How to stop permalink redirects for a particular slug

Question

I have a large number of posts that each represent a very specific type of data. Each post title is the SKU for the data & information. Folks have become pretty savvy on the URL structure and their shortcuts (redirects) are causing them to get incorrect data. Using the wrong data is NOT a good thing in this case.

For example, if my actual slug is example.com/esm/010HHHH

• example.com/010HHHH redirects to example.com/esm/010HHHH (Good)
• example.com/010 could redirect to any item that starts with 010 such as example.com/esm/010AAAA (Not Good)

The preferred behavior is to simply get a 404 error for any post that is not exact for any posts that have a slug of /esm.

I have successfully solved the issue by removing the canonical filter. However, I would like the "normal" canonical behavior for any other slugs.

remove_filter('template_redirect', 'redirect_canonical');

Answer 1

maybe this will help :

add_filter( 'redirect_canonical','custom_disable_redirect_canonical' ); 
function custom_disable_redirect_canonical( $redirect_url, $requested_url ) {
    if ( /* your condition */ ) {
        return $redirect_url;
    } else {
        return $requested_url;
    }
}

Answer 2

This seems to be working. If the URL that WP wants to redirect to has "esm" in the url, it will simply return a 404. If not, it can go on its merry little way.

add_filter( 'redirect_canonical','custom_disable_redirect_canonical' );
function custom_disable_redirect_canonical( $redirect_url, $requested_url ) {
  if ( preg_match("/esm/",$redirect_url) ) {
    return FALSE;
  } else {
    return $redirect_url;
  }
}