Ok, aqui está minha resposta completa: -
function prefix_register_post_type()
{
register_post_type(
'prefix_portfolio',
array(
'labels' => array(
'name' => __('Portfolio', 'text_domain'),
'singular_name' => __('Portfolio', 'text_domain'),
'menu_name' => __('Portfolio', 'text_domain'),
'name_admin_bar' => __('Portfolio Item', 'text_domain'),
'all_items' => __('All Items', 'text_domain'),
'add_new' => _x('Add New', 'prefix_portfolio', 'text_domain'),
'add_new_item' => __('Add New Item', 'text_domain'),
'edit_item' => __('Edit Item', 'text_domain'),
'new_item' => __('New Item', 'text_domain'),
'view_item' => __('View Item', 'text_domain'),
'search_items' => __('Search Items', 'text_domain'),
'not_found' => __('No items found.', 'text_domain'),
'not_found_in_trash' => __('No items found in Trash.', 'text_domain'),
'parent_item_colon' => __('Parent Items:', 'text_domain'),
),
'public' => true,
'menu_position' => 5,
'supports' => array(
'title',
'editor',
'thumbnail',
'excerpt',
'custom-fields',
),
'taxonomies' => array(
'prefix_portfolio_categories',
),
'has_archive' => true,
'rewrite' => array(
'slug' => 'portfolio',
),
)
);
}
add_action('init', 'prefix_register_post_type');
function prefix_register_taxonomy()
{
register_taxonomy(
'prefix_portfolio_categories',
array(
'prefix_portfolio',
),
array(
'labels' => array(
'name' => _x('Categories', 'prefix_portfolio', 'text_domain'),
'singular_name' => _x('Category', 'prefix_portfolio', 'text_domain'),
'menu_name' => __('Categories', 'text_domain'),
'all_items' => __('All Categories', 'text_domain'),
'edit_item' => __('Edit Category', 'text_domain'),
'view_item' => __('View Category', 'text_domain'),
'update_item' => __('Update Category', 'text_domain'),
'add_new_item' => __('Add New Category', 'text_domain'),
'new_item_name' => __('New Category Name', 'text_domain'),
'parent_item' => __('Parent Category', 'text_domain'),
'parent_item_colon' => __('Parent Category:', 'text_domain'),
'search_items' => __('Search Categories', 'text_domain'),
),
'show_admin_column' => true,
'hierarchical' => true,
'rewrite' => array(
'slug' => 'portfolio/category',
),
)
);
}
add_action('init', 'prefix_register_taxonomy', 0);
Você também deve registrar a taxonomia ao registrar uma postagem personalizada.
Depois disso, a solicitação seria:
wp-json/wp/v2/posts/?taxonomy=prefix_portfolio_categories'&term=your-any-category
Espero que isso possa ajudá-lo:)