Override WP_SITEURL and WP_HOME for WordPress Multisite
Update: full updated plugin code with additional description can be found here: http://justinsilver.com/technology/wordpress/wordpress-plugins/wordpress-plugin-wp-server-migration/
I was able to come up with a solution with the help of @user916011. I needed to be able to copy the
wp_options table(s) to my development environment as they contain configurations that are needed. To overcome the issue of not being able to set the WP_SITEURL and WP_HOME values in MultiSite, I wrote a custom filter to replace the _config_wp_siteurl() and _config_wp_home() functions that are available for non-multisite installs that is included in a plugin that is available network-wide and is configured in wp-config.php. I am then able to copy all of the database tables except wp_site and wp_blogs to a local database.I highly recommend the URL Token Replacement Techniques for WordPress 3.0 article by Chris Murphy to help handle URLs in your content.
This example assumes a subdomain multisite install, with a domain of example.com and two subdomains, www.example.com and second.example.com. The local development URLs will be www.example.local and second.example.local respectively.
Database Changes:
Update the domain value in wp_site:
UPDATE wp_site SET domain = 'example.local' WHERE domain = 'example.com';Update the domain value(s) in wp_blogs:
UPDATE wp_blogs SET domain = 'www.example.local' WHERE domain = 'www.example.com';UPDATE wp_blogs SET domain = 'second.example.local' WHERE domain = 'second.example.com';Plugin Code:The following plugin should be installed network-wide.
<?php/*Plugin Name: MultiSite WP_HOME and WP_SITEURLPlugin URI: http://doublesharp.com/Description: Allows wp_options values to be overwritten in wp-config.php for MultiSiteAuthor: Justin SilverVersion: 1.0Author URI: http://doublesharp.comLicense: GPL2*/function _ms_config_wp_siteurl( $url = '' ) { if (is_multisite()): global $blog_id, $current_site; $cur_blog_id = defined('BLOG_ID_CURRENT_SITE')? BLOG_ID_CURRENT_SITE : 1; $key = ($blog_id!=$cur_blog_id)? $blog_id.'_' : ''; $constant = 'WP_'.$key.'SITEURL'; if ( defined( $constant ) ) return untrailingslashit( constant($constant) ); endif; return $url;}add_filter( 'option_siteurl', '_ms_config_wp_siteurl' );function _ms_config_wp_home( $url = '' ) { if (is_multisite()): global $blog_id; $cur_blog_id = defined('BLOG_ID_CURRENT_SITE')? BLOG_ID_CURRENT_SITE : 1; $key = ($blog_id!=$cur_blog_id)? $blog_id.'_' : ''; $constant = 'WP_'.$key.'HOME'; if ( defined( $constant ) ) return untrailingslashit( constant($constant) ); endif; return $url;}add_filter( 'option_home', '_ms_config_wp_home' );?>Configure wp-config.php:
Add new constants to wp-config.php. The primary site should use the standard WP_HOME and WP_SITEURL and the tertiary URLs should use WP_{$blog_id}_HOME and WP_{$blog_id}_SITEURL
define('WP_HOME', 'http://www.example.local');define('WP_SITEURL', 'http://www.example.local');define('WP_2_HOME', 'http://secondary.example.local');define('WP_2_SITEURL', 'http://secondary.example.local');
You could use the update_option in functions.php
update_option("siteurl","http://example.com");update_option("home","http://example.com");
There's a similar question being asked here: Team Development of a Wordpress Site which I provided a possible solution for. In your case, you may not want to go to that extent (though it would be very flexible); however, you could always look at the portion of the answer that mentions a domain-replacement technique.
I've outlined that solution here: URL Token Replacement Techniques...