Initial pve cloud backup app

backend/app/db.py

@@ -0,0 +1,37 @@
+import sqlite3
+from contextlib import contextmanager
+from datetime import datetime, timezone
+from typing import Iterator
+
+from .config import DB_PATH, ensure_dirs
+
+
+def utc_now() -> str:
+    return datetime.now(timezone.utc).replace(microsecond=0).isoformat()
+
+
+def connect() -> sqlite3.Connection:
+    ensure_dirs()
+    conn = sqlite3.connect(DB_PATH, timeout=30)
+    conn.row_factory = sqlite3.Row
+    conn.execute("PRAGMA foreign_keys = ON")
+    conn.execute("PRAGMA journal_mode = WAL")
+    conn.execute("PRAGMA busy_timeout = 30000")
+    return conn
+
+
+@contextmanager
+def db() -> Iterator[sqlite3.Connection]:
+    conn = connect()
+    try:
+        yield conn
+        conn.commit()
+    except Exception:
+        conn.rollback()
+        raise
+    finally:
+        conn.close()
+
+
+def row_to_dict(row: sqlite3.Row | None) -> dict | None:
+    return None if row is None else dict(row)