redis-cached 0.3.0

Python cache decorator and other itils with support for Redis or KeyDB

redis-cached

Python cache decorator that uses Redis or KeyDB as storage. This is very handy for replicated apps (e.g. Kubernetes), AWS Lambda functions, and other stateless apps.

Features:

• Function result and kwarg values are pickled, so you can work with complex structures like pydantic's BaseModel
• Prevents multiple simultaneous cache updates when a function is called concurrently and there is no cached value.
• Cache invalidation is available

Limitations:

• Only async functions are supported.
• Only keyword arguments are supported. It will raise an error if you pass non-kwargs while calling your function.

Installation

pip install redis_cached

Usage

Basic usage:

import asyncio
from redis_cached import cached, invalidate_cache

@cached(5)
async def add_one(x):
    return x + 1

async def main():
    result = await add_one(x=2)  # result is cached for 5 seconds
    
    # Pass the same kwargs to this func to invalidate the cache
    await invalidate_cache('add_one', x=2)

asyncio.run(main())

Optionally, add salt to the decorator to avoid clashing with the same-named functions in other modules or other apps that use the same Redis or KeyDB database:

import asyncio
from redis_cached import cached, invalidate_cache

CACHE_SALT = 'XnsJ-7C9PIU0qhDwh9YhJQ'

@cached(5, cache_key_salt=CACHE_SALT)
async def add_one(x):
    return x + 1

async def invalidate_add_one(**kwargs):
    await invalidate_cache('add_one', cache_key_salt=CACHE_SALT, **kwargs)

async def main():
    result = await add_one(x=2)  # cached
    await invalidate_add_one(x=2)  # invalidated

asyncio.run(main())

Contributing

Contributions are welcome. Please refer to maintenance readme for more details.