WPCOM_VIP_Cache_Manager::queue_post_purge PHP Method

    public function queue_post_purge($post_id)
    {
        if ($this->site_cache_purged) {
            return false;
        }
        if (defined('WP_IMPORTING')) {
            $this->purge_site_cache();
            return false;
        }
        $post = get_post($post_id);
        if (empty($post) || 'revision' === $post->post_type || !in_array(get_post_status($post_id), array('publish', 'inherit', 'trash'), true)) {
            return false;
        }
        if (!is_post_type_viewable($post->post_type)) {
            return;
        }
        $post_purge_urls = array();
        $post_purge_urls[] = get_permalink($post_id);
        $post_purge_urls[] = home_url('/');
        // Don't just purge the attachment page, but also include the file itself
        if ('attachment' === $post->post_type) {
            $this->purge_urls[] = wp_get_attachment_url($post_id);
        }
        $taxonomies = get_object_taxonomies($post, 'object');
        foreach ($taxonomies as $taxonomy) {
            if (true !== $taxonomy->public) {
                continue;
            }
            $taxonomy_name = $taxonomy->name;
            $terms = get_the_terms($post_id, $taxonomy_name);
            if (false === $terms) {
                continue;
            }
            foreach ($terms as $term) {
                $post_purge_urls = array_merge($post_purge_urls, $this->get_purge_urls_for_term($term));
            }
        }
        // Purge the standard site feeds
        // @TODO Do we need to PURGE the comment feeds if the post_status is publish?
        $site_feeds = array(get_bloginfo('rdf_url'), get_bloginfo('rss_url'), get_bloginfo('rss2_url'), get_bloginfo('atom_url'), get_bloginfo('comments_atom_url'), get_bloginfo('comments_rss2_url'), get_post_comments_feed_link($post_id));
        $post_purge_urls = array_merge($post_purge_urls, $site_feeds);
        /**
         * Allows adding URLs to be PURGEd from cache when a given post ID is PURGEd
         *
         * Developers can hook this filter and check the post being purged in order
         * to also purge related URLs, e.g. feeds.
         *
         * Related category archives, tag archives, generic feeds, etc, are already
         * included to be purged (see code above).
         *
         * PLEASE NOTE: Your site benefits from the performance that our HTTP
         * Reverse Proxy Caching provides, and purging URLs from that cache
         * should be done cautiously. VIP may push back on use of this filter
         * during initial code review and pre-deployment review where we
         * see issues.
         *
         * @deprecated 1.1 Use `wpcom_vip_cache_purge_{post_type}_urls` instead
         * @param array $this->purge_urls {
         *     An array of URLs for you to add to
         * }
         * @param type  $post_id The ID of the post which is the primary reason for the purge
         */
        $post_purge_urls = apply_filters('wpcom_vip_cache_purge_urls', $post_purge_urls, $post_id);
        $this->purge_urls = array_merge($this->purge_urls, $post_purge_urls);
        /**
         * Allows adding URLs to be PURGEd from cache when a given post ID is PURGEd
         *
         * Developers can hook this filter and check the post being purged in order
         * to also purge related URLs, e.g. feeds.
         *
         * Related category archives, tag archives, generic feeds, etc, are already
         * included to be purged (see code above).
         *
         * PLEASE NOTE: Your site benefits from the performance that our HTTP
         * Reverse Proxy Caching provides, and purging URLs from that cache
         * should be done cautiously. VIP may push back on use of this filter
         * during initial code review and pre-deployment review where we
         * see issues.
         *
         * @param array $this->purge_urls {
         *     An array of URLs for you to add to
         * }
         * @param type  $post_id The ID of the post which is the primary reason for the purge
         */
        $this->purge_urls = apply_filters("wpcom_vip_cache_purge_{$post->post_type}_post_urls", $this->purge_urls, $post_id);
        $this->purge_urls = array_unique($this->purge_urls);
        return true;
    }