This document describes the current stable version of Celery (3.1). For development docs, go here.

Source code for celery

# -*- coding: utf-8 -*-
"""Distributed Task Queue"""
# :copyright: (c) 2009 - 2012 Ask Solem and individual contributors,
#                 All rights reserved.
# :copyright: (c) 2012-2013 GoPivotal, Inc., All rights reserved.
# :license:   BSD (3 Clause), see LICENSE for more details.

from __future__ import absolute_import

from collections import namedtuple

version_info_t = namedtuple(
    'version_info_t', ('major', 'minor', 'micro', 'releaselevel', 'serial'),
)

SERIES = 'Cipater'
VERSION = version_info_t(3, 1, 11, '', '')
__version__ = '{0.major}.{0.minor}.{0.micro}{0.releaselevel}'.format(VERSION)
__author__ = 'Ask Solem'
__contact__ = 'ask@celeryproject.org'
__homepage__ = 'http://celeryproject.org'
__docformat__ = 'restructuredtext'
__all__ = [
    'Celery', 'bugreport', 'shared_task', 'task',
    'current_app', 'current_task', 'maybe_signature',
    'chain', 'chord', 'chunks', 'group', 'signature',
    'xmap', 'xstarmap', 'uuid', 'version', '__version__',
]
VERSION_BANNER = '{0} ({1})'.format(__version__, SERIES)

# -eof meta-

import os
import sys
if os.environ.get('C_IMPDEBUG'):  # pragma: no cover
    from .five import builtins
    real_import = builtins.__import__

    def debug_import(name, locals=None, globals=None,
                     fromlist=None, level=-1):
        glob = globals or getattr(sys, 'emarfteg_'[::-1])(1).f_globals
        importer_name = glob and glob.get('__name__') or 'unknown'
        print('-- {0} imports {1}'.format(importer_name, name))
        return real_import(name, locals, globals, fromlist, level)
    builtins.__import__ = debug_import

# This is never executed, but tricks static analyzers (PyDev, PyCharm,
# pylint, etc.) into knowing the types of these symbols, and what
# they contain.
STATICA_HACK = True
globals()['kcah_acitats'[::-1].upper()] = False
if STATICA_HACK:  # pragma: no cover
    from celery.app import shared_task                   # noqa
    from celery.app.base import Celery                   # noqa
    from celery.app.utils import bugreport               # noqa
    from celery.app.task import Task                     # noqa
    from celery._state import current_app, current_task  # noqa
    from celery.canvas import (                          # noqa
        chain, chord, chunks, group,
        signature, maybe_signature, xmap, xstarmap, subtask,
    )
    from celery.utils import uuid                        # noqa

# Eventlet/gevent patching must happen before importing
# anything else, so these tools must be at top-level.


def _find_option_with_arg(argv, short_opts=None, long_opts=None):
    """Search argv for option specifying its short and longopt
    alternatives.

    Return the value of the option if found.

    """
    for i, arg in enumerate(argv):
        if arg.startswith('-'):
            if long_opts and arg.startswith('--'):
                name, _, val = arg.partition('=')
                if name in long_opts:
                    return val
            if short_opts and arg in short_opts:
                return argv[i + 1]
    raise KeyError('|'.join(short_opts or [] + long_opts or []))


def _patch_eventlet():
    import eventlet
    import eventlet.debug
    eventlet.monkey_patch()
    EVENTLET_DBLOCK = int(os.environ.get('EVENTLET_NOBLOCK', 0))
    if EVENTLET_DBLOCK:
        eventlet.debug.hub_blocking_detection(EVENTLET_DBLOCK)


def _patch_gevent():
    from gevent import monkey, version_info
    monkey.patch_all()
    if version_info[0] == 0:  # pragma: no cover
        # Signals aren't working in gevent versions <1.0,
        # and are not monkey patched by patch_all()
        from gevent import signal as _gevent_signal
        _signal = __import__('signal')
        _signal.signal = _gevent_signal


def maybe_patch_concurrency(argv=sys.argv,
                            short_opts=['-P'], long_opts=['--pool'],
                            patches={'eventlet': _patch_eventlet,
                                     'gevent': _patch_gevent}):
    """With short and long opt alternatives that specify the command line
    option to set the pool, this makes sure that anything that needs
    to be patched is completed as early as possible.
    (e.g. eventlet/gevent monkey patches)."""
    try:
        pool = _find_option_with_arg(argv, short_opts, long_opts)
    except KeyError:
        pass
    else:
        try:
            patcher = patches[pool]
        except KeyError:
            pass
        else:
            patcher()
        # set up eventlet/gevent environments ASAP.
        from celery import concurrency
        concurrency.get_implementation(pool)

# Lazy loading
from celery import five

old_module, new_module = five.recreate_module(  # pragma: no cover
    __name__,
    by_module={
        'celery.app': ['Celery', 'bugreport', 'shared_task'],
        'celery.app.task': ['Task'],
        'celery._state': ['current_app', 'current_task'],
        'celery.canvas': ['chain', 'chord', 'chunks', 'group',
                          'signature', 'maybe_signature', 'subtask',
                          'xmap', 'xstarmap'],
        'celery.utils': ['uuid'],
    },
    direct={'task': 'celery.task'},
    __package__='celery', __file__=__file__,
    __path__=__path__, __doc__=__doc__, __version__=__version__,
    __author__=__author__, __contact__=__contact__,
    __homepage__=__homepage__, __docformat__=__docformat__, five=five,
    VERSION=VERSION, SERIES=SERIES, VERSION_BANNER=VERSION_BANNER,
    version_info_t=version_info_t,
    maybe_patch_concurrency=maybe_patch_concurrency,
    _find_option_with_arg=_find_option_with_arg,
)