Update app.py

app.py

@@ -6,9 +6,11 @@ import sqlite3
 import json
 import numpy as np
 import datetime
+
 from langchain.chains import RetrievalQA
 from langchain.llms import OpenAI
 from langchain.schema import Document
+from langchain_core.retrievers import BaseRetriever
 
 # --- CONFIG ---
 DB_PATH = "json_vector.db"
@@ -144,11 +146,14 @@ def query_vector_db(user_query, top_k=5):
         docs.append(Document(page_content=row[4], metadata=meta))
     return docs
 
-# --- LangChain Retriever ---
-class SQLiteVectorRetriever:
+# --- LangChain Retriever (subclassing BaseRetriever per v0.1+) ---
+from langchain_core.retrievers import BaseRetriever
+
+class SQLiteVectorRetriever(BaseRetriever):
     def __init__(self, top_k=5):
         self.top_k = top_k
-    def get_relevant_documents(self, query):
+
+    def _get_relevant_documents(self, query, run_manager=None, **kwargs):
         return query_vector_db(query, self.top_k)
 
 llm = OpenAI(model="gpt-4.1", openai_api_key=OPENAI_API_KEY, temperature=0)