Allow nested folder paths in WordPress Multisite with subdirectories

sunrise.php

<?php
/** 
 * Allow nested folder paths in WordPress Multisite with subdirectories
 * Updated from http://maisonbisson.com/post/14052/wordpress-hacks-nested-paths-for-wpmu-blogs/ to account for latest WordPress code
 * .htaccess rules also need to be changed to:

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([[_0-9a-zA-Z-]+/]*)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([[_0-9a-zA-Z-]+/]*)?(wp-(content|admin|includes)/.*) $2 [L]
RewriteRule ^([[_0-9a-zA-Z-]+/]*)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]
 */
 
if ( defined( 'DOMAIN_CURRENT_SITE' ) && defined( 'PATH_CURRENT_SITE' ) ) {

  $current_site = new stdClass;
  $current_site->id = defined( 'SITE_ID_CURRENT_SITE' ) ? SITE_ID_CURRENT_SITE : 1;
  $current_site->domain = $domain = DOMAIN_CURRENT_SITE;
  $current_site->path = $path = PATH_CURRENT_SITE;
  if ( defined( 'BLOG_ID_CURRENT_SITE' ) ) {
  	$current_site->blog_id = BLOG_ID_CURRENT_SITE;
  } elseif ( defined( 'BLOGID_CURRENT_SITE' ) ) { // deprecated.
  	$current_site->blog_id = BLOGID_CURRENT_SITE;
  }
  
  
  $url = parse_url( $_SERVER['REQUEST_URI'], PHP_URL_PATH );
  
  $patharray = ( array ) explode( '/', trim( $url, '/' ) );
  $pathsearch = '';
  $blogsearch = '';
  
  if ( count( $patharray ) ) {
    foreach( $patharray as $pathpart ) {
      $pathsearch .= '/' . $pathpart;
      $blogsearch .= $wpdb->prepare( " OR (domain = %s AND path = %s) ", $domain, $pathsearch . '/' );
    }
  }
  
  $current_blog = $wpdb->get_row( $wpdb->prepare( "SELECT *, LENGTH( path ) as pathlen FROM $wpdb->blogs WHERE domain = %s AND path = '/'", $domain ) . $blogsearch . 'ORDER BY pathlen DESC LIMIT 1' );
  
  $blog_id = $current_blog->blog_id;
  $public = $current_blog->public;
  $site_id = $current_blog->site_id;
  
  $current_site = _ss_get_current_site_name( $current_site );

}

function _ss_get_current_site_name( $current_site ) {
  global $wpdb;
  $current_site->site_name = wp_cache_get( $current_site->id . ':current_site_name', "site-options" );
  if ( !$current_site->site_name ) {
    $current_site->site_name = $wpdb->get_var( $wpdb->prepare( "SELECT meta_value FROM $wpdb->sitemeta WHERE site_id = %d AND meta_key = 'site_name'", $current_site->id ) );
  
    if ( $current_site->site_name == null ) {
      $current_site->site_name = ucfirst( $current_site->domain );
    }
  
    wp_cache_set( $current_site->id . ':current_site_name', $current_site->site_name, 'site-options' );
  }
  return $current_site;
}

@adamsposto Did you manage to fix this? Same issue here! All works but wp-admin is always showing the root domain wp-admin.

Note: Just updated the code to get rid of a pesky wpdb:prepare() notice about using the incorrect number of arguments

Just noting that as @nanker27 pointed out, you do get an error when trying to create a site with a nested subdirectory. Missing or invalid site address.

Looking at the relevant code in the WP core, there's probably no good way of fixing this, as you'd need to somehow bypass old procedural PHP code. The simple workaround is just to create the page at a temporary url and then add the nested URL in by editing it after the fact. No need to manually edit in the DB.

@Falc's .htaccess fix is still working in 2018. The relevant bit being the following line:

RewriteRule ^(.+)?/(wp-(includes|admin|content)(/.*)?) $2 [L]

Hi everyone, I'm trying this solution but every time all css/js/images from wp-content just return 404. Have someone figured out how to solve this?

@phalkmin same problem here. did you solve?