import { Metadata, ResolvingMetadata } from 'next'  
 type Props = { 
 params: { id: string }   
 searchParams: {
     [key: string]: 
     string | string[] | undefined 
     } 
 };   
 
 export async function generateMetadata(
 { params, searchParams }: Props,
 parent: ResolvingMetadata)
 : Promise<Metadata> {
    
 // read route params   
 const id = params.id
      
 // fetch data   
 const product = await fetch('url)
 .then((res) => res.json())
      
 // optionally access and extend (rather than replace) parent metadata   
 const previousImages = (await parent)
 .openGraph?
 .images || []
      
 return {     
     title: product.title,
     openGraph: {
            images: [
            '/some-specific-page-image.jpg',
             ...previousImages
             ],     
            },
           }}
              
export default function Page({ params, searchParams }: Props) {}