Message Persistence
Open your coding agent in your project's folder, or in an empty folder for a new app.This runs in a coding agent on your computer.
To learn about how to load previous messages and agent states, check out the Loading Message History and Loading Agent State pages.
To persist LangGraph messages to a database, you can use either AsyncPostgresSaver or AsyncSqliteSaver. Set up the asynchronous memory by configuring the graph within a lifespan function, as follows:
from fastapi import FastAPI
from contextlib import asynccontextmanager
from langgraph.checkpoint.postgres.aio import AsyncPostgresSaver
from copilotkit import LangGraphAGUIAgent
from ag_ui_langgraph import add_langgraph_fastapi_endpoint
graph = None
@asynccontextmanager
async def lifespan(app: FastAPI):
async with AsyncPostgresSaver.from_conn_string(
"postgresql://postgres:postgres@127.0.0.1:5432/postgres"
) as checkpointer:
# NOTE: you need to call .setup() the first time you're using your checkpointer
await checkpointer.setup()
# Create an async graph
graph = workflow.compile(checkpointer=checkpointer)
yield
# Create SDK with the graph
app = FastAPI(lifespan=lifespan)
add_langgraph_fastapi_endpoint(
app=app,
agent=LangGraphAGUIAgent(
name="research_agent",
description="Research agent.",
graph=graph,
),
path="/agents/research_agent"
)
To learn more about persistence in LangGraph, check out the LangGraph documentation.