CODE EXAMPLE FOR TYPESCRIPT

getserversideprops

export async function getStaticPaths() {
  const res = await fetch(`${baseUrl}/wp-json/wp/v2/posts`)
  const posts = await res.json()
  //paths is array of objects which is contains one params property with id or slug
  const paths = posts.map(({ slug }) => ({ params: { slug: `${slug}` } }))

  return {
    paths,
    //fallback true mean there is no slug in build time then it will not shown 404 error 
    // and fetch data from server and show it
    fallback: true,
  }
}