Custom Error

Sometimes there is no error but you want to create an error for some reason. For example, an article page has been closed after it has been published for a while. Unfortunately, that page has been indexed by search engines. So there are some users entering that page directly.

The solution is to make this article page returns error 404 using throwError() helper.

import { throwError } from '@lib/api'

ArticleDetailPage.getInitialProps = async ({ query }) => {
  const data = await getArticleById(query.id)

  // Found the article, but it is not published yet or it is now closed.
  if (data.status === 'closed') {
    throwError(404)
  }

  return { data }
}

In other words, if you want to make a page error, just call throwError(xxx).