debian-celery/celery/app/annotations.py

59 lines
1.5 KiB
Python

# -*- coding: utf-8 -*-
"""
celery.app.annotations
~~~~~~~~~~~~~~~~~~~~~~
Annotations is a nice term for moneky patching
task classes in the configuration.
This prepares and performs the annotations in the
:setting:`CELERY_ANNOTATIONS` setting.
"""
from __future__ import absolute_import
from celery.five import string_t
from celery.utils.functional import firstmethod, mlazy
from celery.utils.imports import instantiate
_first_match = firstmethod('annotate')
_first_match_any = firstmethod('annotate_any')
__all__ = ['MapAnnotation', 'prepare', 'resolve_all']
class MapAnnotation(dict):
def annotate_any(self):
try:
return dict(self['*'])
except KeyError:
pass
def annotate(self, task):
try:
return dict(self[task.name])
except KeyError:
pass
def prepare(annotations):
"""Expands the :setting:`CELERY_ANNOTATIONS` setting."""
def expand_annotation(annotation):
if isinstance(annotation, dict):
return MapAnnotation(annotation)
elif isinstance(annotation, string_t):
return mlazy(instantiate, annotation)
return annotation
if annotations is None:
return ()
elif not isinstance(annotations, (list, tuple)):
annotations = (annotations, )
return [expand_annotation(anno) for anno in annotations]
def resolve_all(anno, task):
return (x for x in (_first_match(anno, task), _first_match_any(anno)) if x)