fix sqlite_vec by using local thread

llama_stack/providers/inline/vector_io/sqlite_vec/sqlite_vec.py

@@ -8,6 +8,7 @@ import hashlib
 import logging
 import sqlite3
 import struct
+import threading
 import uuid
 from typing import Any, Dict, List, Optional
 
@@ -158,11 +159,21 @@ class SQLiteVecVectorIOAdapter(VectorIO, VectorDBsProtocolPrivate):
         self.config = config
         self.inference_api = inference_api
         self.cache: Dict[str, VectorDBWithIndex] = {}
-        self.connection: Optional[sqlite3.Connection] = None
+        self._local = threading.local()
+
+    def _get_connection(self):
+        """Get a thread-local database connection."""
+        if not hasattr(self._local, "conn"):
+            try:
+                self._local.conn = sqlite3.connect(self.config.db_path)
+            except Exception as e:
+                print(f"Error connecting to SQLite database: {e}")
+                raise e
+        return self._local.conn
 
     async def initialize(self) -> None:
         # Open a connection to the SQLite database (the file is specified in the config).
-        self.connection = sqlite3.connect(self.config.db_path, check_same_thread=False)
+        self.connection = self._get_connection()
         self.connection.enable_load_extension(True)
         sqlite_vec.load(self.connection)
         self.connection.enable_load_extension(False)
@@ -185,9 +196,14 @@ class SQLiteVecVectorIOAdapter(VectorIO, VectorDBsProtocolPrivate):
             self.cache[vector_db.identifier] = VectorDBWithIndex(vector_db, index, self.inference_api)
 
     async def shutdown(self) -> None:
-        if self.connection:
-            self.connection.close()
-            self.connection = None
+        # We can't access other threads' connections, so we just close our own
+        if hasattr(self._local, "conn"):
+            try:
+                self._local.conn.close()
+            except Exception as e:
+                print(f"Error closing SQLite connection: {e}")
+            finally:
+                del self._local.conn
 
     async def register_vector_db(self, vector_db: VectorDB) -> None:
         if self.connection is None: