Block REST API except for Independent Analytics

block-rest-api.php

function block_rest_api_except_ia( $access ) {
    if (!is_user_logged_in() && $_SERVER['REQUEST_URI'] != '/wp-json/iawp/search') {
        return new WP_Error( 'rest_disabled', __('The WordPress REST API has been disabled.'), array( 'status' => rest_authorization_required_code()));
    }
    return $access;
}
add_filter( 'rest_authentication_errors', 'block_rest_api_except_ia );