Skip to main content

Momento 支持的聊天内存

¥Momento-Backed Chat Memory

为了在聊天会话中实现分布式、无服务器持久化，你可以换入由 Momento 支持的聊天消息历史记录。由于 Momento 缓存可立即使用且无需任何基础设施维护，因此无论是在本地构建还是在生产环境中，它都是开始使用聊天历史记录的绝佳方式。

¥For distributed, serverless persistence across chat sessions, you can swap in a Momento-backed chat message history. Because a Momento cache is instantly available and requires zero infrastructure maintenance, it's a great way to get started with chat history whether building locally or in production.

设置​

¥Setup

你需要在你的项目中安装 Momento 客户端库。鉴于 Momento 与 Node.js、浏览器和边缘环境的兼容性，请确保你安装了相关的软件包。

¥You will need to install the Momento Client Library in your project. Given Momento's compatibility with Node.js, browser, and edge environments, ensure you install the relevant package.

要为 Node.js 安装：

¥To install for Node.js:

npm install @gomomento/sdk

浏览器/Edge 工作器安装：

¥To install for browser/edge workers:

npm install @gomomento/sdk-web
tip

请参阅 此部分包含有关安装集成包的一般说明。

¥See this section for general instructions on installing integration packages.

npm install @langchain/openai @langchain/community @langchain/core

你还需要一个来自 Momento 的 API 密钥。你可以注册一个免费账户 此处。

¥You will also need an API key from Momento. You can sign up for a free account here.

用法​

¥Usage

为了区分不同的聊天历史记录会话，我们需要一个唯一的 sessionId。你还可以提供可选的 sessionTtl，使会话在指定的秒数后过期。

¥To distinguish one chat history session from another, we need a unique sessionId. You may also provide an optional sessionTtl to make sessions expire after a given number of seconds.

import {
  CacheClient,
  Configurations,
  CredentialProvider,
} from "@gomomento/sdk"; // `from "gomomento/sdk-web";` for browser/edge
import { BufferMemory } from "langchain/memory";
import { ChatOpenAI } from "@langchain/openai";
import { ConversationChain } from "langchain/chains";
import { MomentoChatMessageHistory } from "@langchain/community/stores/message/momento";

// See https://github.com/momentohq/client-sdk-javascript for connection options
const client = new CacheClient({
  configuration: Configurations.Laptop.v1(),
  credentialProvider: CredentialProvider.fromEnvironmentVariable({
    environmentVariableName: "MOMENTO_API_KEY",
  }),
  defaultTtlSeconds: 60 * 60 * 24,
});

// Create a unique session ID
const sessionId = new Date().toISOString();
const cacheName = "langchain";

const memory = new BufferMemory({
  chatHistory: await MomentoChatMessageHistory.fromProps({
    client,
    cacheName,
    sessionId,
    sessionTtl: 300,
  }),
});
console.log(
  `cacheName=${cacheName} and sessionId=${sessionId} . This will be used to store the chat history. You can inspect the values at your Momento console at https://console.gomomento.com.`
);

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."
  }
}
*/

// See the chat history in the Momento
console.log(await memory.chatHistory.getMessages());

API Reference: