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namespace Yoast\WP\SEO\Integrations\Front_End;
use WPSEO_Sitemaps_Router;
use Yoast\WP\SEO\Conditionals\Robots_Txt_Conditional;
use Yoast\WP\SEO\Helpers\Options_Helper;
use Yoast\WP\SEO\Helpers\Robots_Txt_Helper;
use Yoast\WP\SEO\Integrations\Integration_Interface;
use Yoast\WP\SEO\Presenters\Robots_Txt_Presenter;
* Handles adding the sitemap to the `robots.txt`.
class Robots_Txt_Integration implements Integration_Interface {
* Holds the options helper.
protected $options_helper;
* Holds the robots txt helper.
protected $robots_txt_helper;
* Holds the robots txt presenter.
* @var Robots_Txt_Presenter
protected $robots_txt_presenter;
* @param Options_Helper $options_helper Options helper.
* @param Robots_Txt_Helper $robots_txt_helper Robots txt helper.
* @param Robots_Txt_Presenter $robots_txt_presenter Robots txt presenter.
public function __construct( Options_Helper $options_helper, Robots_Txt_Helper $robots_txt_helper, Robots_Txt_Presenter $robots_txt_presenter ) {
$this->options_helper = $options_helper;
$this->robots_txt_helper = $robots_txt_helper;
$this->robots_txt_presenter = $robots_txt_presenter;
* Returns the conditionals based in which this loadable should be active.
public static function get_conditionals() {
return [ Robots_Txt_Conditional::class ];
* Initializes the integration.
* This is the place to register hooks and filters.
public function register_hooks() {
\add_filter( 'robots_txt', [ $this, 'filter_robots' ], 99999 );
if ( $this->options_helper->get( 'deny_search_crawling' ) && ! \is_multisite() ) {
\add_action( 'Yoast\WP\SEO\register_robots_rules', [ $this, 'add_disallow_search_to_robots' ], 10, 1 );
if ( $this->options_helper->get( 'deny_wp_json_crawling' ) && ! \is_multisite() ) {
\add_action( 'Yoast\WP\SEO\register_robots_rules', [ $this, 'add_disallow_wp_json_to_robots' ], 10, 1 );
if ( $this->options_helper->get( 'deny_adsbot_crawling' ) && ! \is_multisite() ) {
\add_action( 'Yoast\WP\SEO\register_robots_rules', [ $this, 'add_disallow_adsbot' ], 10, 1 );
* Filters the robots.txt output.
* @param string $robots_txt The robots.txt output from WordPress.
* @return string Filtered robots.txt output.
public function filter_robots( $robots_txt ) {
$robots_txt = $this->remove_default_robots( $robots_txt );
$this->maybe_add_xml_sitemap();
* Filter: 'wpseo_should_add_subdirectory_multisite_xml_sitemaps' - Disabling this filter removes subdirectory sites from xml sitemaps.
* @param bool $show Whether to display multisites in the xml sitemaps.
if ( \apply_filters( 'wpseo_should_add_subdirectory_multisite_xml_sitemaps', true ) ) {
$this->add_subdirectory_multisite_xml_sitemaps();
* Allow registering custom robots rules to be outputted within the Yoast content block in robots.txt.
* @param Robots_Txt_Helper $robots_txt_helper The Robots_Txt_Helper object.
\do_action( 'Yoast\WP\SEO\register_robots_rules', $this->robots_txt_helper );
return \trim( $robots_txt . \PHP_EOL . $this->robots_txt_presenter->present() . \PHP_EOL );
* Add a disallow rule for search to robots.txt.
* @param Robots_Txt_Helper $robots_txt_helper The robots txt helper.
public function add_disallow_search_to_robots( Robots_Txt_Helper $robots_txt_helper ) {
$robots_txt_helper->add_disallow( '*', '/?s=' );
$robots_txt_helper->add_disallow( '*', '/page/*/?s=' );
$robots_txt_helper->add_disallow( '*', '/search/' );
* Add a disallow rule for /wp-json/ to robots.txt.
* @param Robots_Txt_Helper $robots_txt_helper The robots txt helper.
public function add_disallow_wp_json_to_robots( Robots_Txt_Helper $robots_txt_helper ) {
$robots_txt_helper->add_disallow( '*', '/wp-json/' );
$robots_txt_helper->add_disallow( '*', '/?rest_route=' );
* Add a disallow rule for AdsBot agents to robots.txt.
* @param Robots_Txt_Helper $robots_txt_helper The robots txt helper.
public function add_disallow_adsbot( Robots_Txt_Helper $robots_txt_helper ) {
$robots_txt_helper->add_disallow( 'AdsBot', '/' );
* Replaces the default WordPress robots.txt output.
* @param string $robots_txt Input robots.txt.
protected function remove_default_robots( $robots_txt ) {
'`User-agent: \*[\r\n]+Disallow: /wp-admin/[\r\n]+Allow: /wp-admin/admin-ajax\.php[\r\n]+`',
* Adds XML sitemap reference to robots.txt.
protected function maybe_add_xml_sitemap() {
// If the XML sitemap is disabled, bail.
if ( ! $this->options_helper->get( 'enable_xml_sitemap', false ) ) {
$this->robots_txt_helper->add_sitemap( \esc_url( WPSEO_Sitemaps_Router::get_base_url( 'sitemap_index.xml' ) ) );
* Adds subdomain multisite' XML sitemap references to robots.txt.
protected function add_subdirectory_multisite_xml_sitemaps() {
// If not on a multisite subdirectory, bail.
if ( ! \is_multisite() || \is_subdomain_install() ) {
$sitemaps_enabled = $this->get_xml_sitemaps_enabled();
foreach ( $sitemaps_enabled as $blog_id => $is_sitemap_enabled ) {
if ( ! $is_sitemap_enabled ) {
$this->robots_txt_helper->add_sitemap( \esc_url( \get_home_url( $blog_id, 'sitemap_index.xml' ) ) );
* Retrieves whether the XML sitemaps are enabled, keyed by blog ID.
protected function get_xml_sitemaps_enabled() {
$is_allowed = $this->is_sitemap_allowed();
$blog_ids = $this->get_blog_ids();
foreach ( $blog_ids as $blog_id ) {
$is_enabled[ $blog_id ] = $is_allowed && $this->is_sitemap_enabled_for( $blog_id );
* Retrieves whether the sitemap is allowed on a sub site.
protected function is_sitemap_allowed() {
$options = \get_network_option( null, 'wpseo_ms' );
if ( ! $options || ! isset( $options['allow_enable_xml_sitemap'] ) ) {
return (bool) $options['allow_enable_xml_sitemap'];
* Retrieves whether the sitemap is enabled on a site.
* @param int $blog_id The blog ID.
protected function is_sitemap_enabled_for( $blog_id ) {
if ( ! $this->is_yoast_active_on( $blog_id ) ) {
$options = \get_blog_option( $blog_id, 'wpseo' );
if ( ! $options || ! isset( $options['enable_xml_sitemap'] ) ) {
return (bool) $options['enable_xml_sitemap'];
* Determines whether Yoast SEO is active.
* @param int $blog_id The blog ID.
protected function is_yoast_active_on( $blog_id ) {
return \in_array( 'wordpress-seo/wp-seo.php', (array) \get_blog_option( $blog_id, 'active_plugins', [] ), true ) || $this->is_yoast_active_for_network();
* Determines whether Yoast SEO is active for the entire network.
protected function is_yoast_active_for_network() {
$plugins = \get_network_option( null, 'active_sitewide_plugins' );
if ( isset( $plugins['wordpress-seo/wp-seo.php'] ) ) {
* Retrieves the blog IDs of public, "active" sites on the network.
protected function get_blog_ids() {
'network_id' => \get_current_network_id(),
return \get_sites( $criteria );