Configuration reference¶

All options live on CacheConfig. Every field can also be set from an environment variable (read by MemoryCache.from_env()) where noted.

Field	Type / accepted values	Default	Env var	Description
`backend`	`"memory"` \| `"redis"`	`"memory"`	`MEMORY_REUSE_BACKEND`	Storage backend. `redis` needs the `[redis]` extra.
`redis_url`	`str` \| `None`	`None`	`MEMORY_REUSE_REDIS_URL`	Redis connection URL. Required when `backend="redis"`.
`default_ttl`	`int > 0` \| `None`	`3600`	`MEMORY_REUSE_DEFAULT_TTL` (int or `"none"`)	Default entry TTL in seconds. `None` never expires.
`default_scope`	`"global"` \| `"user"` \| `"session"`	`"global"`	`MEMORY_REUSE_DEFAULT_SCOPE`	Scope used when none is passed explicitly.
`key_prefix`	`str`	`"memreuse"`	`MEMORY_REUSE_KEY_PREFIX`	Prefix prepended to every cache key.
`max_key_size`	`int > 0`	`512`	—	Max cache-key length in bytes.
`enable_stats`	`bool`	`True`	`MEMORY_REUSE_ENABLE_STATS` (`true`/`false`)	Track hit/miss/error counters.
`semantic_enabled`	`bool`	`False`	`MEMORY_REUSE_SEMANTIC_ENABLED` (`true`/`false`)	Turn on the semantic cache. Requires `embedding_provider`.
`similarity_threshold`	`float` in `[0.0, 1.0]`	`0.95`	`MEMORY_REUSE_SIMILARITY_THRESHOLD`	Minimum similarity to count as a match. Higher = stricter.
`embedding_provider`	`"openai"` \| `"local"` \| `"litellm"` \| `None`	`None`	`MEMORY_REUSE_EMBEDDING_PROVIDER`	Which embedding backend to use. Required when `semantic_enabled=True`.
`embedding_model`	`str` \| `None`	`None` (provider default)	`MEMORY_REUSE_EMBEDDING_MODEL`	Model name passed to the provider.
`max_vectors_per_namespace`	`int > 0`	`10000`	—	Per-scope vector cap before LRU eviction.
`store_exact_on_semantic_hit`	`bool`	`True`	—	On a semantic hit, also write an exact entry so the next identical request takes the faster exact path.
`extract_answer`	`bool`	`False`	—	Return only the best-matching sentence(s) of a string answer on a semantic hit (extractive, no LLM).
`extract_min_similarity`	`float` in `[0.0, 1.0]`	`0.5`	—	Confidence a sentence needs before `extract_answer` returns it instead of the full answer.

Validation¶

Invalid values raise at construction time:

an out-of-range similarity_threshold or extract_min_similarity raises ConfigurationError;
a non-positive default_ttl raises InvalidTTLError;
enabling semantic_enabled without an embedding_provider raises ConfigurationError.

From environment¶

from memory_reuse import MemoryCache, CacheConfig

# Build a config purely from MEMORY_REUSE_* variables:
config = CacheConfig.from_env()
cache = MemoryCache(config)

# Or in one step:
cache = MemoryCache.from_env()