# -*- coding: utf-8 -*-
import collections
import six
from functools import update_wrapper
from easy_cache.core import Cached, TaggedCached, DEFAULT_TIMEOUT, META_ACCEPTED_ATTR
# noinspection PyPep8Naming
class ecached(object):
""" Caches result of decorated callable.
Possible use-cases are:
@cached()
def func(...):
@cached('cache_key') # cache key only
def func(...):
@cached('cache_key', 300) # cache key and timeout in seconds
def func(...):
@cached('cache_key', 300, ('user', 'books')) # + tags
def func(...):
@cached('{a}:{b}')
def func(a, b): # cache keys based on method parameters
@cached(['a', 'b'])
def func(a, b): # cache keys based on method parameters
@cached(callable_with_parameters)
def func(a, b): # cache_key = callable_with_parameters(a, b)
"""
def __init__(self, cache_key=None, timeout=DEFAULT_TIMEOUT, tags=(), prefix=None,
cache_instance=None, cache_alias=None):
if tags or prefix:
self.cache = TaggedCached(
function=None,
cache_key=cache_key,
tags=tags,
timeout=timeout,
prefix=prefix,
cache_instance=cache_instance,
cache_alias=cache_alias,
)
else:
self.cache = Cached(
function=None,
cache_key=cache_key,
timeout=timeout,
cache_instance=cache_instance,
cache_alias=cache_alias,
)
self._instance = None
self._class = None
self._func = None
self._wrapped = False
def __get__(self, instance, owner):
self._instance = instance
self._class = owner
return self.wrapper()
def wrapper(self):
if not self._wrapped:
if self._instance or self._class:
wrapped = self._func.__get__(self._instance, self._class)
if isinstance(self._func, staticmethod):
# we don't need instance or class, however we need scope
self.cache.scope = self._instance or self._class
self._instance = None
self._class = None
else:
wrapped = six.get_method_function(wrapped)
else:
wrapped = self._func
update_wrapper(self.cache, wrapped)
self.cache.function = wrapped
self.cache.instance = self._instance
self.cache.klass = self._class
self._wrapped = True
return self.cache
def __call__(self, func):
self._func = func
if isinstance(func, collections.Callable):
return self.wrapper()
return self
def __repr__(self):
return repr(self.cache)
def ecached_property(cache_key=None, timeout=DEFAULT_TIMEOUT, tags=(), prefix=None,
cache_instance=None, cache_alias=None):
""" Works the same as `cached` decorator, but intended to use
for properties, e.g.:
class User(object):
@cached_property('{self.id}:friends_count', 120)
def friends_count(self):
return <calculated friends count>
"""
def wrapper(func):
if tags or prefix:
cache = TaggedCached(
function=func,
cache_key=cache_key,
tags=tags,
timeout=timeout,
prefix=prefix,
cache_instance=cache_instance,
cache_alias=cache_alias,
as_property=True,
)
else:
cache = Cached(
function=func,
cache_key=cache_key,
timeout=timeout,
cache_instance=cache_instance,
cache_alias=cache_alias,
as_property=True,
)
return cache
return wrapper
def meta_accepted(func):
if isinstance(func, (staticmethod, classmethod)):
_func = func.__func__
else:
_func = func
setattr(_func, META_ACCEPTED_ATTR, True)
return func
