debian-celery/celery/app/__init__.py

151 lines
4.3 KiB
Python

# -*- coding: utf-8 -*-
"""
celery.app
~~~~~~~~~~
Celery Application.
"""
from __future__ import absolute_import
import os
from celery.local import Proxy
from celery import _state
from celery._state import (
get_current_app as current_app,
get_current_task as current_task,
connect_on_app_finalize, set_default_app, _get_active_apps, _task_stack,
)
from celery.utils import gen_task_name
from .base import Celery, AppPickler
__all__ = ['Celery', 'AppPickler', 'default_app', 'app_or_default',
'bugreport', 'enable_trace', 'disable_trace', 'shared_task',
'set_default_app', 'current_app', 'current_task',
'push_current_task', 'pop_current_task']
#: Proxy always returning the app set as default.
default_app = Proxy(lambda: _state.default_app)
#: Function returning the app provided or the default app if none.
#:
#: The environment variable :envvar:`CELERY_TRACE_APP` is used to
#: trace app leaks. When enabled an exception is raised if there
#: is no active app.
app_or_default = None
#: The 'default' loader is the default loader used by old applications.
#: This is deprecated and should no longer be used as it's set too early
#: to be affected by --loader argument.
default_loader = os.environ.get('CELERY_LOADER') or 'default' # XXX
#: Function used to push a task to the thread local stack
#: keeping track of the currently executing task.
#: You must remember to pop the task after.
push_current_task = _task_stack.push
#: Function used to pop a task from the thread local stack
#: keeping track of the currently executing task.
pop_current_task = _task_stack.pop
def bugreport(app=None):
return (app or current_app()).bugreport()
def _app_or_default(app=None):
if app is None:
return _state.get_current_app()
return app
def _app_or_default_trace(app=None): # pragma: no cover
from traceback import print_stack
from billiard import current_process
if app is None:
if getattr(_state._tls, 'current_app', None):
print('-- RETURNING TO CURRENT APP --') # noqa+
print_stack()
return _state._tls.current_app
if current_process()._name == 'MainProcess':
raise Exception('DEFAULT APP')
print('-- RETURNING TO DEFAULT APP --') # noqa+
print_stack()
return _state.default_app
return app
def enable_trace():
global app_or_default
app_or_default = _app_or_default_trace
def disable_trace():
global app_or_default
app_or_default = _app_or_default
if os.environ.get('CELERY_TRACE_APP'): # pragma: no cover
enable_trace()
else:
disable_trace()
App = Celery # XXX Compat
def shared_task(*args, **kwargs):
"""Create shared tasks (decorator).
Will return a proxy that always takes the task from the current apps
task registry.
This can be used by library authors to create tasks that will work
for any app environment.
Example:
>>> from celery import Celery, shared_task
>>> @shared_task
... def add(x, y):
... return x + y
>>> app1 = Celery(broker='amqp://')
>>> add.app is app1
True
>>> app2 = Celery(broker='redis://')
>>> add.app is app2
"""
def create_shared_task(**options):
def __inner(fun):
name = options.get('name')
# Set as shared task so that unfinalized apps,
# and future apps will load the task.
connect_on_app_finalize(
lambda app: app._task_from_fun(fun, **options)
)
# Force all finalized apps to take this task as well.
for app in _get_active_apps():
if app.finalized:
with app._finalize_mutex:
app._task_from_fun(fun, **options)
# Return a proxy that always gets the task from the current
# apps task registry.
def task_by_cons():
app = current_app()
return app.tasks[
name or gen_task_name(app, fun.__name__, fun.__module__)
]
return Proxy(task_by_cons)
return __inner
if len(args) == 1 and callable(args[0]):
return create_shared_task(**kwargs)(args[0])
return create_shared_task(*args, **kwargs)