58 lines
1.9 KiB
Python
58 lines
1.9 KiB
Python
"""Search and content caching with LRU eviction."""
|
|
|
|
import hashlib
|
|
import logging
|
|
from datetime import datetime, timedelta
|
|
from pathlib import Path
|
|
from typing import Dict
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
# Cache directories
|
|
CACHE_DIR = Path(__file__).resolve().parent.parent / "cache"
|
|
SEARCH_CACHE_DIR = CACHE_DIR / "search"
|
|
CONTENT_CACHE_DIR = CACHE_DIR / "content"
|
|
CACHE_MAX_ENTRIES = 1000
|
|
|
|
# Create cache directories
|
|
SEARCH_CACHE_DIR.mkdir(parents=True, exist_ok=True)
|
|
CONTENT_CACHE_DIR.mkdir(parents=True, exist_ok=True)
|
|
|
|
# Track cache size for LRU eviction
|
|
search_cache_index: Dict[str, datetime] = {}
|
|
content_cache_index: Dict[str, datetime] = {}
|
|
|
|
# Cache metrics (shared across modules)
|
|
cache_metrics = {"hits": 0, "misses": 0, "evictions": 0}
|
|
|
|
|
|
def generate_cache_key(data: str) -> str:
|
|
"""Generate a unique cache key using SHA-256 hash."""
|
|
return hashlib.sha256(data.encode("utf-8")).hexdigest()
|
|
|
|
|
|
def cleanup_cache(cache_dir: Path, cache_index: Dict[str, datetime], max_age: timedelta):
|
|
"""Remove expired cache entries and enforce LRU policy."""
|
|
current_time = datetime.now()
|
|
files_in_dir = {f.name.split(".")[0]: f for f in cache_dir.glob("*.cache")}
|
|
|
|
to_remove = []
|
|
for key, timestamp in list(cache_index.items()):
|
|
if current_time - timestamp > max_age or key not in files_in_dir:
|
|
to_remove.append(key)
|
|
if key in files_in_dir:
|
|
files_in_dir[key].unlink(missing_ok=True)
|
|
|
|
for key in to_remove:
|
|
cache_index.pop(key, None)
|
|
cache_metrics["evictions"] += 1
|
|
|
|
if len(cache_index) > CACHE_MAX_ENTRIES:
|
|
sorted_items = sorted(cache_index.items(), key=lambda x: x[1])
|
|
excess_count = len(cache_index) - CACHE_MAX_ENTRIES
|
|
for key, _ in sorted_items[:excess_count]:
|
|
cache_index.pop(key, None)
|
|
cache_file = cache_dir / f"{key}.cache"
|
|
cache_file.unlink(missing_ok=True)
|
|
cache_metrics["evictions"] += 1
|