Importing from "langchain/llms/openai" is deprecated.

[oliviermills]

Description

In your example you use the old method for LangChain :

https://github.com/vercel/ai/tree/main/examples/next-langchain/app/api/stream-data-chain/route.ts

You should no long user LLMChain and update to using invoke() and, here stream()

e.g.:

const chatPrompt = ChatPromptTemplate.fromMessages([...])
const chain = chatPrompt.pipe(chatModel)
response = await chain.pipe(outputParser).stream({...},{ callbacks: [handlers]})

Code example

const model = new OpenAI({ temperature: 0, streaming: true });
  const prompt = PromptTemplate.fromTemplate(
    'What is a good name for a company that makes {product}?',
  );
  const chain = new LLMChain({ llm: model, prompt });

Additional context

Should update the LangChainStream() to work with:

import { OpenAI } from '@langchain/openai'

[beeirl]

@oliviermills have u been able to get it working using chain.stream() and Vercel's LangChainStream()? If so, mind sharing a gist?

[oliviermills]

@oliviermills have u been able to get it working using chain.stream() and Vercel's LangChainStream()? If so, mind sharing a gist?

Not with the Vercel version of LangChainStream.. I implemented my own (https://dev.to/omills/vercel-ai-sdk-langchain-3edf) but this could be improved using AIStream I believe. You essentially need to pipe the right stream transformers. This uses the latest Vercel Ai sdk and latest Langchain.

[lgrammel]

I've updated the langchain integration: https://sdk.vercel.ai/providers/adapters/langchain