public function add_custom_values( $post_id, $raw ) {

		// No custom data, return early.
		if ( empty( $raw['custom'] ) ) {
			return;
		}

		foreach ( $raw['custom'] as $custom_key => $custom_vals ) {
			foreach ( $custom_vals as $val ) {
				$this->add_custom_value( $post_id, $custom_key, $val );
			}
		}
	}