Automatically Populate Post Taxonomy Data Based on Post Author Meta Data?

Question

I'm trying to use author meta data to automatically populate a custom taxonomy on a given author's post(s). Currently, the taxonomy is visible on the post page, but I intend on hiding it from the front end to avoid accidental user selections. (Also the reason for pre-population)

Note: The associated taxonomy terms and the author meta data are identical (the author meta data options are pulled dynamically from existing taxonomy terms).

For some reason - this is NOT working. I'm scratching my head trying to figure out why - I think the logic is correct. Am I missing something/can anyone help?

Thanks in advance.

function update_school($post_id) {

  $post_author_id = get_post_field( 'post_author', $post_id ); // get the post author ID
  $school_title = get_the_author_meta( 'school2', $post_author_id ); // from the post author ID, get the author meta
  $school_slug = get_the_author_meta( 'school', $post_author_id ); // from the post author ID, get the author meta

  $school_term = get_term_by('slug', $school_slug, 'school'); // get term by the author meta called "school"
  $school_term_name = $school_term->name; // from the slug, get the school term name


  // update the post taxonomy "school" with author meta school variables above  
  wp_set_post_terms( $post_id, $school_term_name, 'school' );

} 

// run function on post save
add_action('save_post', 'update_school');

Answer 1

Figured it out for anyone who wants to know:

function update_school( $post_id ) {
  $post_author_id = get_post_field( 'post_author', $post_id ); // get the post author ID
  $school_name = get_the_author_meta( 'school2', $post_author_id ); // from the post author ID, get the author meta
  $term = term_exists( $school_name, 'school');
  wp_set_post_terms( $post_id, $term, 'school' );

} 

// run function on post save
add_action( 'save_post', 'update_school' );