fix: reusable sqlite connection

src/uipath_llamaindex/runtime/_sqlite.py

@@ -0,0 +1,190 @@
+"""Async SQLite connection manager with automatic serialization."""
+
+from __future__ import annotations
+
+import asyncio
+from collections.abc import Iterable
+from contextlib import asynccontextmanager
+from sqlite3 import Row
+from typing import Any, AsyncIterator
+
+import aiosqlite
+
+
+class AsyncSqlite:
+    """Async SQLite wrapper with automatic serialization via locks.
+
+    Provides thread-safe access to a SQLite database using asyncio locks
+    to serialize operations. Maintains a single connection and ensures
+    proper WAL mode configuration.
+    """
+
+    def __init__(self, db_path: str, timeout: float = 30.0):
+        """
+        Initialize AsyncSQLite manager.
+
+        Args:
+            db_path: Path to the SQLite database file
+            timeout: Database connection timeout in seconds
+        """
+        self.db_path = db_path
+        self.timeout = timeout
+        self.conn: aiosqlite.Connection | None = None
+        self.lock = asyncio.Lock()
+        self.is_setup = False
+
+    async def __aenter__(self) -> AsyncSqlite:
+        """Async context manager entry."""
+        await self.connect()
+        return self
+
+    async def __aexit__(self, *args) -> None:
+        """Async context manager exit."""
+        await self.close()
+
+    async def connect(self) -> None:
+        """Establish database connection and apply initial pragmas."""
+        if self.conn is not None:
+            return
+
+        self.conn = await aiosqlite.connect(self.db_path, timeout=self.timeout)
+        await self._apply_connection_pragmas()
+
+        # WAL mode is persistent, set once
+        await self.conn.execute("PRAGMA journal_mode=WAL")
+        await self.conn.commit()
+
+    async def close(self) -> None:
+        """Close database connection."""
+        if self.conn:
+            await self.conn.close()
+            self.conn = None
+            self.is_setup = False
+
+    async def execute(
+        self, query: str, parameters: tuple[Any, ...] | None = None
+    ) -> aiosqlite.Cursor:
+        """
+        Execute a single query with automatic locking.
+
+        Args:
+            query: SQL query to execute
+            parameters: Query parameters
+
+        Returns:
+            Cursor with query results
+        """
+        if self.conn is None:
+            await self.connect()
+
+        assert self.conn is not None
+
+        async with self.lock:
+            return await self.conn.execute(query, parameters or ())
+
+    async def executemany(
+        self, query: str, parameters_list: list[tuple[Any, ...]]
+    ) -> None:
+        """
+        Execute a query multiple times with different parameters.
+
+        Args:
+            query: SQL query to execute
+            parameters_list: List of parameter tuples
+        """
+        if self.conn is None:
+            await self.connect()
+
+        assert self.conn is not None
+
+        async with self.lock:
+            await self.conn.executemany(query, parameters_list)
+            await self.conn.commit()
+
+    async def executescript(self, script: str) -> None:
+        """
+        Execute a SQL script (multiple statements).
+
+        Args:
+            script: SQL script to execute
+        """
+        if self.conn is None:
+            await self.connect()
+
+        assert self.conn is not None
+
+        async with self.lock:
+            await self.conn.executescript(script)
+            await self.conn.commit()
+
+    async def commit(self) -> None:
+        """Commit the current transaction."""
+        if self.conn is None:
+            return
+
+        assert self.conn is not None
+
+        async with self.lock:
+            await self.conn.commit()
+
+    @asynccontextmanager
+    async def cursor(self) -> AsyncIterator[aiosqlite.Cursor]:
+        """
+        Get a cursor with automatic locking.
+
+        Yields:
+            Database cursor
+        """
+        if self.conn is None:
+            await self.connect()
+
+        assert self.conn is not None
+
+        async with self.lock:
+            cursor = await self.conn.cursor()
+            try:
+                yield cursor
+            finally:
+                await cursor.close()
+
+    async def fetchone(
+        self, query: str, parameters: tuple[Any, ...] | None = None
+    ) -> Row | None:
+        """
+        Execute query and fetch one result.
+
+        Args:
+            query: SQL query to execute
+            parameters: Query parameters
+
+        Returns:
+            Single row or None
+        """
+        cursor = await self.execute(query, parameters)
+        return await cursor.fetchone()
+
+    async def fetchall(
+        self, query: str, parameters: tuple[Any, ...] | None = None
+    ) -> Iterable[Row]:
+        """
+        Execute query and fetch all results.
+
+        Args:
+            query: SQL query to execute
+            parameters: Query parameters
+
+        Returns:
+            List of rows
+        """
+        cursor = await self.execute(query, parameters)
+        return await cursor.fetchall()
+
+    async def _apply_connection_pragmas(self) -> None:
+        """Apply per-connection PRAGMA settings for optimal concurrency."""
+        if self.conn is None:
+            return
+
+        await self.conn.execute(f"PRAGMA busy_timeout={int(self.timeout * 1000)}")
+        await self.conn.execute("PRAGMA synchronous=NORMAL")
+        await self.conn.execute("PRAGMA cache_size=10000")
+        await self.conn.execute("PRAGMA temp_store=MEMORY")

src/uipath_llamaindex/runtime/factory.py

@@ -26,7 +26,7 @@
     UiPathLlamaIndexRuntimeError,
 )
 from uipath_llamaindex.runtime.runtime import UiPathLlamaIndexRuntime
-from uipath_llamaindex.runtime.storage import SQLiteResumableStorage
+from uipath_llamaindex.runtime.storage import SqliteResumableStorage
 from uipath_llamaindex.runtime.workflow import LlamaIndexWorkflowLoader
 
 
@@ -51,7 +51,7 @@ def __init__(
         self._workflow_lock = asyncio.Lock()
 
         self._storage_lock = asyncio.Lock()
-        self._storage: SQLiteResumableStorage | None = None
+        self._storage: SqliteResumableStorage | None = None
 
         self._setup_instrumentation(self.context.trace_manager)
 
@@ -80,7 +80,7 @@ def _get_storage_path(self) -> str:
         os.makedirs(os.path.dirname(default_path), exist_ok=True)
         return default_path
 
-    async def _get_storage(self) -> SQLiteResumableStorage:
+    async def _get_storage(self) -> SqliteResumableStorage:
         """Get or create the shared storage instance."""
         if self._storage is not None:
             return self._storage
@@ -90,7 +90,7 @@ async def _get_storage(self) -> SQLiteResumableStorage:
                 return self._storage
 
             storage_path = self._get_storage_path()
-            self._storage = SQLiteResumableStorage(storage_path)
+            self._storage = SqliteResumableStorage(storage_path)
             await self._storage.setup()
             return self._storage
 
@@ -291,3 +291,7 @@ async def dispose(self) -> None:
 
         self._workflow_loaders.clear()
         self._workflow_cache.clear()
+
+        if self._storage:
+            await self._storage.dispose()
+            self._storage = None

src/uipath_llamaindex/runtime/runtime.py

@@ -47,7 +47,7 @@
     UiPathLlamaIndexRuntimeError,
 )
 from uipath_llamaindex.runtime.schema import get_entrypoints_schema, get_workflow_schema
-from uipath_llamaindex.runtime.storage import SQLiteResumableStorage
+from uipath_llamaindex.runtime.storage import SqliteResumableStorage
 
 from ._serialize import serialize_output
 
@@ -62,7 +62,7 @@ def __init__(
         workflow: Workflow,
         runtime_id: str | None = None,
         entrypoint: str | None = None,
-        storage: SQLiteResumableStorage | None = None,
+        storage: SqliteResumableStorage | None = None,
         debug_mode: bool = False,
     ):
         """
@@ -76,7 +76,7 @@ def __init__(
         self.workflow: Workflow = workflow
         self.runtime_id: str = runtime_id or "default"
         self.entrypoint: str | None = entrypoint
-        self.storage: SQLiteResumableStorage | None = storage
+        self.storage: SqliteResumableStorage | None = storage
         self.debug_mode: bool = debug_mode
         self._context: Context | None = None