ducklm/app/state/checkpoint_store.py

76 lines
2.5 KiB
Python

from __future__ import annotations
import json
import sqlite3
from pathlib import Path
from app.core.contracts import TaskCheckpoint
class SQLiteCheckpointStore:
"""Durable checkpoint store for resumable runtime state."""
def __init__(self, db_path: str | Path) -> None:
self._db_path = Path(db_path)
self._db_path.parent.mkdir(parents=True, exist_ok=True)
self._initialize()
def save(self, checkpoint: TaskCheckpoint) -> TaskCheckpoint:
with sqlite3.connect(self._db_path) as conn:
conn.execute(
"""
INSERT OR REPLACE INTO checkpoints (
task_id, status, active_step_id, plan_snapshot_json,
context_snapshot_json, updated_at
) VALUES (?, ?, ?, ?, ?, ?)
""",
(
checkpoint.task_id,
checkpoint.status,
checkpoint.active_step_id,
json.dumps(checkpoint.plan_snapshot, default=str),
json.dumps(checkpoint.context_snapshot, default=str),
checkpoint.updated_at.isoformat(),
),
)
conn.commit()
return checkpoint
def load(self, task_id: str) -> TaskCheckpoint | None:
with sqlite3.connect(self._db_path) as conn:
row = conn.execute(
"""
SELECT task_id, status, active_step_id, plan_snapshot_json,
context_snapshot_json, updated_at
FROM checkpoints
WHERE task_id = ?
""",
(task_id,),
).fetchone()
if not row:
return None
return TaskCheckpoint(
task_id=row[0],
status=row[1],
active_step_id=row[2],
plan_snapshot=json.loads(row[3]),
context_snapshot=json.loads(row[4]),
updated_at=row[5],
)
def _initialize(self) -> None:
with sqlite3.connect(self._db_path) as conn:
conn.execute(
"""
CREATE TABLE IF NOT EXISTS checkpoints (
task_id TEXT PRIMARY KEY,
status TEXT NOT NULL,
active_step_id TEXT,
plan_snapshot_json TEXT NOT NULL,
context_snapshot_json TEXT NOT NULL,
updated_at TEXT NOT NULL
)
"""
)
conn.commit()