Unable to Delete info on Express article tutorial

Below at bottom, is POST request handler (function) which implements Delete feature for a book info and then re-directs to the link “./catalog/books” on the site .

But seems like it is not deleting the individual book object from database (mongoDB) and not re-directing back !

exports.author_delete_post = asyncHandler(async (req, res, next) => {

// Get details of author and all their books (in parallel)

console.log("POST request to author_delete_post route");

const [author, allBooksByAuthor] = await Promise.all([


  Book.find({ author: req.params.id }, "title summary").exec(),


//  console.log(author);

if (allBooksByAuthor.length > 0) {

  // Author has books. Render in same way as for GET route.

  res.render("author_delete", {


    title: "Delete Author",

    author: author,

    author_books: allBooksByAuthor,

    // action: mongoDB,




 else {

  // Author has no books. Delete object and redirect to the list of authors.

  await Author.findByIdAndDelete(req.body.author._id);