async-lru
info: | Simple lru cache for asyncio |
---|
Installation
pip install async-lru
Usage
This package is a port of Python's built-in functools.lru_cache function for asyncio. To better handle async behaviour, it also ensures multiple concurrent calls will only result in 1 call to the wrapped function, with all await
s receiving the result of that call when it completes.
import asyncio
import aiohttp
from async_lru import alru_cache
@alru_cache(maxsize=32)
async def get_pep(num):
resource = 'http://www.python.org/dev/peps/pep-%04d/' % num
async with aiohttp.ClientSession() as session:
try:
async with session.get(resource) as s:
return await s.read()
except aiohttp.ClientError:
return 'Not Found'
async def main():
for n in 8, 290, 308, 320, 8, 218, 320, 279, 289, 320, 9991:
pep = await get_pep(n)
print(n, len(pep))
print(get_pep.cache_info())
# CacheInfo(hits=3, misses=8, maxsize=32, currsize=8)
# closing is optional, but highly recommended
await get_pep.cache_close()
asyncio.run(main())
TTL (time-to-live, expiration on timeout) is supported by accepting ttl configuration parameter (off by default):
@alru_cache(ttl=5)
async def func(arg):
return arg * 2
The library supports explicit invalidation for specific function call by cache_invalidate():
@alru_cache(ttl=5)
async def func(arg1, arg2):
return arg1 + arg2
func.cache_invalidate(1, arg2=2)
The method returns True if corresponding arguments set was cached already, False otherwise.
Python 3.8+ is required
Thanks
The library was donated by Ocean S.A.
Thanks to the company for contribution.