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12496fc | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 | """Local SQLite memory; lexical retrieval with explicit provenance and expiry."""
from pathlib import Path
import json
import math
import re
import sqlite3
import time
import uuid
class Memory:
def __init__(self, path):
self.db = sqlite3.connect(str(path))
self.db.execute("CREATE TABLE IF NOT EXISTS memory (id TEXT PRIMARY KEY, layer TEXT, text TEXT, source TEXT, confidence REAL, created REAL, expires REAL, provenance TEXT)")
def put(self, text, source, confidence=1.0, layer="L2", ttl_seconds=None, provenance=None, record_id=None):
if not text or not source or not math.isfinite(confidence) or not 0 <= confidence <= 1 or layer not in {f"L{i}" for i in range(6)}:
raise ValueError("Memory requires text, source, valid confidence and layer")
if ttl_seconds is not None and (not math.isfinite(ttl_seconds) or ttl_seconds <= 0):
raise ValueError("TTL must be positive")
rid, now = record_id or uuid.uuid4().hex, time.time()
self.db.execute("INSERT OR REPLACE INTO memory VALUES (?,?,?,?,?,?,?,?)", (rid, layer, text, source, confidence, now, None if ttl_seconds is None else now + ttl_seconds, json.dumps(provenance or {})))
self.db.commit()
return rid
def retrieve(self, query, limit=5, min_confidence=0.5):
terms = set(re.findall(r"\w+", query.lower()))
self.db.row_factory = sqlite3.Row
rows = self.db.execute("SELECT * FROM memory WHERE (expires IS NULL OR expires>?) AND confidence>=?", (time.time(), min_confidence)).fetchall()
scored = [(len(terms & set(re.findall(r"\w+", r["text"].lower()))), dict(r)) for r in rows]
return [r for score, r in sorted(scored, key=lambda x: (x[0], x[1]["created"]), reverse=True) if score > 0][:max(0, limit)]
def delete(self, record_id):
self.db.execute("DELETE FROM memory WHERE id=?", (record_id,))
self.db.commit()
def expire(self):
self.db.execute("DELETE FROM memory WHERE expires<=?", (time.time(),))
self.db.commit()
def close(self):
self.db.close()
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