Auto disable comments with custom field

by

Editing your code to use a custom field is fairly trivial…

function close_comments( $posts ) {
  if ( !is_single() ) { 
    return $posts; 
  }
  $cmeta = get_post_meta($posts[0]->ID,'your_field_name',true);
  if ( $posts[0]->post_date_gmt < $cmeta ) {
    $posts[0]->comment_status="closed";
    $posts[0]->ping_status="closed";
  }
  return $posts;
}
add_filter( 'the_posts', 'close_comments' );

I am not sure that that approach is the right one though.

  1. You are really just brute forcing a closed status. This is a
    “display only” hack. It doesn’t change the database status at all.
  2. This runs on the front end, every time any post displays and runs for many other queries as well. That strikes me as pretty profligate.

I think I would rethink the whole thing to use wp_cron