BasicsGenerating Structured Data

Generate Object

Earlier functions like generateText and streamText gave us the ability to generate unstructured text. However, if you want to generate structured data like JSON, you can provide a schema that describes the structure of your desired object to the generateObject function.

The function requires you to provide a schema using zod, a library for defining schemas for JavaScript objects. By using zod, you can also use it to validate the generated object and ensure that it conforms to the specified structure.

http://localhost:3000
View Notifications

Client

Let's create a simple React component that will call the getNotifications function when a button is clicked. The function will generate a list of notifications as described in the schema.

app/page.tsx
'use client';
import { useState } from 'react';
import { getNotifications } from './actions';
// Force the page to be dynamic and allow streaming responses up to 30 seconds
export const dynamic = 'force-dynamic';
export const maxDuration = 30;
export default function Home() {
const [generation, setGeneration] = useState<string>('');
return (
<div>
<button
onClick={async () => {
const { notifications } = await getNotifications(
'Messages during finals week.',
);
setGeneration(JSON.stringify(notifications, null, 2));
}}
>
View Notifications
</button>
<pre>{generation}</pre>
</div>
);
}

Server

Now let's implement the getNotifications function. We'll use the generateObject function to generate the list of notifications based on the schema we defined earlier.

app/actions.ts
'use server';
import { generateObject } from 'ai';
import { openai } from '@ai-sdk/openai';
import { z } from 'zod';
export async function getNotifications(input: string) {
'use server';
const { object: notifications } = await generateObject({
model: openai('gpt-4-turbo'),
system: 'You generate three notifications for a messages app.',
prompt: input,
schema: z.object({
notifications: z.array(
z.object({
name: z.string().describe('Name of a fictional person.'),
message: z.string().describe('Do not use emojis or links.'),
minutesAgo: z.number(),
}),
),
}),
});
return { notifications };
}