Files
jbod-monitor/services/cache.py

63 lines
1.7 KiB
Python

import json
import logging
import os
from typing import Any
import redis.asyncio as redis
logger = logging.getLogger(__name__)
_redis: redis.Redis | None = None
async def init_cache() -> None:
"""Create Redis connection from environment variables."""
global _redis
host = os.environ.get("REDIS_HOST", "localhost")
port = int(os.environ.get("REDIS_PORT", "6379"))
db = int(os.environ.get("REDIS_DB", "0"))
try:
_redis = redis.Redis(host=host, port=port, db=db, decode_responses=True)
await _redis.ping()
logger.info("Redis connected at %s:%d/%d", host, port, db)
except Exception as e:
logger.warning("Redis connection failed: %s — running without cache", e)
_redis = None
async def close_cache() -> None:
"""Close Redis connection."""
global _redis
if _redis is not None:
await _redis.aclose()
_redis = None
def redis_available() -> bool:
"""Return whether Redis connection is live."""
return _redis is not None
async def cache_get(key: str) -> Any | None:
"""GET key from Redis, return deserialized value or None on miss/error."""
if _redis is None:
return None
try:
raw = await _redis.get(key)
if raw is None:
return None
return json.loads(raw)
except Exception as e:
logger.warning("Redis GET %s failed: %s", key, e)
return None
async def cache_set(key: str, value: Any, ttl: int = 120) -> None:
"""SET key in Redis with expiry, silently catches errors."""
if _redis is None:
return
try:
await _redis.set(key, json.dumps(value), ex=ttl)
except Exception as e:
logger.warning("Redis SET %s failed: %s", key, e)