Create short URL with auto 301 redirect

Question

I found this post (Create additional short URL with custom field and 301 redirect) and tried to do this with a custom post type I created but it aint working and I dont know what I am doing wrong in this case. I got URL's like this:

example.com/vacatures/junior-adviseur-kabels-en-leidingen-p565148-6/

and I want to create a short URL like this:

example.com/redirect/p565148-6/

And make a 301 redirect to

example.com/vacatures/junior-adviseur-kabels-en-leidingen-p565148-6/

I got a custom post type called "Vacatures" and a custom field "vacature_id".

I allready got this but that doesn't do anything.

add_action( 'init', 'vacature_rewrite_rule' );
function vacature_rewrite_rule() {
    add_rewrite_tag( '%vacature_id%', '([a-zA-Z0-9]+)' );
    add_rewrite_rule(
        '^redirect([a-zA-Z0-9]+)?',
        'index.php?vacature_id=$matches[1]',
        'top'
    );
}

add_action( 'parse_request', 'wpd_catch_vacature_requests' );
function wpd_catch_vacature_requests( $query ) {
    if( ! is_admin() && isset( $query->query_vars['vacature_id'] ) ){
        $the_post = new WP_Query(
            array(
                'post_type' => 'vacatures',
                'meta_key'   => 'vacature_id',
                'meta_value' => $query->query_vars['vacature_id']
            )
        );
        if( $the_post->have_posts() ){
            wp_redirect( get_permalink( $the_post->post->ID ) );
        } else {
            wp_redirect( home_url() );
        }
    }
}

Answer 1

What you're trying to do, can be achived by simply using the parse_request hook; no need for the custom rewrite rule and tag.

1. So remove this (and you should flush the rewrite rules — just visit the permalink settings page):

   add_action( 'init', 'vacature_rewrite_rule' );
   function vacature_rewrite_rule() {
       ...
   }
   

2. Then use this modified function which performs the redirection:

   add_action( 'parse_request', 'wpd_catch_vacature_requests' );
   function wpd_catch_vacature_requests( $query ) {
       if( ! is_admin() && preg_match( '#^redirect/([\w\-]+)$#', $query->request, $matches ) ){
           $posts = get_posts(
               array(
                   'post_type'  => 'vacatures',
                   'meta_key'   => 'vacature_id',
                   'meta_value' => $matches[1],
                   'fields'     => 'ids'
               )
           );
   
           // Redirect to the post.
           if( ! empty( $posts ) ){ // a valid post found
               wp_redirect( get_permalink( $posts[0] ) );
           // Or otherwise, the homepage. Or you can remove this and a 404 page would be shown.
           } else {
               wp_redirect( home_url() );
           }
           exit;
       }
   }