<?php
/*
Plugin Name: Local WP Live Link Helper
Plugin URI: https://localwp.com
Description: Makes WordPress URL functions relative to play nicely with Live Links.
Version: 2.0
Author: Flywheel
Author URI: http://getflywheel.com
License: GPLv2 or later
*/
class LocalWP_Live_Link_Helper {
/**
* host/domain parsed from 'home' option
*
* @var string|null
*/
public $home_domain;
public function __construct() {
$this->home_domain = str_replace( '/^www./', '', parse_url( get_option( 'home' ), PHP_URL_HOST ) );
$this->add_filters();
}
/**
* @return string Host from server along with port re-added if using localhost routing mode.
*/
public function get_local_host() {
$original = str_replace( '/^www./', '', $_SERVER['HTTP_HOST'] );
/**
* If using localhost and the port isn't in HTTP_HOST then it needs to be re-added.
*/
if ( $original === 'localhost' ) {
$original .= ':' . $_SERVER['SERVER_PORT'];
}
return $original;
}
/**
* Convenience method to get tunnel domain from headers.
*
* @return string
*/
public function get_tunnel_host() {
return $_SERVER['HTTP_X_ORIGINAL_HOST'];
}
/**
* @return void
*/
public function add_filters() {
/**
* Do not add any of these filters if the X-Original-Host header is missing.
*/
if ( empty( $_SERVER['HTTP_X_ORIGINAL_HOST'] ) ) {
return;
}
add_action( 'send_headers', array( $this, 'send_private_cache_control_header' ), 9999 );
add_action('send_headers', array($this, 'send_local_host_header'), 9999);
remove_action( 'template_redirect', 'redirect_canonical' );
$local_to_tunnel_filters = array(
'get_rest_url',
'wp_redirect',
'bloginfo_url',
'the_permalink',
'wp_list_pages',
'wp_list_categories',
'the_content_more_link',
'the_content',
'the_tags',
'the_author_posts_link',
'post_link',
'post_type_link',
'page_link',
'attachment_link',
'get_shortlink',
'post_type_archive_link',
'get_pagenum_link',
'get_comments_pagenum_link',
'term_link',
'search_link',
'day_link',
'month_link',
'year_link',
'option_siteurl',
'blog_option_siteurl',
'option_home',
'admin_url',
'get_admin_url',
'get_site_url',
'network_admin_url',
'home_url',
'includes_url',
'site_url',
'site_option_siteurl',
'network_home_url',
'network_site_url',
'get_the_author_url',
'get_comment_link',
'wp_get_attachment_image_src',
'wp_get_attachment_thumb_url',
'wp_get_attachment_url',
'wp_login_url',
'wp_logout_url',
'wp_lostpassword_url',
'get_stylesheet_uri',
'get_locale_stylesheet_uri',
'script_loader_src',
'style_loader_src',
'get_theme_root_uri',
'theme_root_uri',
'plugins_url',
'stylesheet_directory_uri',
'template_directory_uri'
);
foreach ( $local_to_tunnel_filters as $local_to_tunnel_filter ) {
add_filter( $local_to_tunnel_filter, array( $this, 'make_link_tunnel' ) );
}
add_filter( 'pre_update_option', array( $this, 'make_link_local' ) );
add_filter( 'wp_insert_post_data', array( $this, 'make_link_local_in_posts' ), 9999 );
}
/**
* Prevent possible cache poisoning by sending Cache-Control private header whenever the domain is replaced.
*
* @return void
*/
public function send_private_cache_control_header() {
header( 'Cache-Control: private' );
}
/**
* Send original domain so the tunnel server can perform a replacement with it.
*/
public function send_local_host_header()
{
header('X-Local-Host: ' . $this->get_local_host());
}
/**
* Convenience method for replacing old host with new host.
*
* @param string $old Host to be replaced
* @param string $new Host to use as replacement
* @param string $subject Replacement subject
*/
public function replace_host( $old, $new, $subject ) {
$subject = str_replace( 'www.' . $old, $new, $subject );
$subject = str_replace( $old, $new, $subject );
return $subject;
}
/**
* Generic replacement of the site's local hostname to the tunnel hostname
*
* @param string $str String provided by the filter
*
* @return string String with local hostname replaced with the tunnel hostname
*/
public function make_link_tunnel( $str ) {
$local_host = $this->get_local_host();
$tunnel_host = $this->get_tunnel_host();
$str = $this->replace_host( $local_host, $tunnel_host, $str );
$str = $this->replace_host( $this->home_domain, $tunnel_host, $str );
/**
* Force HTTPS, but not for local dev testing setup ($tunnel_host ends with tunnel.testing:<port> )
*/
if (!preg_match('/^.*tunnel\.testing:\d+$/i', $tunnel_host)) {
$str = str_replace( 'http://' . $tunnel_host, 'https://' . $tunnel_host, $str );
}
return $str;
}
/**
* Generic replacement of the site's tunnel hostname to the local hostname,
* used when saving options to the database via the pre_update_option filter hook
*
* @param mixed $option Option being saved, provided by the filter. Will
* usually be a serialized string, but may be an
* unserialized type in some cases. See:
* https://developer.wordpress.org/reference/functions/get_option/
*/
public function make_link_local( $option ) {
if (gettype($option) !== 'string') {
$old_str = serialize($option);
$new_str = $this->replace_host( $this->get_tunnel_host(), $this->home_domain, $old_str );
return unserialize($new_str);
}
return $this->replace_host( $this->get_tunnel_host(), $this->home_domain, $option );
}
/**
* Go through post properties and replace the tunnel host with the local host
*
* @param WP_Post $post
*/
public function make_link_local_in_posts( $post ) {
$post['post_content'] = $this->make_link_local( $post['post_content'] );
return $post;
}
}
new LocalWP_Live_Link_Helper();
