<?php
namespace Yoast\WP\SEO\Integrations\Front_End;
use Yoast\WP\SEO\Conditionals\Front_End_Conditional;
use Yoast\WP\SEO\Helpers\Options_Helper;
use Yoast\WP\SEO\Integrations\Integration_Interface;
use Yoast\WP\SEO\Surfaces\Meta_Surface;
/**
* Class Feed_Improvements
*/
class Feed_Improvements implements Integration_Interface {
/**
* Holds the options helper.
*
* @var Options_Helper
*/
private $options;
/**
* Holds the meta helper surface.
*
* @var Meta_Surface
*/
private $meta;
/**
* Canonical_Header constructor.
*
* @codeCoverageIgnore It only sets depedencies.
*
* @param Options_Helper $options The options helper.
* @param Meta_Surface $meta The meta surface.
*/
public function __construct( Options_Helper $options, Meta_Surface $meta ) {
$this->options = $options;
$this->meta = $meta;
}
/**
* Returns the conditionals based in which this loadable should be active.
*
* @return array
*/
public static function get_conditionals() {
return [ Front_End_Conditional::class ];
}
/**
* Registers hooks to WordPress.
*
* @return void
*/
public function register_hooks() {
\add_filter( 'get_bloginfo_rss', [ $this, 'filter_bloginfo_rss' ], 10, 2 );
\add_filter( 'document_title_separator', [ $this, 'filter_document_title_separator' ] );
\add_action( 'do_feed_rss', [ $this, 'handle_rss_feed' ], 9 );
\add_action( 'do_feed_rss2', [ $this, 'send_canonical_header' ], 9 );
\add_action( 'do_feed_rss2', [ $this, 'add_robots_headers' ], 9 );
}
/**
* Filter `bloginfo_rss` output to give the URL for what's being shown instead of just always the homepage.
*
* @param string $show The output so far.
* @param string $what What is being shown.
*
* @return string
*/
public function filter_bloginfo_rss( $show, $what ) {
if ( $what === 'url' ) {
return $this->get_url_for_queried_object( $show );
}
return $show;
}
/**
* Makes sure send canonical header always runs, because this RSS hook does not support the for_comments parameter
*
* @return void
*/
public function handle_rss_feed() {
$this->send_canonical_header( false );
}
/**
* Adds a canonical link header to the main canonical URL for the requested feed object. If it is not a comment
* feed.
*
* @param bool $for_comments If the RRS feed is meant for a comment feed.
*
* @return void
*/
public function send_canonical_header( $for_comments ) {
if ( $for_comments || \headers_sent() ) {
return;
}
$queried_object = \get_queried_object();
// Don't call get_class with null. This gives a warning.
$class = ( $queried_object !== null ) ? \get_class( $queried_object ) : null;
$url = $this->get_url_for_queried_object( $this->meta->for_home_page()->canonical );
if ( ( ! empty( $url ) && $url !== $this->meta->for_home_page()->canonical ) || $class === null ) {
\header( \sprintf( 'Link: <%s>; rel="canonical"', $url ), false );
}
}
/**
* Adds noindex, follow tag for comment feeds.
*
* @param bool $for_comments If the RSS feed is meant for a comment feed.
*
* @return void
*/
public function add_robots_headers( $for_comments ) {
if ( $for_comments && ! \headers_sent() ) {
\header( 'X-Robots-Tag: noindex, follow', true );
}
}
/**
* Makes sure the title separator set in Yoast SEO is used for all feeds.
*
* @param string $separator The separator from WordPress.
*
* @return string The separator from Yoast SEO's settings.
*/
public function filter_document_title_separator( $separator ) {
return \html_entity_decode( $this->options->get_title_separator() );
}
/**
* Determines the main URL for the queried object.
*
* @param string $url The URL determined so far.
*
* @return string The canonical URL for the queried object.
*/
protected function get_url_for_queried_object( $url = '' ) {
$queried_object = \get_queried_object();
// Don't call get_class with null. This gives a warning.
$class = ( $queried_object !== null ) ? \get_class( $queried_object ) : null;
$meta = false;
switch ( $class ) {
// Post type archive feeds.
case 'WP_Post_Type':
$meta = $this->meta->for_post_type_archive( $queried_object->name );
break;
// Post comment feeds.
case 'WP_Post':
$meta = $this->meta->for_post( $queried_object->ID );
break;
// Term feeds.
case 'WP_Term':
$meta = $this->meta->for_term( $queried_object->term_id );
break;
// Author feeds.
case 'WP_User':
$meta = $this->meta->for_author( $queried_object->ID );
break;
// This would be NULL on the home page and on date archive feeds.
case null:
$meta = $this->meta->for_home_page();
break;
default:
break;
}
if ( $meta ) {
return $meta->canonical;
}
return $url;
}
}