defining theme for multiple domains in wp-config.php

Well, I revisited this with a clearer head, and I’ve worked out why it wasn’t working.

Here’s the section of wp-settings.php responsible for loading the functions.php.

// Load functions for active theme.
if ( TEMPLATEPATH !== STYLESHEETPATH && file_exists(STYLESHEETPATH . '/functions.php') )
	include(STYLESHEETPATH . '/functions.php');
if ( file_exists(TEMPLATEPATH . '/functions.php') )
	include(TEMPLATEPATH . '/functions.php');

as you can see there, because the second conditional isn’t an ‘elseif’ it tries to load the functions PHP *twice*, if TEMPLATEPATH doesn’t match STYLESHEETPATH.

Of course this results in error central as existing functions are defined again.

So, either one hacks that, or better yet, one defines both in wp-config.php:

I’ve modified my function above, to make it simpler to add as many domains (and their themes) as you like.

Put this into wp-config.php, under the $table_prefix definition, and edit to match your details:

function domain_theme($domain) {
   define('WP_SITEURL', 'http://'.$domain);
   define('WP_HOME', 'http://'.$domain);
   define('TEMPLATEPATH', '/path/to/public_html/wp-content/themes/'.$domain);
   define('STYLESHEETPATH', '/path/to/public_html/wp-content/themes/'.$domain);
}
$domain = $_SERVER['SERVER_NAME'];
$domain = str_replace('www.', '', $domain);
if ($domain == 'altsite.mobi') domain_theme($domain);

Now, your main site’s theme folder can be called whatever you want, but your alternate site themes should be named after the domain they’re intended for, and bob’s your uncle. Just copy the if-statement at the end, to add additional domains safely.

If you want to be a rogue about it, you can just assume that you’ve done everything correctly, and forget the error checking by changing the last line to:

if ($domain !== 'mainsite.com') domain_theme($domain);

this will just assume that you’ve uploaded a theme for every domain you have parked at your site, and if you happen to access your site via a domain which doesn’t have a theme, you’ll probably get lots of error messages, so the first one is safer, but the second one is shorter if you have 15 domains parked at your site.

I thoroughly suggest you don’t use this to stuff google full of duplicate content, but there are PLENTY of legitimate reasons you might want it, so here it is.

I’m no rewriting guru… but here’s what I’m using myself to make this happen.

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{HTTP_HOST} !^(www\.)?yoursite\.com$ [NC]
RewriteRule ^robots.txt$ /robots_blocked.txt [NC,L]
</IfModule>

I put this above the wordpress section of the .htaccess, otherwise I suppose it would be clobbered.

What it does is quite simple. Any request for robots.txt from your main site (yoursite.com, with a www or without) are passed to a regular old robots.txt file which may or may not be there.

If any other domain (or subdomain) is used, the rule should trigger, thereby returning the contents of a file called robots_blocked.txt, under the guise of robots.txt

you can test this pretty easily by making two text files (robots.txt and robots_blocked.txt) in your web root, and toying with it in your browser.