34 lines
809 B
Python
34 lines
809 B
Python
"""
|
|
Async utils no one seems to have built into a core lib (yet).
|
|
"""
|
|
from collections import OrderedDict
|
|
|
|
|
|
def async_lifo_cache(maxsize=128):
|
|
"""Async ``cache`` with a LIFO policy.
|
|
|
|
Implemented my own since no one else seems to have
|
|
a standard. I'll wait for the smarter people to come
|
|
up with one, but until then...
|
|
"""
|
|
cache = OrderedDict()
|
|
|
|
def decorator(fn):
|
|
|
|
async def wrapper(*args):
|
|
key = args
|
|
try:
|
|
return cache[key]
|
|
except KeyError:
|
|
if len(cache) >= maxsize:
|
|
# discard last added new entry
|
|
cache.popitem()
|
|
|
|
# do it
|
|
cache[key] = await fn(*args)
|
|
return cache[key]
|
|
|
|
return wrapper
|
|
|
|
return decorator
|