Hiding Custom Post Type from Google?

Question

I have a plugin that uses custom post type for holding content that I pull via a shortcode elsewhere. However on a new site I noticed one of the posts in the CPT started showing up in the google search results. The post isn't linked anywhere directly. How would that show up there? How can I hide it from showing up in google?

I set public to false, now that just turns the page into the home page. I don't know that this will completely fix my problem. What else can I do?

register_post_type('mycpt', array(
    'labels' => $labels,
    'public' => false,
    'show_ui' => true,
    'menu_icon' => $icon_svg,
    '_builtin' => false,
    'capability_type' => 'page',
    'hierarchical' => true,
    'rewrite' => false,
    'query_var' => 'mycpt',
    'exclude_from_search' => true,
    'supports' => array(
        'title', 'editor', 'revisions',
    ),
    'show_in_menu' => true,
));

Answer 1

If you are using an SEO plugin such as Yoast, it automatically adds all Custom Post Types (and Taxonomies) to the sitemap that is used by Google & other search engines.

You will need to explicitly exclude them from the sitemap e.g in Yoast, this is under the "Post Types"/"Taxomonies" tab in the "XML Sitemaps" settings page.

Also don't forget to remove the links from Google through Webmaster Tools - otherwise you have to wait for Google to re-index your site.

Answer 2

There is a way to hide a post type by default from Yoast. However your milage may vary depending on what you are doing with your post type. If you are using it on the front end directly then this won't work for you. In my case I was pulling the content via shortcodes.

So the 'public' argument when registering your post type enables/disables a few arguments at once. See the description here: https://codex.wordpress.org/Function_Reference/register_post_type

You can set these manually for a finer level of control. The argument I found that helped with my issue was publicly_queryable. By setting this to false, it disabled my custom post type from having front end pages. Which I didn't need. This hid the post type from Yoast. All the admin stuff continued to work, the post type was still functional in the ways I had needed it to be.