Jetpack_RelatedPosts::init_raw PHP Method

    public static function init_raw()
    {
        static $instance = NULL;
        if (!$instance) {
            if (class_exists('WPCOM_RelatedPosts') && method_exists('WPCOM_RelatedPosts', 'init_raw')) {
                $instance = WPCOM_RelatedPosts::init_raw();
            } else {
                $instance = new Jetpack_RelatedPosts_Raw(get_current_blog_id(), Jetpack_Options::get_option('id'));
            }
        }
        return $instance;
    }

/**
 * VIP Legacy Related Posts (get post_id, title, url)
 *
 * Don't use for new projects, just use WPCOM_RelatedPosts directly, since it has hooks
 * like jetpack_relatedposts_filter_args, jetpack_relatedposts_filter_filters
 * 
 * For backwards compatability, this function finds related posts on the current blog 
 * using Elasticsearch, then converts the results to match the original sphere results format.
 * 
 * @param int $max_num Optional. Maximum number of results you want (default: 5).
 * @param array $additional_stopwords No longer used.
 * @param bool $exclude_own_titles No longer used.
 * @return array of related posts.
 */
function wpcom_vip_get_flaptor_related_posts($max_num = 5, $additional_stopwords = array(), $exclude_own_titles = true)
{
    if (method_exists('Jetpack_RelatedPosts', 'init_raw')) {
        $post_id = get_the_ID();
        $related = Jetpack_RelatedPosts::init_raw()->set_query_name('MLT-VIP-Flaptor')->get_for_post_id($post_id, array('size' => $max_num));
        $host = parse_url(home_url(), PHP_URL_HOST);
        $source_info = array('sourcename' => get_bloginfo('name'), 'sourceurl' => home_url(), 'sourcetype' => 'same_domain');
        if ($related) {
            //rebuilding the array to match sphere related posts (and flaptor related posts)
            $results = array();
            foreach ($related as $result) {
                $results[] = array('post_id' => $result['id'], 'url' => get_permalink($result['id']), 'title' => get_the_title($result['id']), 'timestamp' => get_the_time('Y-m-d', $result['id']), 'host' => $host, 'source' => $source_info);
            }
            return $results;
        }
        return false;
    } else {
        // Fallback for local environments where flaptor isn't available
        $related_posts = array();
        $host = parse_url(home_url(), PHP_URL_HOST);
        $source_info = array('sourcename' => get_bloginfo('name'), 'sourceurl' => home_url(), 'sourcetype' => 'same_domain');
        $post_id = get_the_ID();
        $related_query_args = array('posts_per_page' => $max_num);
        $categories = get_the_category($post_id);
        if (!empty($categories)) {
            $related_query_args['cat'] = $categories[0]->term_id;
        }
        $related_query = new WP_Query($related_query_args);
        foreach ($related_query->get_posts() as $related_post) {
            $related_post_id = $related_post->ID;
            $related_posts[] = array('url' => get_permalink($related_post_id), 'title' => get_the_title($related_post_id), 'timestamp' => get_the_time('Y-m-d', $related_post_id), 'host' => $host, 'source' => $source_info, 'post_id' => $related_post_id);
        }
        return $related_posts;
    }
}