External/non-WP rewrite rules

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.