基于 Redis 的聊天记忆
为了在多个聊天会话中实现更长期的持久化存储,您可以将 BufferMemory 等聊天记忆类默认使用的内存中 chatHistory 替换为 Redis 实例。
环境准备
您需要在项目中安装 node-redis:
:::提示 请参阅安装集成包的一般说明部分。 :::
- npm
- Yarn
- pnpm
npm install @langchain/openai @langchain/community @langchain/core redis
yarn add @langchain/openai @langchain/community @langchain/core redis
pnpm add @langchain/openai @langchain/community @langchain/core redis
同时,您还需要一个可以连接的 Redis 实例。关于如何在本地运行 Redis 服务器,请参阅 Redis 官方网站 上的说明。
使用方法
存储在 Redis 中的每个聊天历史会话都必须具有唯一的 ID。您还可以提供可选的 sessionTTL 参数,用于设置会话在指定秒数后自动过期。
config 参数将直接传递给 node-redis 的 createClient 方法,支持其所有相同的参数。
import { BufferMemory } from "langchain/memory";
import { RedisChatMessageHistory } from "@langchain/redis";
import { ChatOpenAI } from "@langchain/openai";
import { ConversationChain } from "langchain/chains";
const memory = new BufferMemory({
chatHistory: new RedisChatMessageHistory({
sessionId: new Date().toISOString(), // Or some other unique identifier for the conversation
sessionTTL: 300, // 5 minutes, omit this parameter to make sessions never expire
}),
});
const model = new ChatOpenAI({
model: "gpt-3.5-turbo",
temperature: 0,
});
const chain = new ConversationChain({ llm: model, memory });
const res1 = await chain.invoke({ input: "Hi! I'm Jim." });
console.log({ res1 });
/*
{
res1: {
text: "Hello Jim! It's nice to meet you. My name is AI. How may I assist you today?"
}
}
*/
const res2 = await chain.invoke({ input: "What did I just say my name was?" });
console.log({ res2 });
/*
{
res1: {
text: "You said your name was Jim."
}
}
*/
API Reference:
- BufferMemory from
langchain/memory - RedisChatMessageHistory from
@langchain/redis - ChatOpenAI from
@langchain/openai - ConversationChain from
langchain/chains
高级用法
您也可以直接传入一个先前创建的 node-redis 客户端实例:
import { Redis } from "ioredis";
import { BufferMemory } from "langchain/memory";
import { RedisChatMessageHistory } from "@langchain/community/stores/message/ioredis";
import { ChatOpenAI } from "@langchain/openai";
import { ConversationChain } from "langchain/chains";
const client = new Redis("redis://localhost:6379");
const memory = new BufferMemory({
chatHistory: new RedisChatMessageHistory({
sessionId: new Date().toISOString(),
sessionTTL: 300,
client,
}),
});
const model = new ChatOpenAI({
model: "gpt-3.5-turbo",
temperature: 0,
});
const chain = new ConversationChain({ llm: model, memory });
const res1 = await chain.invoke({ input: "Hi! I'm Jim." });
console.log({ res1 });
/*
{
res1: {
text: "Hello Jim! It's nice to meet you. My name is AI. How may I assist you today?"
}
}
*/
const res2 = await chain.invoke({ input: "What did I just say my name was?" });
console.log({ res2 });
/*
{
res1: {
text: "You said your name was Jim."
}
}
*/
API Reference:
- BufferMemory from
langchain/memory - RedisChatMessageHistory from
@langchain/community/stores/message/ioredis - ChatOpenAI from
@langchain/openai - ConversationChain from
langchain/chains
Redis Sentinel 支持
您可以使用 ioredis 启用基于 Redis Sentinel 的缓存。
这需要在项目中安装 ioredis。
- npm
- Yarn
- pnpm
npm install ioredis
yarn add ioredis
pnpm add ioredis
import { Redis } from "ioredis";
import { BufferMemory } from "langchain/memory";
import { RedisChatMessageHistory } from "@langchain/community/stores/message/ioredis";
import { ChatOpenAI } from "@langchain/openai";
import { ConversationChain } from "langchain/chains";
// Uses ioredis to facilitate Sentinel Connections see their docs for details on setting up more complex Sentinels: https://github.com/redis/ioredis#sentinel
const client = new Redis({
sentinels: [
{ host: "localhost", port: 26379 },
{ host: "localhost", port: 26380 },
],
name: "mymaster",
});
const memory = new BufferMemory({
chatHistory: new RedisChatMessageHistory({
sessionId: new Date().toISOString(),
sessionTTL: 300,
client,
}),
});
const model = new ChatOpenAI({ model: "gpt-4o-mini", temperature: 0.5 });
const chain = new ConversationChain({ llm: model, memory });
const res1 = await chain.invoke({ input: "Hi! I'm Jim." });
console.log({ res1 });
/*
{
res1: {
text: "Hello Jim! It's nice to meet you. My name is AI. How may I assist you today?"
}
}
*/
const res2 = await chain.invoke({ input: "What did I just say my name was?" });
console.log({ res2 });
/*
{
res1: {
text: "You said your name was Jim."
}
}
*/
API Reference:
- BufferMemory from
langchain/memory - RedisChatMessageHistory from
@langchain/community/stores/message/ioredis - ChatOpenAI from
@langchain/openai - ConversationChain from
langchain/chains