This document describes an older version of Celery (2.5). For the latest stable version please go here.

celery.utils

celery.utils

Utility functions.

copyright:

3. 2009 - 2012 by Ask Solem.

license:

BSD, see LICENSE for more details.

exception celery.utils.NotAPackage

celery.utils.abbr(S, max, ellipsis='...')

celery.utils.abbrtask(S, max)

celery.utils.chunks(it, n)

Split an iterator into chunks with n elements each.

Examples

# n == 2 >>> x = chunks(iter([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]), 2) >>> list(x) [[0, 1], [2, 3], [4, 5], [6, 7], [8, 9], [10]]

# n == 3 >>> x = chunks(iter([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]), 3) >>> list(x) [[0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10]]

celery.utils.cry()

Return stacktrace of all active threads.

From https://gist.github.com/737056

celery.utils.cwd_in_path(*args, **kwds)

celery.utils.deprecated(description=None, deprecation=None, removal=None, alternative=None)

celery.utils.find_module(module, path=None, imp=None)

Version of imp.find_module() supporting dots.

celery.utils.first(predicate, iterable)

Returns the first element in iterable that predicate returns a True value for.

celery.utils.firstmethod(method)

Returns a functions that with a list of instances, finds the first instance that returns a value for the given method.

The list can also contain promises (promise.)

celery.utils.fun_takes_kwargs(fun, kwlist=[])

With a function, and a list of keyword arguments, returns arguments in the list which the function takes.

If the object has an argspec attribute that is used instead of using the inspect.getargspec() introspection.

Parameters:

• fun – The function to inspect arguments of.
• kwlist – The list of keyword arguments.

Examples

>>> def foo(self, x, y, logfile=None, loglevel=None):
...     return x * y
>>> fun_takes_kwargs(foo, ["logfile", "loglevel", "task_id"])
["logfile", "loglevel"]

>>> def foo(self, x, y, **kwargs):
>>> fun_takes_kwargs(foo, ["logfile", "loglevel", "task_id"])
["logfile", "loglevel", "task_id"]

celery.utils.get_cls_by_name(name, aliases={}, imp=None, package=None, sep='.', **kwargs)

Get class by name.

The name should be the full dot-separated path to the class:

modulename.ClassName

Example:

celery.concurrency.processes.TaskPool
                            ^- class name

or using ‘:’ to separate module and symbol:

celery.concurrency.processes:TaskPool

If aliases is provided, a dict containing short name/long name mappings, the name is looked up in the aliases first.

Examples:

>>> get_cls_by_name("celery.concurrency.processes.TaskPool")
<class 'celery.concurrency.processes.TaskPool'>

>>> get_cls_by_name("default", {
...     "default": "celery.concurrency.processes.TaskPool"})
<class 'celery.concurrency.processes.TaskPool'>

# Does not try to look up non-string names. >>> from celery.concurrency.processes import TaskPool >>> get_cls_by_name(TaskPool) is TaskPool True

celery.utils.get_full_cls_name(obj)

celery.utils.get_symbol_by_name(name, aliases={}, imp=None, package=None, sep='.', **kwargs)

Get class by name.

The name should be the full dot-separated path to the class:

modulename.ClassName

Example:

celery.concurrency.processes.TaskPool
                            ^- class name

or using ‘:’ to separate module and symbol:

celery.concurrency.processes:TaskPool

If aliases is provided, a dict containing short name/long name mappings, the name is looked up in the aliases first.

Examples:

>>> get_cls_by_name("celery.concurrency.processes.TaskPool")
<class 'celery.concurrency.processes.TaskPool'>

>>> get_cls_by_name("default", {
...     "default": "celery.concurrency.processes.TaskPool"})
<class 'celery.concurrency.processes.TaskPool'>

# Does not try to look up non-string names. >>> from celery.concurrency.processes import TaskPool >>> get_cls_by_name(TaskPool) is TaskPool True

celery.utils.import_from_cwd(module, imp=None, package=None)

Import module, but make sure it finds modules located in the current directory.

Modules located in the current directory has precedence over modules located in sys.path.

celery.utils.instantiate(name, *args, **kwargs)

Instantiate class by name.

See get_cls_by_name().

celery.utils.is_iterable(obj)

celery.utils.isatty(fh)

celery.utils.lpmerge(L, R)

Left precedent dictionary merge. Keeps values from l, if the value in r is None.

celery.utils.mattrgetter(*attrs)

Like operator.itemgetter() but returns None on missing attributes instead of raising AttributeError.

celery.utils.maybe_reraise()

Reraise if an exception is currently being handled, or return otherwise.

celery.utils.module_file(module)

class celery.utils.mpromise(fun, *args, **kwargs)

Memoized promise.

The function is only evaluated once, every subsequent access will return the same value.

evaluated

Set to to True after the promise has been evaluated.

evaluate()

evaluated = False

celery.utils.noop(*args, **kwargs)

No operation.

Takes any arguments/keyword arguments and does nothing.

celery.utils.padlist(container, size, default=None)

Pad list with default elements.

Examples:

>>> first, last, city = padlist(["George", "Costanza", "NYC"], 3)
("George", "Costanza", "NYC")
>>> first, last, city = padlist(["George", "Costanza"], 3)
("George", "Costanza", None)
>>> first, last, city, planet = padlist(["George", "Costanza",
                                         "NYC"], 4, default="Earth")
("George", "Costanza", "NYC", "Earth")

celery.utils.pluralize(n, text, suffix='s')

celery.utils.qualname(obj)

celery.utils.reload_from_cwd(module, reloader=None)

celery.utils.textindent(t, indent=0)

Indent text.

celery.utils.truncate_text(text, maxlen=128, suffix='...')

Truncates text to a maximum number of characters.

celery.utils.uniq(it)

celery.utils.warn_deprecated(description=None, deprecation=None, removal=None, alternative=None)