CacheRedisAdapter

What it is

• A Redis-backed implementation of ICacheAdapter.
• Stores cache entries as JSON-serialized CachedData in Redis.
• Uses namespaced, hashed Redis keys: {prefix}:{sha256(logical_key)}.

Public API

• class CacheRedisAdapter(ICacheAdapter)
  • __init__(redis_url: str, prefix: str = "naas:cache", socket_timeout: float | None = None)
    • Connects to Redis using redis.Redis.from_url(...).
    • Normalizes prefix by stripping trailing :.
  • get(key: str) -> CachedData
    • Fetches and deserializes a CachedData entry.
    • Raises CacheNotFoundError if missing.
  • set(key: str, value: CachedData) -> None
    • Stores a CachedData entry (JSON).
  • set_if_absent(key: str, value: CachedData) -> bool
    • Atomically sets only if key does not exist (Redis NX).
    • Returns True if set, False otherwise.
  • delete(key: str) -> None
    • Deletes an entry.
    • Raises CacheNotFoundError if missing.
  • exists(key: str) -> bool
    • Checks existence of an entry.

Configuration/Dependencies

• Requires the redis Python package (import redis as redis_lib).
• Redis connection:
  • redis_url: e.g. redis://localhost:6379/0
  • socket_timeout: forwarded to the Redis client
• Uses decode_responses=True (Redis values are returned as str).

Usage

from naas_abi_core.services.cache.adapters.secondary.CacheRedisAdapter import CacheRedisAdapter
from naas_abi_core.services.cache.CachePort import CachedData

cache = CacheRedisAdapter(redis_url="redis://localhost:6379/0", prefix="naas:cache")

key = "user:123"

value = CachedData(...)  # construct per your project's CachedData schema
cache.set(key, value)

if cache.exists(key):
    loaded = cache.get(key)
    print(loaded)

was_set = cache.set_if_absent(key, value)
print("set_if_absent:", was_set)

cache.delete(key)

Caveats

• Redis keys are not the raw logical keys; they are SHA-256 hashes with a prefix. You cannot easily inspect Redis to find entries by logical key without hashing.
• get() and delete() raise CacheNotFoundError when the entry does not exist.