Help with rewrite rules for two post types

Question

I'm trying to setup two rewrite rules for two post types. Basically, the structure I want is this:

site.com/app/course/xxxx/ => adds query_var course

site.com/app/course/xxxx/theme/xxxx/ => adss query vars course and theme

I set up two add_rewrite_rule:

public function rewrite_rules(){
    add_rewrite_tag( '%course%', '([^&]+)' );
    add_rewrite_tag( '%theme%', '([^&]+)' );    

    add_rewrite_rule("^app/course/([^/]+)/?",'index.php?page_id=3400&course=matches[1]', 'top' );
    add_rewrite_rule('^app/course/([^/]+)/theme/([^/]+)/?','index.php?page_id=3400&course=$matches[1]&theme=$matches[2]', 'top' );
}

If I add just the first rule, it works. If I only add the second rule, it works too. But, if I add both, only the first rule works. The second rule loads a valid page, but the theme var is not set.

Am I doing something wrong? Any tips are welcome!

Answer 1

The first rule is capturing all requests. If you add a $ anchor at the end of the rules, they'll behave as expected (you could also just switch the order of the rules so the more specific one "wins").

add_rewrite_rule(
    '^app/course/([^/]+)/?$',
    'index.php?page_id=3400&course=matches[1]', 
    'top'
);
add_rewrite_rule(
    '^app/course/([^/]+)/theme/([^/]+)/?$',
    'index.php?page_id=3400&course=$matches[1]&theme=$matches[2]',
    'top'
);

Check out Monkeyman Rewrite Analyzer for debugging rules.

Also note that theme is used by WordPress internally as a POST or GET var, I suggest changing that to something unique to prevent any potential conflict.