Rockset

Rockset 是一款运行在云端的实时分析 SQL 数据库。Rockset 提供向量搜索功能，形式为SQL 函数，以支持依赖于文本相似性的 AI 应用程序。

设置

安装 rockset 客户端。

yarn add @rockset/client

用法

提示

参见此部分了解有关安装集成包的一般说明。

npm

npm install @langchain/openai @langchain/community

Yarn

yarn add @langchain/openai @langchain/community

pnpm

pnpm add @langchain/openai @langchain/community

以下示例展示了如何使用 OpenAI 和 Rockset 来回答有关文本文件的问题

import * as rockset from "@rockset/client";
import { ChatOpenAI, OpenAIEmbeddings } from "@langchain/openai";
import { RocksetStore } from "@langchain/community/vectorstores/rockset";
import { RecursiveCharacterTextSplitter } from "@langchain/textsplitters";
import { readFileSync } from "fs";
import { ChatPromptTemplate } from "@langchain/core/prompts";
import { createStuffDocumentsChain } from "langchain/chains/combine_documents";
import { createRetrievalChain } from "langchain/chains/retrieval";

const store = await RocksetStore.withNewCollection(new OpenAIEmbeddings(), {
  client: rockset.default.default(
    process.env.ROCKSET_API_KEY ?? "",
    `https://api.${process.env.ROCKSET_API_REGION ?? "usw2a1"}.rockset.com`
  ),
  collectionName: "langchain_demo",
});

const model = new ChatOpenAI({ model: "gpt-3.5-turbo-1106" });
const questionAnsweringPrompt = ChatPromptTemplate.fromMessages([
  [
    "system",
    "Answer the user's questions based on the below context:\n\n{context}",
  ],
  ["human", "{input}"],
]);

const combineDocsChain = await createStuffDocumentsChain({
  llm: model,
  prompt: questionAnsweringPrompt,
});

const chain = await createRetrievalChain({
  retriever: store.asRetriever(),
  combineDocsChain,
});

const text = readFileSync("state_of_the_union.txt", "utf8");
const docs = await new RecursiveCharacterTextSplitter().createDocuments([text]);

await store.addDocuments(docs);
const response = await chain.invoke({
  input: "When was America founded?",
});
console.log(response.answer);
await store.destroy();

API 参考

• ChatOpenAI 来自 @langchain/openai
• OpenAIEmbeddings 来自 @langchain/openai
• RocksetStore 来自 @langchain/community/vectorstores/rockset
• RecursiveCharacterTextSplitter 来自 @langchain/textsplitters
• ChatPromptTemplate 来自 @langchain/core/prompts
• createStuffDocumentsChain 来自 langchain/chains/combine_documents
• createRetrievalChain 来自 langchain/chains/retrieval

相关

• 向量存储概念指南
• 向量存储操作指南