This document describes the current stable version of Celery (4.4). For development docs, go here.

Source code for kombu.utils.objects

"""Object Utilities."""
from __future__ import absolute_import, unicode_literals

[docs]class cached_property(object): """Cached property descriptor. Caches the return value of the get method on first call. Examples: .. code-block:: python @cached_property def connection(self): return Connection() @connection.setter # Prepares stored value def connection(self, value): if value is None: raise TypeError('Connection must be a connection') return value @connection.deleter def connection(self, value): # Additional action to do at del(self.attr) if value is not None: print('Connection {0!r} deleted'.format(value) """ def __init__(self, fget=None, fset=None, fdel=None, doc=None): self.__get = fget self.__set = fset self.__del = fdel self.__doc__ = doc or fget.__doc__ self.__name__ = fget.__name__ self.__module__ = fget.__module__ def __get__(self, obj, type=None): if obj is None: return self try: return obj.__dict__[self.__name__] except KeyError: value = obj.__dict__[self.__name__] = self.__get(obj) return value def __set__(self, obj, value): if obj is None: return self if self.__set is not None: value = self.__set(obj, value) obj.__dict__[self.__name__] = value def __delete__(self, obj, _sentinel=object()): if obj is None: return self value = obj.__dict__.pop(self.__name__, _sentinel) if self.__del is not None and value is not _sentinel: self.__del(obj, value)
[docs] def setter(self, fset): return self.__class__(self.__get, fset, self.__del)
[docs] def deleter(self, fdel): return self.__class__(self.__get, self.__set, fdel)