nextjs-server-actions.mdx

title
Next.js Server Actions

You can find the project source code on GitHub. This guide provides detailed, step-by-step instructions on how to use Upstash RAG Chat with Next.js Server Actions. You can also explore our [Next.js Server Actions example](https://github.com/upstash/rag-chat/tree/master/examples/nextjs/server-actions) for detailed, end-to-end examples and best practices.

Project Setup

Create a new Next.js application and install @upstash/rag-chat package.

npx create-next-app@latest
cd my-app
npm install @upstash/rag-chat

Setup Upstash Redis

Create a Redis database using Upstash Console or Upstash CLI and copy the UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN into your .env file.

UPSTASH_REDIS_REST_URL=<YOUR_URL>
UPSTASH_REDIS_REST_TOKEN=<YOUR_TOKEN>

Setup Upstash Vector

Create a Vector index using Upstash Console or Upstash CLI and copy the UPSTASH_VECTOR_REST_URL and UPSTASH_VECTOR_REST_TOKEN into your .env file.

UPSTASH_VECTOR_REST_URL=<YOUR_URL>
UPSTASH_VECTOR_REST_TOKEN=<YOUR_TOKEN>

Setup QStash LLM

Navigate to QStash Console and copy the QSTASH_TOKEN into your .env file.

QSTASH_TOKEN=<YOUR_TOKEN>

Create a Next.js Server Action

Create /app/actions.ts:

"use server";

import { RAGChat, upstash } from "@upstash/rag-chat";
import { createServerActionStream } from "@upstash/rag-chat/nextjs";

const ragChat = new RAGChat({
  model: upstash("meta-llama/Meta-Llama-3-8B-Instruct"),
});

export const serverChat = async (message: string) => {
  const { output } = await ragChat.chat(message, { streaming: true });

  // 👇 adapter to let us stream from server actions
  return createServerActionStream(output);
};

Create a Chat Component

Create /app/components/chat.tsx using the server action:

"use client";

import { useState } from "react";
import { readServerActionStream } from "@upstash/rag-chat/nextjs";
import { serverChat } from "../actions";

export const Chat = () => {
  const [prompt, setPrompt] = useState('');
  const [response, setResponse] = useState('');

  const clientChat = async () => {
    const stream = await serverChat(prompt);

    for await (const chunk of readServerActionStream(stream)) {
      setResponse(prev => prev + chunk);
    }
  };

  return (
    <div className="flex flex-col items-start p-4">
      <input className="border" placeholder="Enter your prompt" value={prompt} onChange={e => setPrompt(e.target.value)} />  
      <button onClick={clientChat}>Start Chat</button>
      <div>{response}</div>
    </div>
  );
};

Update Home Page

Update /app/page.tsx using the Chat component:

import { Chat } from "./components/chat"

export default function Home() {
  return <Chat />;
}

Run & Deploy

Run the app locally with npm run dev, check http://localhost:3000/

Deploy your app with vercel