Redis Backend

mongo_ops.cache.redis_backend

Summary

Redis cache backend with key prefixing and pub/sub invalidation.

Classes

RedisCacheBackend

RedisCacheBackend(
    redis_client: Redis,
    key_prefix: str = "",
    default_ttl: int = 300,
)

Bases: CacheBackend

Cache backend backed by Redis with key prefixing.

Values are stored with a configurable key prefix, and deletions publish on a shared invalidation channel so other processes can react.

Notes

Lifecycle:

Requires ``pip install mongo-ops[redis]`` and a live Redis
connection supplied by the caller.

Initialize the backend.

Parameters:

Name	Type	Description	Default
redis_client	Redis	Asynchronous Redis client.	required
key_prefix	str	Prefix applied to all keys. Defaults to "".	''
default_ttl	int	Default time-to-live for entries, in seconds.	300

Raises:

Type	Description
ImportError	If the redis package is not installed.

Functions

clear_pattern async

clear_pattern(pattern: str) -> None

Remove all keys matching a glob pattern via SCAN/DEL.

Parameters:

Name	Type	Description	Default
pattern	str	Glob-style pattern; a trailing * matches prefixes.	required

delete async

delete(key: str) -> None

Remove a key and publish an invalidation notice.

Parameters:

Name	Type	Description	Default
key	str	The cache key.	required

exists async

exists(key: str) -> bool

Check whether a key is present.

Parameters:

Name	Type	Description	Default
key	str	The cache key.	required

Returns:

Name	Type	Description
bool	bool	True if the key exists, False otherwise.

get async

get(key: str) -> bytes | None

Fetch a value from the cache.

Parameters:

Name	Type	Description	Default
key	str	The cache key.	required

Returns:

Type	Description
bytes | None	Optional[bytes]: The cached bytes, or None on a miss.

get_stats async

get_stats() -> CacheStats

Return a snapshot of cache statistics.

Returns:

Name	Type	Description
CacheStats	CacheStats	Stats with current_size taken from Redis dbsize.

initialize async

initialize() -> None

Open the pub/sub subscription used for invalidation.

publish_invalidate async

publish_invalidate(key: str) -> None

Publish an invalidation notice for a key.

Parameters:

Name	Type	Description	Default
key	str	The cache key to broadcast.	required

set async

set(key: str, value: bytes, ttl: int | None = None) -> None

Store a value in the cache.

Parameters:

Name	Type	Description	Default
key	str	The cache key.	required
value	bytes	The byte-encoded value to store.	required
ttl	Optional[int]	Time-to-live in seconds; defaults to the backend default.	None

shutdown async

shutdown() -> None

Close the pub/sub subscription.

Functions

decode_value

decode_value(data: bytes) -> dict

Decode cache bytes back into a dict.

Parameters:

Name	Type	Description	Default
data	bytes	UTF-8 JSON bytes produced by encode_value().	required

Returns:

Name	Type	Description
dict	dict	The decoded dictionary.

encode_value

encode_value(value: dict) -> bytes

Encode a dict into cache-ready bytes.

Non-serializable values (e.g., ObjectId) are coerced with str().

Parameters:

Name	Type	Description	Default
value	dict	The dictionary to encode.	required

Returns:

Name	Type	Description
bytes	bytes	UTF-8 JSON bytes.