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RedisAdapter

What it is​

  • A Redis-backed implementation of IKeyValueAdapter for basic key/value operations.
  • Stores and returns raw bytes (decode_responses=False) and normalizes returned Redis values into bytes.

Public API​

  • class RedisAdapter(IKeyValueAdapter)
    • __init__(redis_url: str, socket_timeout: Optional[float] = None)
      • Creates a Redis client from a URL.
    • get(key: str) -> bytes
      • Fetches a value by key.
      • Raises KVNotFoundError if the key does not exist.
    • set(key: str, value: bytes, ttl: int | None = None) -> None
      • Sets a key to a value with optional TTL (seconds).
    • set_if_not_exists(key: str, value: bytes, ttl: int | None = None) -> bool
      • Sets a key only if it does not already exist; returns True if set.
    • delete(key: str) -> None
      • Deletes a key.
      • Raises KVNotFoundError if the key does not exist.
    • delete_if_value_matches(key: str, value: bytes) -> bool
      • Atomically deletes a key only if its current value matches; returns True if deleted.
    • exists(key: str) -> bool
      • Checks if a key exists.

Configuration/Dependencies​

  • Requires the redis Python package:
    • Install: pip install redis
  • Constructor parameters:
    • redis_url: required; passed to redis.Redis.from_url(...).
    • socket_timeout: optional float; forwarded to the Redis client.
  • Uses decode_responses=False (values handled as bytes-like, then normalized to bytes).

Usage​

from naas_abi_core.services.keyvalue.adapters.secondary.RedisAdapter import RedisAdapter
from naas_abi_core.services.keyvalue.KeyValuePorts import KVNotFoundError

kv = RedisAdapter(redis_url="redis://localhost:6379/0")

kv.set("k1", b"v1", ttl=60)
assert kv.get("k1") == b"v1"

created = kv.set_if_not_exists("k1", b"v2")
assert created is False

deleted = kv.delete_if_value_matches("k1", b"v1")
assert deleted is True
assert kv.exists("k1") is False

try:
    kv.get("k1")
except KVNotFoundError:
    pass

Caveats​

  • get() and delete() raise KVNotFoundError when the key is missing.
  • Values are normalized to bytes; passing str, bytearray, or memoryview is accepted internally via normalization.