forked from s434596/CatOrNot
113 lines
3.4 KiB
Python
113 lines
3.4 KiB
Python
|
"""Extensible memoizing collections and decorators."""
|
||
|
|
|
||
|
|
from __future__ import absolute_import
|
||
|
|
|
||
|
|
import functools
|
||
|
|
|
||
|
|
from . import keys
|
||
|
|
from .cache import Cache
|
||
|
|
from .lfu import LFUCache
|
||
|
|
from .lru import LRUCache
|
||
|
|
from .rr import RRCache
|
||
|
|
from .ttl import TTLCache
|
||
|
|
|
||
|
|
__all__ = (
|
||
|
|
'Cache', 'LFUCache', 'LRUCache', 'RRCache', 'TTLCache',
|
||
|
|
'cached', 'cachedmethod'
|
||
|
|
)
|
||
|
|
|
||
|
|
__version__ = '3.0.0'
|
||
|
|
|
||
|
|
if hasattr(functools.update_wrapper(lambda f: f(), lambda: 42), '__wrapped__'):
|
||
|
|
_update_wrapper = functools.update_wrapper
|
||
|
|
else:
|
||
|
|
def _update_wrapper(wrapper, wrapped):
|
||
|
|
functools.update_wrapper(wrapper, wrapped)
|
||
|
|
wrapper.__wrapped__ = wrapped
|
||
|
|
return wrapper
|
||
|
|
|
||
|
|
|
||
|
|
def cached(cache, key=keys.hashkey, lock=None):
|
||
|
|
"""Decorator to wrap a function with a memoizing callable that saves
|
||
|
|
results in a cache.
|
||
|
|
|
||
|
|
"""
|
||
|
|
def decorator(func):
|
||
|
|
if cache is None:
|
||
|
|
def wrapper(*args, **kwargs):
|
||
|
|
return func(*args, **kwargs)
|
||
|
|
elif lock is None:
|
||
|
|
def wrapper(*args, **kwargs):
|
||
|
|
k = key(*args, **kwargs)
|
||
|
|
try:
|
||
|
|
return cache[k]
|
||
|
|
except KeyError:
|
||
|
|
pass # key not found
|
||
|
|
v = func(*args, **kwargs)
|
||
|
|
try:
|
||
|
|
cache[k] = v
|
||
|
|
except ValueError:
|
||
|
|
pass # value too large
|
||
|
|
return v
|
||
|
|
else:
|
||
|
|
def wrapper(*args, **kwargs):
|
||
|
|
k = key(*args, **kwargs)
|
||
|
|
try:
|
||
|
|
with lock:
|
||
|
|
return cache[k]
|
||
|
|
except KeyError:
|
||
|
|
pass # key not found
|
||
|
|
v = func(*args, **kwargs)
|
||
|
|
try:
|
||
|
|
with lock:
|
||
|
|
cache[k] = v
|
||
|
|
except ValueError:
|
||
|
|
pass # value too large
|
||
|
|
return v
|
||
|
|
return _update_wrapper(wrapper, func)
|
||
|
|
return decorator
|
||
|
|
|
||
|
|
|
||
|
|
def cachedmethod(cache, key=keys.hashkey, lock=None):
|
||
|
|
"""Decorator to wrap a class or instance method with a memoizing
|
||
|
|
callable that saves results in a cache.
|
||
|
|
|
||
|
|
"""
|
||
|
|
def decorator(method):
|
||
|
|
if lock is None:
|
||
|
|
def wrapper(self, *args, **kwargs):
|
||
|
|
c = cache(self)
|
||
|
|
if c is None:
|
||
|
|
return method(self, *args, **kwargs)
|
||
|
|
k = key(*args, **kwargs)
|
||
|
|
try:
|
||
|
|
return c[k]
|
||
|
|
except KeyError:
|
||
|
|
pass # key not found
|
||
|
|
v = method(self, *args, **kwargs)
|
||
|
|
try:
|
||
|
|
c[k] = v
|
||
|
|
except ValueError:
|
||
|
|
pass # value too large
|
||
|
|
return v
|
||
|
|
else:
|
||
|
|
def wrapper(self, *args, **kwargs):
|
||
|
|
c = cache(self)
|
||
|
|
if c is None:
|
||
|
|
return method(self, *args, **kwargs)
|
||
|
|
k = key(*args, **kwargs)
|
||
|
|
try:
|
||
|
|
with lock(self):
|
||
|
|
return c[k]
|
||
|
|
except KeyError:
|
||
|
|
pass # key not found
|
||
|
|
v = method(self, *args, **kwargs)
|
||
|
|
try:
|
||
|
|
with lock(self):
|
||
|
|
c[k] = v
|
||
|
|
except ValueError:
|
||
|
|
pass # value too large
|
||
|
|
return v
|
||
|
|
return _update_wrapper(wrapper, method)
|
||
|
|
return decorator
|