=1` to internal links * for logged-in users so subsequent navigation bypasses the edge cache. * - `wp_redirect_filter` does the same on server-side redirects. * - `redirect_301_real_url` 301-redirects search-engine crawlers that landed on a buster * URL back to the canonical (busted-arg-stripped) URL. */ class Cache_Buster implements Module_Interface { public function init() { // SEO redirect for URLs indexed with the cache buster query arg. if ( Settings_Store::get_instance()->get( Constants::SETTING_SEO_REDIRECT, 1 ) > 0 ) { add_action( 'init', [ $this, 'redirect_301_real_url' ], 0 ); } add_action( 'wp_footer', [ $this, 'inject_cache_buster_js_code' ], PHP_INT_MAX ); add_action( 'admin_footer', [ $this, 'inject_cache_buster_js_code' ], PHP_INT_MAX ); // Append the cache buster to server-side redirects for logged-in users. add_filter( 'wp_redirect', [ $this, 'wp_redirect_filter' ], PHP_INT_MAX, 2 ); } /** * 301 anonymous visitors that hit a URL containing the cache buster back to the * canonical (stripped) URL. Search engines that indexed a busted URL get cleaned up. * * @return void */ public function redirect_301_real_url() { if ( ! is_user_logged_in() && ( isset( $_GET['swcfpc-preloader'] ) || isset( $_GET['swcfpc-purge-all'] ) ) ) { return; } if ( is_user_logged_in() || empty( $_SERVER['QUERY_STRING'] ) ) { return; } if ( strpos( $_SERVER['QUERY_STRING'], SWCFPC_CACHE_BUSTER ) === false ) { return; } $parts = parse_url( home_url() ); $current_uri = "{$parts['scheme']}://{$parts['host']}" . add_query_arg( null, null ); $parsed = parse_url( $current_uri ); $query_string = $parsed['query']; parse_str( $query_string, $params ); unset( $params[ SWCFPC_CACHE_BUSTER ] ); $query_string = http_build_query( $params ); $current_uri = "{$parts['scheme']}://{$parts['host']}"; if ( isset( $parsed['path'] ) ) { $current_uri .= $parsed['path']; } if ( strlen( $query_string ) > 0 ) { $current_uri .= "?{$query_string}"; } wp_redirect( $current_uri, 301 ); die(); } /** * Append the cache buster to outgoing redirects for logged-in users so the CDN * doesn't serve them a cached anonymous response after the redirect. * * @param string $location * @param int $status * @return string */ public function wp_redirect_filter( $location, $status ) { $settings = Settings_Store::get_instance(); if ( Bypass_Resolver::should_remove_cache_buster() ) { return $location; } if ( apply_filters( 'swcfpc_bypass_redirect_cache_buster', false, $location ) === true ) { return $location; } if ( ! $settings->is_cache_enabled() ) { return $location; } if ( ! is_user_logged_in() ) { return $location; } $cache_buster = SWCFPC_CACHE_BUSTER; if ( strpos( $location, $cache_buster ) === false ) { $location = add_query_arg( [ $cache_buster => '1' ], $location ); } return $location; } /** * Inject the JS that rewrites internal links to include the cache buster query arg * for logged-in users. Frontend uses `a` selector; admin uses a curated selector list * targeting the toolbar / preview / publish-success links so we don't touch every link * in the admin UI. * * @return void */ public function inject_cache_buster_js_code() { if ( ! Settings_Store::get_instance()->is_cache_enabled() ) { return; } if ( Bypass_Resolver::should_remove_cache_buster() ) { return; } if ( ! is_user_logged_in() ) { return; } if ( ! is_admin() && ( ( function_exists( 'amp_is_request' ) && \amp_is_request() ) || ( function_exists( 'ampforwp_is_amp_endpoint' ) && \ampforwp_is_amp_endpoint() ) ) ) { return; } $cache_buster = SWCFPC_CACHE_BUSTER; $selectors = 'a'; if ( is_admin() ) { $selectors = '#wp-admin-bar-my-sites-list a, #wp-admin-bar-site-name a, #wp-admin-bar-view-site a, #wp-admin-bar-view a, .row-actions a, .preview, #sample-permalink a, #message a, #editor .is-link, #editor .editor-post-preview, #editor .editor-post-permalink__link, .edit-post-post-link__preview-link-container .edit-post-post-link__link'; } ?>