cache-sync 0.4.0

Async hybrid Python cache with in-memory L1, distributed L2 providers, pluggable invalidation, stampede protection, and typed decorators.

cache-sync

Async hybrid Python cache with in-memory L1 caching, optional Redis L2 caching, pluggable invalidation, stampede protection, fail-safe stale values, and typed decorators.

Features

• Async-first API for Python 3.12 and newer.
• Fast in-process L1 cache with optional Redis-backed L2 storage.
• Pluggable invalidation buses for Redis Streams, RabbitMQ, Kafka, and PostgreSQL.
• Request stampede protection with per-key refresh coordination.
• Fail-safe stale reads for short backend outages.
• Typed decorators that preserve the wrapped function signature.
• Serializer choices for JSON, pickle, and Pydantic models.

Documentation

The end-user documentation is published at https://petercinibulk.github.io/cache-sync/ and is built from docs/ with Zensical.

Install

uv add cache-sync

Install optional providers only when your application uses them:

uv add "cache-sync[redis]"
uv add "cache-sync[rabbitmq]"
uv add "cache-sync[kafka]"
uv add "cache-sync[postgres]"
uv add "cache-sync[all]"

Extra	Installs	Use when
redis	redis	You need Redis L2 storage or Redis Streams invalidation.
rabbitmq	aio-pika	You use RabbitMQ as the invalidation bus.
kafka	aiokafka	You use Kafka as the invalidation bus.
postgres	asyncpg	You use PostgreSQL LISTEN/NOTIFY for invalidation.
pydantic	pydantic	You want Pydantic model serialization helpers.
all	all provider dependencies	You want every optional provider available.

Quick Start

from cache_sync import CacheOptions, CacheSync

cache = CacheSync(
    options=CacheOptions(
        ttl_seconds=60,
        fail_safe_seconds=300,
        hard_timeout_seconds=5,
        jitter_seconds=5,
    ),
)

await cache.start()


@cache.cached(lambda user_id: f"user:{user_id}")
async def get_user(user_id: str) -> dict[str, str]:
    return {"id": user_id, "name": "Peter"}


user = await get_user("123")
await get_user.remove_cached("123")
await cache.stop()

Redis L2 Example

from redis.asyncio import Redis

from cache_sync import CacheOptions, CacheSync, RedisDistributedCache

redis = Redis.from_url("redis://localhost:6379/0")

cache = CacheSync(
    distributed_cache=RedisDistributedCache(redis),
    options=CacheOptions(ttl_seconds=60, fail_safe_seconds=300),
)

await cache.start()


@cache.cached(lambda product_id: f"product:{product_id}")
async def get_product(product_id: str) -> dict[str, str]:
    return {"id": product_id}

For a complete walkthrough with shared values and cross-instance invalidation, see the get started tutorial.

Project

• License: MIT
• Source: https://github.com/petercinibulk/cache-sync
• Issues: https://github.com/petercinibulk/cache-sync/issues