Custom Endpoint For Custom Post Type from Child Theme

Question

I'm working with a child theme. Main theme has a custom post type called "Place". I need to change that into "Location". However, I changed all levels using wp_post_types object.

Now I need to change endpoint. In frontend, URLs are look like domain.com/place/a-permalink. I need to change that into domain.com/location/a-permalink

But I cannot change slug.

I checked some questions like this one. But cannot understand how to use with custom post type. I badly need your advice.

EDIT: In Parent theme, post type was registered this way:

register_post_type( "$custom_post_type", 
                array(  'label'             => CUSTOM_MENU_TITLE,
                        'labels'            => array(   'name'                  =>  CUSTOM_MENU_NAME,
                                                        'singular_name'         =>  CUSTOM_MENU_SIGULAR_NAME,
                                                        'add_new'               =>  CUSTOM_MENU_ADD_NEW,
                                                        'add_new_item'          =>  CUSTOM_MENU_ADD_NEW_ITEM,
                                                        'edit'                  =>  CUSTOM_MENU_EDIT,
                                                        'edit_item'             =>  CUSTOM_MENU_EDIT_ITEM,
                                                        'new_item'              =>  CUSTOM_MENU_NEW,
                                                        'view_item'             =>  CUSTOM_MENU_VIEW,
                                                        'search_items'          =>  CUSTOM_MENU_SEARCH,
                                                        'not_found'             =>  CUSTOM_MENU_NOT_FOUND,
                                                        'not_found_in_trash'    =>  CUSTOM_MENU_NOT_FOUND_TRASH ),
                        'public'            => true,
                        'can_export'        => true,
                        'show_ui'           => true, // UI in admin panel
                        '_builtin'          => false, // It's a custom post type, not built in
                        '_edit_link'        => 'post.php?post=%d',
                        'capability_type'   => 'post',
                        'menu_icon'         => get_bloginfo('template_url').'/images/favicon.ico',
                        'hierarchical'      => false,
                        'rewrite'           => array("slug" => "$custom_post_type"), // Permalinks
                        'query_var'         => "$custom_post_type", // This goes to the WP_Query schema
                        'supports'          => array(   'title',
                                                        'author', 
                                                        'excerpt',
                                                        'thumbnail',
                                                        'comments',
                                                        'editor', 
                                                        'trackbacks',
                                                        'custom-fields',
                                                        'revisions') ,
                        'show_in_nav_menus' => true ,
                        'taxonomies'        => array("$custom_cat_type","$custom_tag_type")
                    )
                );

AND AGAIN, I CANNOT TOUCH PARENT THEME, I HAVE TO DO EVERYTHING FROM CHILD THEME.

Answer 1

When you register your custom post type, you should use rewrite like this:

add_action('init', 'create_location');
function create_location() {
  register_post_type('location',
    array(
      'labels' => array(
        'name' => __('Locations'),
        'singular_name' => __('Location')
      ),
      'public' => true,
      'rewrite' => array(
        'slug' => 'location'
      )
    )
  );
}  

Don't forget to update your permalinks by going to example.com/wp-admin/options-permalink.php and click on Save Changes.

You should also be able to modify an already registered post type by using register_post_type() once again from the child theme.

From the description for register_post_type():

Create or modify a post type. register_post_type should only be invoked through the 'init' action. It will not work if called before 'init', and aspects of the newly created or modified post type will work incorrectly if called later.

References

Post Types

Modifying post type - using the registered_post_type hook

Function Reference/register post type