Append custom parameter to taxonomy/term URI

Question

I have a Custom Post Type named "Cars" and 2 Custom Taxonomies "Ferrari" and "Lamborghini". Each taxonomy has 2 Terms: "New" and "Used".

These URIs work as expected:

http://myhost/ferrari/new
http://myhost/ferrari/used

The problem is, of course, when I append the car ID at the end I get a 404:

http://myhost/ferrari/new/123

I've been playing a lot with add_rewrite_rule/add_rewrite_tag and read many discussions here on StackExchange but I couldn't find a solution. I also tried WP Router and it actually works, but it almost entirely overrides the default routing so that it feels like a hack.

Question:

All I need is being able to route the URI with the appended ID to the same template as it would without, so from there I can make a custom query using the ID segment.

Thank you!

Answer 1

You can try this:

function my_car_rewrite_rules( $rules ) {
    $newrules = array();

    // add a rule for this kind of url:
    // http://myhost.com/cars/ferrari/used/123
    // => http://myhost.com/index.php?post_type=cars&ferrari=used&p=123 

    $newrules['^cars/([^/]+)/([^/]+)/([^/]+)$'] = 'index.php?post_type=cars&$matches[1]=$matches[2]&p=$matches[3]';
    return $newrules + $rules;
}
add_filter('rewrite_rules_array','my_car_rewrite_rules');

and remember to "save the permalinks" when testing.

I added /cars/ so this rewrite will not overwrite your other pages.

You can also try this more restrict rule:

$newrules['^cars/([a-z]+)/([a-z]+)/([0-9]+)$'] = 'index.php?post_type=cars&$matches[1]=$matches[2]&p=$matches[3]';

or even

$newrules['^cars/([ferrari|lamborghini]+)/([used|new]+)/([0-9]+)$'] = 'index.php?post_type=cars&$matches[1]=$matches[2]&p=$matches[3]';

To remove the CPT from URI (need to do it for each taxonomy)

$newrules['^ferrari/([^/]+)/([^/]+)$'] = 'index.php?post_type=cars&$ferrari=$matches[1]&p=$matches[2]';