getWaiter('foo', ['bar' => 'baz']); * $waiter->promise()->then(function () { echo 'Done!'; }); * * @param string|callable $name Name of the waiter that defines the wait * configuration and conditions. * @param array $args Args to be used with each command executed * by the waiter. Waiter configuration options * can be provided in an associative array in * the @waiter key. * @return \Aws\Waiter * @throws \UnexpectedValueException if the waiter is invalid. */ public function getWaiter($name, array $args = []); }