. Development of celery happens at GitHub: https://github.com/celery/celery

You're highly encouraged to participate in the development of celery. If you don't like GitHub (for some reason) you're welcome to send regular patches.

Be sure to also read the Contributing to Celery section in the documentation.

oc-contributors

Backers

Thank you to all our backers! 🙏 [Become a backer]

oc-backers

Sponsors

Support this project by becoming a sponsor. Your logo will show up here with a link to your website. [Become a sponsor]

oc-sponsors

License

This software is licensed under the New BSD License. See the LICENSE file in the top distribution directory for the full license text.