External/non-WP rewrite rules

I have a fairly complex wordpress with multiple sub-directories:

example.com/sub1/
example.com/sub2/

I’m trying to implement some history/bookmark support, and to do that I need the URLS containing these directories to be rewritten to the directory, not the index page. From there AJAX can take over, interpret the first URL and load the content.

I believe to do this I need to use $wp_rewrite->non_wp_rules

So far I have not even been able to write a simple rewrite from one directory to another:

//flush the rules//
function test_flush_rewrites() 
{
 global $wp_rewrite;
 $wp_rewrite->flush_rules();
};
//add new rule//
function test_add_rewrites() 
{
 global $wp_rewrite;
 $test_new_non_wp_rules = array(
    'sub1/' => 'sub2',
 );
 $wp_rewrite->non_wp_rules = $test_new_non_wp_rules + $wp_rewrite->non_wp_rules;
};
//add the actions//
add_action('generate_rewrite_rules', 'test_add_rewrites');
add_action('admin_init', 'test_flush_rewrites');

This results in a 404 when I navigate to the “sub1” directory.

also

'sub1'    => 'sub2' // does nothing
'/sub1/'  => 'sub2' // does nothing
'/?sub1/' => 'sub2' // does nothing

I believe the rule i’d like to write in .htaccess should look something like this:

RewriteRule ^([^/]+)/.*$ /$1/ 

ideally i’d like to redirect sub1/anythinghere to sub1, sub2/anythinghere to sub2 and so on.

Thanks for any help.

Here are some notes.

• Install Toschos rewrite plugin
• Install Jan Fabrys rewrite analyzer plugin.
• Use the Rewrite API
• Add your rules to top.

There’s also the function add_external_rule(), which should be accessible via

$GLOBALS['wp_rewrite']->add_external_rule();

All your external rules are accessible via $wp_rewrite->non_wp_rules. Here’re the internals, that show you how the rules get added inside $wp_rewrite->mod_rewrite_rules():

// add in the rules that don't redirect to WP's index.php (and thus shouldn't be handled by WP at all)
foreach ( (array) $this->non_wp_rules as $match => $query) {
    // Apache 1.3 does not support the reluctant (non-greedy) modifier.
    $match = str_replace('.+?', '.+', $match);

    // If the match is unanchored and greedy, prepend rewrite conditions
    // to avoid infinite redirects and eclipsing of real files.
    //if ($match == '(.+)/?$' || $match == '([^/]+)/?$' ) {
        //nada.
    //}

    $rules .= 'RewriteRule ^' . $match . ' ' . $home_root . $query . " [QSA,L]\n";
}

The phpDocBlock for that method states the following

Retrieve mod_rewrite formatted rewrite rules to write to .htaccess.

Does not actually write to the .htaccess file, but creates the rules for the process that will.

Will add the non_wp_rules property rules to the .htaccess file before the WordPress rewrite rules one.