Update to langgraph 0.2 compatibility

README.md

@@ -1,4 +1,4 @@
-# AI Agent Service Toolkit
+# 🧰 AI Agent Service Toolkit
 
 This repository provides a blueprint and full toolkit for a LangGraph-based agent service architecture. It includes a [LangGraph](https://langchain-ai.github.io/langgraph/) agent, a [FastAPI](https://fastapi.tiangolo.com/) service to serve it, a client to interact with the service, and a [Streamlit](https://streamlit.io/) app that uses the client to provide a chat interface.
 

agent/research_assistant.py

@@ -5,7 +5,7 @@
 from langchain_core.language_models.chat_models import BaseChatModel
 from langchain_core.messages import AIMessage, SystemMessage, RemoveMessage
 from langchain_core.runnables import RunnableConfig, RunnableLambda
-from langgraph.checkpoint import MemorySaver
+from langgraph.checkpoint.memory import MemorySaver
 from langgraph.graph import END, StateGraph, MessagesState
 from langgraph.managed import IsLastStep
 from langgraph.prebuilt import ToolNode

requirements.txt

@@ -5,15 +5,16 @@
 # IMPORTANT: This also requires using python < 3.12.4
 
 aiohttp~=3.10.0
-aiosqlite~=0.20.0
 arxiv~=2.1.3
 duckduckgo-search~=6.2.6
 fastapi<0.100.0
 langchain-core~=0.2.26
 langchain-community~=0.2.11
 langchain-openai~=0.1.20
 langchain-groq~=0.1.9
-langgraph==0.1.19
+langgraph~=0.2.3
+langgraph-checkpoint~=1.0.2
+langgraph-checkpoint-sqlite~=1.0.0
 langsmith~=0.1.96
 numexpr~=2.10.1
 pydantic~=1.10.17

service/service.py

@@ -8,7 +8,7 @@
 from fastapi.responses import StreamingResponse
 from langchain_core.callbacks import AsyncCallbackHandler
 from langchain_core.runnables import RunnableConfig
-from langgraph.checkpoint.aiosqlite import AsyncSqliteSaver
+from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver
 from langgraph.graph.graph import CompiledGraph
 from langsmith import Client as LangsmithClient