How to filter collection rows while using .each() in laravel?

Question

I want to filter this $authors collection.

$authors = Author::get();

In my view, I need to show how many books an author is related.
I use .each() to merge the count to $authors and return it to where it was called.

return $authors->each(function($author, $key){

            $author->count = Author::findOrFail($author->id)->books()->count();

        });

Question is "How can I remove/filter if an author have not wrriten any of a book(count <= 0)?"

I tried this is and it failed.

return $authors->each(function($author, $key){

                $author->count = Author::findOrFail($author->id)->books()->count();
               $author->filter(function($author, $key){
                    return $author->count <= 0;
               })

            });

Answer 1

You should use withCount() to avoid N+1 and performance problems:

$authors = Author::withCount('books')->get();

In a Blade view, you'll be able to do:

$author->books_count

If you want to count the number of results from a relationship without actually loading them you may use the withCount method, which will place a {relation}_count column on your resulting models.

https://laravel.com/docs/5.4/eloquent-relationships#counting-related-models