Rewrite rules for custom post type

Question

There is a nonhierarchical custom post type "news".

/news/
/news/page/2/
/news/post_slug/

Each post has custom field "views". When someone opens post, field's value increased by one.

Would like to sort posts by this custom field, by its value.

/news/
/news/views/ = /news/?sort=views (get posts with custom field "views" and sort asc)
/news/views/page/2/ = /news/?sort=views&page=2 (similar to previous, next page)
/news/post_slug/

Got working /news/?sort=views, but this link is not human-like.

It should be transformed to /news/views/ and be able to handle pagination.

How can we do this?

Answer 1

You need to look at add_rewrite_tag() and add_rewrite_rule()

Also read this and this topics. They are very close to you issue.

After you setup rewrite rule don't forget to flush rules

add_action( 'wp_loaded','my_flush_rules' ); // flush_rules() if our rules are not yet included
function my_flush_rules(){
    $rules = get_option( 'rewrite_rules' );
    $pattern = 'news/([^/]+)?'; // the same pattern that was used in add_rewrite_rule
    if ( !isset( $rules[$pattern] ) ) {
        global $wp_rewrite;
        $wp_rewrite->flush_rules();
    }
}