Save Messages to Database
You can save the chat to an external database using the onFinish
callback handler present in the streamText
function.
@/app/api/chat/route.ts
import { openai } from '@ai-sdk/openai';import { saveChat } from '@/utils/queries';import { streamText, convertToCoreMessages } from 'ai';
export function POST(request) { const { id, messages } = await request.json();
const coreMessages = convertToCoreMessages(messages);
const result = streamText({ model: openai('gpt-4o'), system: 'you are a friendly assistant!', messages: coreMessages, onFinish: async ({ responseMessages }) => { try { await saveChat({ id, messages: [...coreMessages, ...responseMessages], }); } catch (error) { console.error('Failed to save chat'); } }, });
return result.toDataStream();}
The saveChat
function is a server action that saves the chat to the database. It first checks if the chat already exists in the database and updates the chat if it does. If the chat does not exist, it inserts a new chat into the database.
This example assumes that the database table schema has a messages
column that stores the chat messages as a JSON string of type Array<CoreMessage>
. You can modify the saveChat
function to suit your database schema.
@/app/utils/queries.ts
export async function saveChat({ id, messages, userId,}: { id: string; messages: any; userId: string;}) { try { const selectedChats = await db.select().from(chat).where(eq(chat.id, id));
if (selectedChats.length > 0) { return await db .update(chat) .set({ messages: JSON.stringify(messages), }) .where(eq(chat.id, id)); }
return await db.insert(chat).values({ id, createdAt: new Date(), messages: JSON.stringify(messages), userId, }); } catch (error) { console.error('Failed to save chat in database'); throw error; }}