WordPress - Prefix Custom Post Type posts slugs

kli-wp-prefix-posts-slugs.php

<?php
/**
 * Prefix Posts Slugs
 * This hooks into wp_unique_post_slug and adds prefix to post slug. Eg: have post Hello title and slug will be my-prefix-hello.
 * @author Klipolis
 * @since 0.1.0
 * @version 0.1.0
 * @access public
 * @main WordPress
 */

/**
 * Prefix my post slugs
 */
add_filter( 'wp_unique_post_slug', 'prefix_wp_unique_post_slug', 2, 6 );
function prefix_wp_unique_post_slug( $slug, $post_ID, $post_status, $post_type, $post_parent, $original_slug ) {

	if ( $post_type, 'my_postype_only') ) {
		
		$prefix = 'my-prefix-';

		if ( strripos($slug, $prefix) !== 0 ) {
			$slug = $prefix . $slug;
		}
	}

	return $slug;
}