Redis¶

Redis is used for bounded, ephemeral state—not as a second vector backend:

pip install "protoprompt[redis]"

PostgreSQL/pgvector remains the production vector retrieval recommendation. Adding Redis Search would introduce another index lifecycle and subtly different filtering semantics without improving the common deployment. Redis instead handles three native strengths.

TTL embedding cache¶

from protoprompt import CachedLLMClient, MemoryScope
from protoprompt.integrations import RedisEmbeddingCache

cache = RedisEmbeddingCache(
    "redis://localhost:6379/0",
    ttl_seconds=3600,
    scope=MemoryScope(tenant="acme", user="alice"),
)
embeddings = CachedLLMClient(model_client, cache)

CachedLLMClient accepts sync and async cache contracts. Redis keys contain only a scope/key hash—never input text or model prompts. Corrupt payloads are deleted and treated as misses.

Ephemeral sessions and profiles¶

RedisSession implements ordered get_items(limit), add_items, pop_item, and clear_session, matching the session semantics used by the OpenAI Agents adapter. Reads and writes refresh TTL.

RedisProfileStore is tenant-pinned and implements optimistic locking with Redis WATCH/MULTI/EXEC. It is appropriate for expiring profiles; use PostgresProfileStore when the profile is a durable system of record.

session = RedisSession(
    "case-42",
    scope=MemoryScope(tenant="acme", user="alice", thread="case-42"),
    url="redis://localhost:6379/0",
    ttl_seconds=86_400,
)
profiles = RedisProfileStore(
    client=session.client,
    tenant="acme",
    ttl_seconds=86_400,
)

Share the Redis client, not its connection pool. Externally supplied clients remain host-owned; URL-created clients must be closed with await close().

Integration and reconnect test¶

docker compose -f docker-compose.redis.yml up -d --wait
export PROTOPROMPT_REDIS_URL="redis://localhost:56379/15"
pytest tests/integration/test_redis_integration.py -v
docker compose -f docker-compose.redis.yml down

The test forces a connection-pool disconnect, verifies transparent reconnect, checks TTL, and races ten profile compare-and-swap operations. Configure timeouts, health checks, retry policy, TLS, and ACL credentials in the host for production deployments.