How can I display an archive of only one category of my custom post type?

Question

This is different from the question: How to display categories of my Custom Post Type?

I have a custom post type - podcasts. I have added the taxonomy "category" as I want my 'podcasts' to share the 'category' taxonomy with my posts. I have an archive page (archive-podcasts.php) that displays the podcasts at the url /podcasts/, but it shows all the categories. I would like to display my podcasts in a single category at a time, such as at mysite.com/podcasts/category/mycategory/

or even better: mysite.com/category/mycategory/podcasts/

Ideally it would use my existing archive-podcasts.php template.

Here's my custom post type creation:

function podcast_post_type() {

// Set UI labels for Podcast post Type
    $labels = array(
       //redacted my labels because they aren't important here.
    );

// Set other options for Podcast post Type

    $args = array(
        'label'               => __( 'podcasts', 'understrap' ),
        'description'         => __( 'Podcasts', 'understrap' ),
        'labels'              => $labels,
        // Features this CPT supports in Post Editor
        'supports'            => array( 'title', 'editor', 'excerpt', 'author', 'thumbnail', 'comments', 'revisions', 'custom-fields', ),
        // You can associate this CPT with a taxonomy or custom taxonomy. 
        'taxonomies'          => array(  'category' ),
        /* A hierarchical CPT is like Pages and can have
        * Parent and child items. A non-hierarchical CPT
        * is like Posts.
        */  
        'hierarchical'        => false,
        'public'              => true,
        'show_ui'             => true,
        'show_in_menu'        => true,
        'show_in_nav_menus'   => true,
        'show_in_admin_bar'   => true,
        'menu_position'       => 5,
        'can_export'          => true,
        'has_archive'         => true,
        'exclude_from_search' => false,
        'publicly_queryable'  => true,
        'capability_type'     => 'post',
    );

    // Registering your Podcast post Type
    register_post_type( 'podcasts', $args );

}

The following code seemed promising but didn't work:

add_action('init', 'category_cpt_rewrites');

function category_cpt_rewrites() {
    $custom_post_types = array('podcasts'); //some example post types
    foreach ( $custom_post_types as $post_type ) {
        $rule = '^' . $post_type . '/category/(.+?)/?$';
        $rewrite = 'index.php?post_type=' . $post_type . '&category_name=$matches[1]';
        add_rewrite_rule($rule,$rewrite,'top');
    }
}

I actually kind of expected this would work automatically - that by adding the 'category' taxonomy to my post type,I thought Wordpress would have a url where I could access my podcast categories.

I've lost a lot of time to this, and it seems like it should be simple - any help is appreciated!

Answer 1

Try this and let us know if it works:

function custom_category_rewrite() {

    /**
     * Here you build an array containing the post type keys that you want
     * the rule to work for.
     */
    $custom_post_types = array('podcast');

    foreach ( $custom_post_types as $post_type ) {
        /**
         * Adds rewrite rule which will rewrite sth like http://yoursite.com/podcast/category/category-name/ to
         * http://yoursite.com/index.php?post_type=podcast&category_name=category-name
         */
        add_rewrite_rule( "^$post_type/category/(.+)/?$", 'index.php?post_type=' . $post_type . '&category_name=$matches[1]', 'top' );
    }

    flush_rewrite_rules();

}

add_action( 'init', 'custom_category_rewrite' );

Put the code within your functions.php.

Pay attention to the comments along the snippet.

Try accessing something like http://yoursite.com/podcast/category/category-name/ to perform a test.