Grpc\BaseStub::_checkConnectivityState PHP Method

    private function _checkConnectivityState($new_state)
    {
        if ($new_state == \Grpc\CHANNEL_READY) {
            return true;
        }
        if ($new_state == \Grpc\CHANNEL_FATAL_FAILURE) {
            throw new \Exception('Failed to connect to server');
        }
        return false;
    }