Files
langgraph/examples/node-retries.ipynb
T

121 lines
3.6 KiB
Plaintext

{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# How to add node retry policies\n",
"\n",
"There are many use cases where you may wish for your node to have a custom retry policy, for example if you are calling an API, querying a database, or calling an LLM, etc. \n",
"\n",
"In order to configure the retry policy, you have to pass the `retry` parameter to the `add_node` function. The `retry` parameter takes in a `RetryPolicy` named tuple object. Below we instantiate a `RetryPolicy` object with the default parameters:"
]
},
{
"cell_type": "code",
"execution_count": 15,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"RetryPolicy(initial_interval=0.5, backoff_factor=2.0, max_interval=128.0, max_attempts=3, jitter=True, retry_on=<function default_retry_on at 0x1157419e0>)"
]
},
"execution_count": 15,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"from langgraph.pregel import RetryPolicy\n",
"\n",
"RetryPolicy()"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"If you want more information on what each of the parameters does, be sure to read the [reference](https://langchain-ai.github.io/langgraph/reference/graphs/#retrypolicy).\n",
"\n",
"## Passing a retry policy to a node\n",
"\n",
"Lastly, we can pass `RetryPolicy` objects when we call the `add_node` function. In the example below we pass two different retry policies to each of our nodes:"
]
},
{
"cell_type": "code",
"execution_count": 21,
"metadata": {},
"outputs": [],
"source": [
"import operator\n",
"import sqlite3\n",
"from typing import Annotated, Sequence, TypedDict\n",
"\n",
"from langchain_anthropic import ChatAnthropic\n",
"from langchain_core.messages import BaseMessage\n",
"\n",
"from langgraph.graph import END, StateGraph, START\n",
"from langchain_community.utilities import SQLDatabase\n",
"from langchain_core.messages import AIMessage\n",
"\n",
"db = SQLDatabase.from_uri(\"sqlite:///:memory:\")\n",
"\n",
"model = ChatAnthropic(model_name=\"claude-2.1\")\n",
"\n",
"\n",
"class AgentState(TypedDict):\n",
" messages: Annotated[Sequence[BaseMessage], operator.add]\n",
"\n",
"\n",
"def query_database(state):\n",
" query_result = db.run(\"SELECT * FROM Artist LIMIT 10;\")\n",
" return {\"messages\": [AIMessage(content=query_result)]}\n",
"\n",
"\n",
"def call_model(state):\n",
" response = model.invoke(state[\"messages\"])\n",
" return {\"messages\": [response]}\n",
"\n",
"\n",
"# Define a new graph\n",
"workflow = StateGraph(AgentState)\n",
"workflow.add_node(\n",
" \"query_database\",\n",
" query_database,\n",
" retry=RetryPolicy(retry_on=sqlite3.OperationalError),\n",
")\n",
"workflow.add_node(\"model\", call_model, retry=RetryPolicy(max_attempts=5))\n",
"workflow.add_edge(START, \"model\")\n",
"workflow.add_edge(\"model\", \"query_database\")\n",
"workflow.add_edge(\"query_database\", END)\n",
"\n",
"app = workflow.compile()"
]
}
],
"metadata": {
"kernelspec": {
"display_name": "env",
"language": "python",
"name": "python3"
},
"language_info": {
"codemirror_mode": {
"name": "ipython",
"version": 3
},
"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.11.9"
}
},
"nbformat": 4,
"nbformat_minor": 2
}