Wordpress returns 404 on custom rewrite rule conflict in parameters

Question

I have been following the steps on the answer here and it worked wonders.

But my problem is on this part,

on the original:

add_filter('rewrite_rules_array', 'mmp_rewrite_rules');
function mmp_rewrite_rules($rules) {
    $newRules  = array();
    $newRules['custom-post-type-base/(.+)/(.+)/(.+)/(.+)/?$'] = 'index.php?custom_post_type_name=$matches[4]'; // my custom structure will always have the post name as the 5th uri segment
    $newRules['custom-post-type-base/(.+)/?$']                = 'index.php?taxonomy_name=$matches[1]'; 

    return array_merge($newRules, $rules);
} 

my version:

add_filter('rewrite_rules_array', 'mmp_rewrite_rules');
function mmp_rewrite_rules($rules) {
    $newRules  = array();
    $newRules['custom-post-type-base/(.+)/(.+)/(.+)/?$'] = 'index.php?custom_post_type=$matches[3]'; 
    $newRules['custom-post-type-base/(.+)/?$']           = 'index.php?custom_taxonomy=$matches[1]';

    return array_merge($newRules, $rules);
} 

Since my taxonomy has two levels, it couldn't recognize whether the 2nd param (custom-post-type-base/(.+)/[here]/) is a custom post or a custom taxonomy.. it returns correctly on custom taxonomy but returns 404 on a custom post type with the post type being categorized on the parent taxonomy.

See Sample URLS:

"/custom-post-type-base/taxonomy-parent/taxonomy-child/single-custom-post-type/"
/*works as single custom post*/

"/custom-post-type-base/taxonomy-parent/taxonomy-child/"
/*works as custom taxonomy page*/

"/custom-post-type-base/taxonomy-parent/"
/*works as custom taxonomy page too*/

"/custom-post-type-base/taxonomy-parent/single-custom-post-type/"
/*returns a 404*/

Answer 1

You have:

• A rewrite rule that handles the post being in the 5th part
• A rewrite rule to handle the taxonomy part

A rewrite rule to handle the post being in the 2nd or 3rd part isn't in the above list, hence why you get a 404.

If we take this rewrite rule:

$newRules['basename/(.+)/(.+)/(.+)/(.+)/?$'] = 'index.php?custom_post_type_name=$matches[4]'; // my custom structure will always have the post name as the 5th uri segment

And modify it slightly using some common sense, namely:

• basename/(.+)/(.+)/(.+)/(.+)/?$ ....

  custom_post_type_name=$matches[4]

  // my custom structure will always have the post name as the 5 th uri segment

• basename/(.+)/(.+)/(.+)/?$ ....

  custom_post_type_name=$matches[3]

  // my custom structure will always have the post name as the 4 th uri segment

• basename/(.+)/(.+)/?$ ....

  custom_post_type_name=$matches[2]

  // my custom structure will always have the post name as the 3 th uri segment

etc

Place these in ascending order prior to your existing rule, and repeat as many times as is necessary