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Cache Backends API

Backend implementations for in-memory, Redis, and file-system storage.

Backend Base and Factory

BaseBackend

BaseBackend

Bases: CacheInterface, AsyncCacheInterface

Common backend base with serialization support.

Source code in src/jinpy_utils/cache/backends.py 
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class BaseBackend(CacheInterface, AsyncCacheInterface):
    """Common backend base with serialization support."""

    _async_capable: ClassVar[bool] = True

    def __init__(
        self,
        name: str,
        serializer: tuple[Callable[[Any], bytes], Callable[[bytes], Any]],
        default_ttl: float | None,
    ) -> None:
        self.name = name
        self._ser, self._de = serializer
        self._default_ttl = default_ttl

    # Sync API default: delegate to async if not overridden
    def get(self, key: str) -> Any | None:
        return asyncio.run(self.aget(key))

    def set(self, key: str, value: Any, ttl: float | None = None) -> None:
        asyncio.run(self.aset(key, value, ttl))

    def delete(self, key: str) -> None:
        asyncio.run(self.adelete(key))

    def exists(self, key: str) -> bool:
        return asyncio.run(self.aexists(key))

    def clear(self) -> None:
        asyncio.run(self.aclear())

    def get_many(self, keys: list[str]) -> dict[str, Any | None]:
        return asyncio.run(self.aget_many(keys))

    def set_many(self, items: Mapping[str, Any], ttl: float | None = None) -> None:
        asyncio.run(self.aset_many(items, ttl))

    def delete_many(self, keys: list[str]) -> None:
        asyncio.run(self.adelete_many(keys))

    def incr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        return asyncio.run(self.aincr(key, amount, ttl))

    def decr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        return asyncio.run(self.adecr(key, amount, ttl))

    def ttl(self, key: str) -> float | None:
        return asyncio.run(self.attl(key))

    def touch(self, key: str, ttl: float) -> None:
        asyncio.run(self.atouch(key, ttl))

    def is_healthy(self) -> bool:
        return asyncio.run(self.ais_healthy())

    def close(self) -> None:
        asyncio.run(self.aclose())

Functions

get 

get(key: str) -> Any | None
Source code in src/jinpy_utils/cache/backends.py 
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def get(self, key: str) -> Any | None:
    return asyncio.run(self.aget(key))

set 

set(key: str, value: Any, ttl: float | None = None) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def set(self, key: str, value: Any, ttl: float | None = None) -> None:
    asyncio.run(self.aset(key, value, ttl))

delete 

delete(key: str) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def delete(self, key: str) -> None:
    asyncio.run(self.adelete(key))

exists 

exists(key: str) -> bool
Source code in src/jinpy_utils/cache/backends.py 
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def exists(self, key: str) -> bool:
    return asyncio.run(self.aexists(key))

clear 

clear() -> None
Source code in src/jinpy_utils/cache/backends.py 
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def clear(self) -> None:
    asyncio.run(self.aclear())

get_many 

get_many(keys: list[str]) -> dict[str, Any | None]
Source code in src/jinpy_utils/cache/backends.py 
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def get_many(self, keys: list[str]) -> dict[str, Any | None]:
    return asyncio.run(self.aget_many(keys))

set_many 

set_many(items: Mapping[str, Any], ttl: float | None = None) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def set_many(self, items: Mapping[str, Any], ttl: float | None = None) -> None:
    asyncio.run(self.aset_many(items, ttl))

delete_many 

delete_many(keys: list[str]) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def delete_many(self, keys: list[str]) -> None:
    asyncio.run(self.adelete_many(keys))

incr 

incr(key: str, amount: int = 1, ttl: float | None = None) -> int
Source code in src/jinpy_utils/cache/backends.py 
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def incr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
    return asyncio.run(self.aincr(key, amount, ttl))

decr 

decr(key: str, amount: int = 1, ttl: float | None = None) -> int
Source code in src/jinpy_utils/cache/backends.py 
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def decr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
    return asyncio.run(self.adecr(key, amount, ttl))

ttl 

ttl(key: str) -> float | None
Source code in src/jinpy_utils/cache/backends.py 
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def ttl(self, key: str) -> float | None:
    return asyncio.run(self.attl(key))

touch 

touch(key: str, ttl: float) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def touch(self, key: str, ttl: float) -> None:
    asyncio.run(self.atouch(key, ttl))

is_healthy 

is_healthy() -> bool
Source code in src/jinpy_utils/cache/backends.py 
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def is_healthy(self) -> bool:
    return asyncio.run(self.ais_healthy())

close 

close() -> None
Source code in src/jinpy_utils/cache/backends.py 
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def close(self) -> None:
    asyncio.run(self.aclose())

CacheBackendFactory

CacheBackendFactory

Factory for creating cache backend instances.

Source code in src/jinpy_utils/cache/backends.py 
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class CacheBackendFactory:
    """Factory for creating cache backend instances."""

    @staticmethod
    def create(
        config: MemoryCacheConfig | RedisCacheConfig | FileCacheConfig,
    ) -> BaseBackend:
        if isinstance(config, MemoryCacheConfig):
            return MemoryCacheBackend(config)
        if isinstance(config, RedisCacheConfig):
            return RedisCacheBackend(config)
        if isinstance(config, FileCacheConfig):
            return FileCacheBackend(config)
        raise CacheBackendError(
            message=f"Unsupported backend config: {type(config).__name__}",
            backend_name=getattr(config, "name", None),
        )

Functions

create staticmethod 

create(
    config: MemoryCacheConfig | RedisCacheConfig | FileCacheConfig,
) -> BaseBackend
Source code in src/jinpy_utils/cache/backends.py 
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@staticmethod
def create(
    config: MemoryCacheConfig | RedisCacheConfig | FileCacheConfig,
) -> BaseBackend:
    if isinstance(config, MemoryCacheConfig):
        return MemoryCacheBackend(config)
    if isinstance(config, RedisCacheConfig):
        return RedisCacheBackend(config)
    if isinstance(config, FileCacheConfig):
        return FileCacheBackend(config)
    raise CacheBackendError(
        message=f"Unsupported backend config: {type(config).__name__}",
        backend_name=getattr(config, "name", None),
    )

In-Memory Backend

MemoryCacheBackend

MemoryCacheBackend

Bases: BaseBackend

In-memory cache with optional size limit and TTL.

Source code in src/jinpy_utils/cache/backends.py 
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class MemoryCacheBackend(BaseBackend):
    """In-memory cache with optional size limit and TTL."""

    def __init__(self, config: MemoryCacheConfig) -> None:
        ser = default_serializer(config.serializer)
        super().__init__(config.name, ser, config.default_ttl)
        self._store: dict[str, tuple[bytes, float | None]] = {}
        self._lock = asyncio.Lock() if config.thread_safe else None
        self._max_entries = config.max_entries

    async def _with_lock(self, coro: Coroutine) -> Awaitable[Coroutine]:
        if self._lock is None:
            return cast("Awaitable", await coro)
        async with self._lock:
            return cast("Awaitable", await coro)

    async def aget(self, key: str) -> Any | None:
        k = normalize_key(key)

        async def _get() -> Any | None:
            entry = self._store.get(k)
            if not entry:
                return None
            data, expiry = entry
            if expiry is not None and remaining_ttl(expiry) == 0:
                self._store.pop(k, None)
                return None
            try:
                return self._de(data)
            except Exception as e:
                raise CacheSerializationError(
                    message=f"Deserialization failed: {e}",
                    cache_key=k,
                    backend_name=self.name,
                    operation=CacheOperation.GET,
                ) from e

        return await self._with_lock(_get())

    async def aset(self, key: str, value: Any, ttl: float | None = None) -> None:
        k = normalize_key(key)
        expiry = compute_expiry(ttl if ttl is not None else self._default_ttl)

        async def _set() -> None:
            try:
                data = self._ser(value)
            except Exception as e:
                raise CacheSerializationError(
                    message=f"Serialization failed: {e}",
                    cache_key=k,
                    backend_name=self.name,
                    operation=CacheOperation.SET,
                ) from e
            self._store[k] = (data, expiry)
            if self._max_entries and len(self._store) > self._max_entries:
                # Simple FIFO eviction
                first_key = next(iter(self._store.keys()))
                self._store.pop(first_key, None)

        await self._with_lock(_set())

    async def adelete(self, key: str) -> None:
        k = normalize_key(key)

        async def _del() -> None:
            self._store.pop(k, None)

        await self._with_lock(_del())

    async def aexists(self, key: str) -> bool:
        k = normalize_key(key)

        async def _exists() -> bool:
            entry = self._store.get(k)
            if not entry:
                return False
            _, expiry = entry
            if expiry is not None and remaining_ttl(expiry) == 0:
                self._store.pop(k, None)
                return False
            return True

        return cast("bool", await self._with_lock(_exists()))

    async def aclear(self) -> None:
        async def _clear() -> None:
            self._store.clear()

        await self._with_lock(_clear())

    async def aget_many(self, keys: list[str]) -> dict[str, Any | None]:
        async def _get_many() -> dict[str, Any | None]:
            result: dict[str, Any | None] = {}
            for key in keys:
                k = normalize_key(key)
                entry = self._store.get(k)
                if not entry:
                    result[key] = None
                    continue
                data, expiry = entry
                if expiry is not None and remaining_ttl(expiry) == 0:
                    self._store.pop(k, None)
                    result[key] = None
                    continue
                try:
                    result[key] = self._de(data)
                except Exception as e:
                    raise CacheSerializationError(
                        message=f"Deserialization failed: {e}",
                        cache_key=k,
                        backend_name=self.name,
                        operation=CacheOperation.GET,
                    ) from e
            return result

        return cast("dict[str, Any | None]", await self._with_lock(_get_many()))

    async def aset_many(
        self, items: Mapping[str, Any], ttl: float | None = None
    ) -> None:
        async def _set_many() -> None:
            expiry_default = compute_expiry(
                ttl if ttl is not None else self._default_ttl
            )
            for k, v in items.items():
                nk = normalize_key(k)
                # Recompute expiry per item to reflect current time consistently
                expiry = (
                    expiry_default
                    if ttl is not None or self._default_ttl is not None
                    else None
                )
                if ttl is not None and ttl <= 0:
                    expiry = compute_expiry(ttl)
                elif ttl is None and self._default_ttl is not None:
                    expiry = compute_expiry(self._default_ttl)
                try:
                    raw = self._ser(v)
                except Exception as e:
                    raise CacheSerializationError(
                        message=f"Serialization failed: {e}",
                        cache_key=k,
                        backend_name=self.name,
                        operation=CacheOperation.SET,
                    ) from e
                self._store[nk] = (raw, expiry)
                if self._max_entries and len(self._store) > self._max_entries:
                    first_key = next(iter(self._store.keys()))
                    self._store.pop(first_key, None)

        await self._with_lock(_set_many())

    async def adelete_many(self, keys: list[str]) -> None:
        async def _del_many() -> None:
            for k in keys:
                nk = normalize_key(k)
                self._store.pop(nk, None)

        await self._with_lock(_del_many())

    async def aincr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        if amount < 0:
            raise CacheKeyError(
                "Amount must be non-negative",
                cache_key=key,
                backend_name=self.name,
                operation=CacheOperation.INCR,
            )
        val = await self.aget(key)
        new_val = (int(val) if val is not None else 0) + amount
        await self.aset(key, new_val, ttl)
        return new_val

    async def adecr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        if amount < 0:
            raise CacheKeyError(
                "Amount must be non-negative",
                cache_key=key,
                backend_name=self.name,
                operation=CacheOperation.DECR,
            )
        val = await self.aget(key)
        new_val = (int(val) if val is not None else 0) - amount
        await self.aset(key, new_val, ttl)
        return new_val

    async def attl(self, key: str) -> float | None:
        k = normalize_key(key)

        async def _ttl() -> float | None:
            entry = self._store.get(k)
            if not entry:
                return None
            _, expiry = entry
            return remaining_ttl(expiry)

        return cast("float | None", await self._with_lock(_ttl()))

    async def atouch(self, key: str, ttl: float) -> None:
        k = normalize_key(key)

        async def _touch() -> None:
            entry = self._store.get(k)
            if not entry:
                return
            data, _ = entry
            self._store[k] = (data, compute_expiry(ttl))

        await self._with_lock(_touch())

    async def ais_healthy(self) -> bool:
        return True

    async def aclose(self) -> None:
        await self.aclear()

Functions

__init__ 

__init__(config: MemoryCacheConfig) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def __init__(self, config: MemoryCacheConfig) -> None:
    ser = default_serializer(config.serializer)
    super().__init__(config.name, ser, config.default_ttl)
    self._store: dict[str, tuple[bytes, float | None]] = {}
    self._lock = asyncio.Lock() if config.thread_safe else None
    self._max_entries = config.max_entries

Redis Backend

RedisCacheBackend

RedisCacheBackend

Bases: BaseBackend

Async Redis backend. Requires redis-py[asyncio].

Source code in src/jinpy_utils/cache/backends.py 
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class RedisCacheBackend(BaseBackend):
    """Async Redis backend. Requires redis-py[asyncio]."""

    def __init__(self, config: RedisCacheConfig) -> None:
        if aioredis is None:  # pragma: no cover
            raise CacheConnectionError(
                message="redis.asyncio is not available. Install 'redis>=4.2' package.",
                backend_name=config.name,
                backend_type=CacheBackendType.REDIS.value,
            )
        ser = default_serializer(config.serializer)
        super().__init__(config.name, ser, config.default_ttl)
        self._url = config.url
        self._decode = config.decode_responses
        self._pool_size = config.pool_size
        self._connect_timeout = config.connect_timeout
        self._command_timeout = config.command_timeout
        self._client: aioredis.Redis | None = None

    async def _client_or_connect(self) -> aioredis.Redis:
        if self._client is not None:
            return self._client
        try:
            self._client = aioredis.from_url(
                self._url,
                encoding="utf-8" if self._decode else None,
                decode_responses=self._decode,
                max_connections=self._pool_size,
                socket_connect_timeout=self._connect_timeout,
                socket_timeout=self._command_timeout,
            )
            # simple ping
            await self._client.ping()
            return self._client
        except Exception as e:
            raise CacheConnectionError(
                message=f"Redis connection failed: {e}",
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aget(self, key: str) -> Any | None:
        k = normalize_key(key)
        cli = await self._client_or_connect()
        try:
            data = await cli.get(k)
            if data is None:
                return None
            raw = data.encode("utf-8") if self._decode else data
            return self._de(raw)
        except CacheException:
            raise
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis GET failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aset(self, key: str, value: Any, ttl: float | None = None) -> None:
        k = normalize_key(key)
        cli = await self._client_or_connect()
        try:
            raw = self._ser(value)
            if self._decode:
                # store text when decode_responses is True
                await cli.set(
                    k,
                    raw.decode("utf-8"),
                    ex=cast("None", ttl if ttl else self._default_ttl),
                )
            else:
                await cli.set(
                    k, raw, ex=cast("None", ttl if ttl else self._default_ttl)
                )
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis SET failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def adelete(self, key: str) -> None:
        k = normalize_key(key)
        cli = await self._client_or_connect()
        try:
            await cli.delete(k)
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis DEL failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aexists(self, key: str) -> bool:
        k = normalize_key(key)
        cli = await self._client_or_connect()
        try:
            return bool(await cli.exists(k))
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis EXISTS failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aclear(self) -> None:
        cli = await self._client_or_connect()
        try:
            # Use scan+delete to avoid flushing entire DB
            cursor: int = 0
            while True:
                cursor, keys = await cli.scan(cursor=cursor, match="*")
                if keys:
                    await cli.delete(*keys)
                if cursor == 0:
                    break
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis CLEAR failed: {e}",
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aget_many(self, keys: list[str]) -> dict[str, Any | None]:
        cli = await self._client_or_connect()
        nkeys = [normalize_key(k) for k in keys]
        try:
            values = await cli.mget(nkeys)
            result: dict[str, Any | None] = {}
            for k, v in zip(keys, values, strict=False):
                if v is None:
                    result[k] = None
                else:
                    raw = v.encode("utf-8") if self._decode else v
                    result[k] = self._de(raw)
            return result
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis MGET failed: {e}",
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aset_many(
        self, items: Mapping[str, Any], ttl: float | None = None
    ) -> None:
        cli = await self._client_or_connect()
        try:
            pipe = cli.pipeline()
            for k, v in items.items():
                nk = normalize_key(k)
                raw = self._ser(v)
                if self._decode:
                    pipe.set(
                        nk,
                        raw.decode("utf-8"),
                        ex=cast("None", ttl if ttl else self._default_ttl),
                    )
                else:
                    pipe.set(
                        nk, raw, ex=cast("None", ttl if ttl else self._default_ttl)
                    )
            await pipe.execute()
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis MSET failed: {e}",
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def adelete_many(self, keys: list[str]) -> None:
        cli = await self._client_or_connect()
        nkeys = [normalize_key(k) for k in keys]
        try:
            if nkeys:
                await cli.delete(*nkeys)
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis DEL MANY failed: {e}",
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def aincr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        if amount < 0:
            raise CacheKeyError(
                "Amount must be non-negative",
                cache_key=key,
                backend_name=self.name,
                operation=CacheOperation.INCR,
            )
        cli = await self._client_or_connect()
        k = normalize_key(key)
        try:
            val = await cli.incrby(k, amount)
            if ttl is not None or self._default_ttl is not None:
                await cli.expire(
                    k, int(ttl if ttl is not None else self._default_ttl or 0)
                )
            return int(val)
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis INCR failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def adecr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        if amount < 0:
            raise CacheKeyError(
                "Amount must be non-negative",
                cache_key=key,
                backend_name=self.name,
                operation=CacheOperation.DECR,
            )
        cli = await self._client_or_connect()
        k = normalize_key(key)
        try:
            val = await cli.decrby(k, amount)
            if ttl is not None or self._default_ttl is not None:
                await cli.expire(
                    k, int(ttl if ttl is not None else self._default_ttl or 0)
                )
            return int(val)
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis DECR failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def attl(self, key: str) -> float | None:
        cli = await self._client_or_connect()
        k = normalize_key(key)
        try:
            t = await cli.ttl(k)
            if t is None or t < 0:
                return None
            return float(t)
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis TTL failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def atouch(self, key: str, ttl: float) -> None:
        cli = await self._client_or_connect()
        k = normalize_key(key)
        try:
            await cli.expire(k, int(ttl))
        except Exception as e:
            raise CacheBackendError(
                message=f"Redis TOUCH failed: {e}",
                cache_key=k,
                backend_name=self.name,
                backend_type=CacheBackendType.REDIS.value,
            ) from e

    async def ais_healthy(self) -> bool:
        try:
            cli = await self._client_or_connect()
            pong = await cli.ping()
            return bool(pong)
        except Exception:
            return False

    async def aclose(self) -> None:
        if self._client is not None:
            try:
                await self._client.aclose()
            finally:
                self._client = None

Functions

__init__ 

__init__(config: RedisCacheConfig) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def __init__(self, config: RedisCacheConfig) -> None:
    if aioredis is None:  # pragma: no cover
        raise CacheConnectionError(
            message="redis.asyncio is not available. Install 'redis>=4.2' package.",
            backend_name=config.name,
            backend_type=CacheBackendType.REDIS.value,
        )
    ser = default_serializer(config.serializer)
    super().__init__(config.name, ser, config.default_ttl)
    self._url = config.url
    self._decode = config.decode_responses
    self._pool_size = config.pool_size
    self._connect_timeout = config.connect_timeout
    self._command_timeout = config.command_timeout
    self._client: aioredis.Redis | None = None

File Backend

FileCacheBackend

FileCacheBackend

Bases: BaseBackend

Simple file-based backend storing entries per file.

Source code in src/jinpy_utils/cache/backends.py 
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class FileCacheBackend(BaseBackend):
    """Simple file-based backend storing entries per file."""

    def __init__(self, config: FileCacheConfig) -> None:
        ser = default_serializer(config.serializer)
        super().__init__(config.name, ser, config.default_ttl)
        self._dir = config.directory
        self._ext = config.file_extension
        self._max_entries = config.max_entries
        self._lock = asyncio.Lock()

    def _path_for(self, key: str) -> Path:
        safe = hashlib.sha256(key.encode("utf-8")).hexdigest()
        return self._dir / f"{safe}{self._ext}"

    async def aget(self, key: str) -> Any | None:
        async with self._lock:
            p = self._path_for(normalize_key(key))
            if not p.exists():
                return None
            try:
                data = p.read_bytes()
                ttl_bytes = p.with_suffix(p.suffix + ".ttl")
                expiry: float | None = None
                if ttl_bytes.exists():
                    try:
                        expiry = float(ttl_bytes.read_text())
                    except Exception:
                        expiry = None
                if expiry is not None and remaining_ttl(expiry) == 0:
                    p.unlink(missing_ok=True)
                    ttl_bytes.unlink(missing_ok=True)
                    return None
                return self._de(data)
            except Exception as e:
                raise CacheBackendError(
                    message=f"File GET failed: {e}",
                    cache_key=key,
                    backend_name=self.name,
                    backend_type=CacheBackendType.FILE.value,
                ) from e

    async def aset(self, key: str, value: Any, ttl: float | None = None) -> None:
        async with self._lock:
            p = self._path_for(normalize_key(key))
            try:
                raw = self._ser(value)
                p.write_bytes(raw)
                ex = compute_expiry(
                    ttl if ttl is not None else self._default_ttl,
                )
                ttl_file = p.with_suffix(p.suffix + ".ttl")
                if ex is None:
                    ttl_file.unlink(missing_ok=True)
                else:
                    ttl_file.write_text(str(ex))
                if self._max_entries is not None:
                    # naive eviction: if too many files, remove oldest
                    files = sorted(
                        (f for f in self._dir.glob(f"*{self._ext}")),
                        key=lambda f: f.stat().st_mtime,
                    )
                    while len(files) > self._max_entries:
                        victim = files.pop(0)
                        victim.unlink(missing_ok=True)
                        tf = victim.with_suffix(victim.suffix + ".ttl")
                        tf.unlink(missing_ok=True)
            except Exception as e:
                raise CacheBackendError(
                    message=f"File SET failed: {e}",
                    cache_key=key,
                    backend_name=self.name,
                    backend_type=CacheBackendType.FILE.value,
                ) from e

    async def adelete(self, key: str) -> None:
        async with self._lock:
            p = self._path_for(normalize_key(key))
            try:
                p.unlink(missing_ok=True)
                p.with_suffix(p.suffix + ".ttl").unlink(missing_ok=True)
            except Exception as e:
                raise CacheBackendError(
                    message=f"File DEL failed: {e}",
                    cache_key=key,
                    backend_name=self.name,
                    backend_type=CacheBackendType.FILE.value,
                ) from e

    async def aexists(self, key: str) -> bool:
        async with self._lock:
            p = self._path_for(normalize_key(key))
            if not p.exists():
                return False
            ttl_file = p.with_suffix(p.suffix + ".ttl")
            expiry: float | None = None
            if ttl_file.exists():
                try:
                    expiry = float(ttl_file.read_text())
                except Exception:
                    expiry = None
            if expiry is not None and remaining_ttl(expiry) == 0:
                p.unlink(missing_ok=True)
                ttl_file.unlink(missing_ok=True)
                return False
            return True

    async def aclear(self) -> None:
        async with self._lock:
            for f in self._dir.glob(f"*{self._ext}"):
                try:
                    f.unlink(missing_ok=True)
                    f.with_suffix(f.suffix + ".ttl").unlink(missing_ok=True)
                except Exception:
                    # best-effort clear
                    pass

    async def aget_many(self, keys: list[str]) -> dict[str, Any | None]:
        result: dict[str, Any | None] = {}
        for k in keys:
            result[k] = await self.aget(k)
        return result

    async def aset_many(
        self, items: Mapping[str, Any], ttl: float | None = None
    ) -> None:
        for k, v in items.items():
            await self.aset(k, v, ttl)

    async def adelete_many(self, keys: list[str]) -> None:
        for k in keys:
            await self.adelete(k)

    async def aincr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        if amount < 0:
            raise CacheKeyError(
                "Amount must be non-negative",
                cache_key=key,
                backend_name=self.name,
                operation=CacheOperation.INCR,
            )
        val = await self.aget(key)
        new_val = (int(val) if val is not None else 0) + amount
        await self.aset(key, new_val, ttl)
        return new_val

    async def adecr(self, key: str, amount: int = 1, ttl: float | None = None) -> int:
        if amount < 0:
            raise CacheKeyError(
                "Amount must be non-negative",
                cache_key=key,
                backend_name=self.name,
                operation=CacheOperation.DECR,
            )
        val = await self.aget(key)
        new_val = (int(val) if val is not None else 0) - amount
        await self.aset(key, new_val, ttl)
        return new_val

    async def attl(self, key: str) -> float | None:
        async with self._lock:
            p = self._path_for(normalize_key(key))
            ttl_file = p.with_suffix(p.suffix + ".ttl")
            if not ttl_file.exists():
                return None
            try:
                expiry = float(ttl_file.read_text())
                return remaining_ttl(expiry)
            except Exception:
                return None

    async def atouch(self, key: str, ttl: float) -> None:
        async with self._lock:
            p = self._path_for(normalize_key(key))
            if not p.exists():
                return
            p.with_suffix(p.suffix + ".ttl").write_text(str(ttl))

    async def ais_healthy(self) -> bool:
        try:
            tmp = self._dir / ".healthcheck"
            tmp.write_text("ok")
            tmp.unlink(missing_ok=True)
            return True
        except Exception:
            return False

    async def aclose(self) -> None:
        # Nothing to close
        return None

Functions

__init__ 

__init__(config: FileCacheConfig) -> None
Source code in src/jinpy_utils/cache/backends.py 
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def __init__(self, config: FileCacheConfig) -> None:
    ser = default_serializer(config.serializer)
    super().__init__(config.name, ser, config.default_ttl)
    self._dir = config.directory
    self._ext = config.file_extension
    self._max_entries = config.max_entries
    self._lock = asyncio.Lock()

Examples

Memory backend

from jinpy_utils.cache import Cache, MemoryCacheConfig, CacheManagerConfig

config = CacheManagerConfig(backends=[
    MemoryCacheConfig(name="mem", default_ttl=60)
])

cache = Cache(backend="mem")
cache.set("a", 1)
assert cache.get("a") == 1

File backend

from pathlib import Path
from jinpy_utils.cache import Cache, CacheManager, CacheManagerConfig, FileCacheConfig

cfg = CacheManagerConfig(
    default_backend="disk",
    backends=[FileCacheConfig(name="disk", directory=Path(".cache"))]
)
CacheManager(cfg)  # initialize

cache = Cache(backend="disk")
cache.set("report", {"ok": True})

Redis backend

from jinpy_utils.cache import Cache, CacheManager, CacheManagerConfig, RedisCacheConfig

cfg = CacheManagerConfig(
    default_backend="redis",
    backends=[
        RedisCacheConfig(
            name="redis",
            url="redis://localhost:6379/0",
            decode_responses=False,
            pool_size=10,
        )
    ]
)
CacheManager(cfg)  # initialize

cache = Cache(backend="redis")
await cache.aset("k", {"v": 1}, ttl=30)
value = await cache.aget("k")