public function getNoncer()
    {
        if (!isset($this->noncer)) {
            $this->noncer = new self::$defaultNoncerClass($this->noncerLength);
            if (!$this->noncer instanceof NoncerInterface) {
                throw new \UnexpectedValueException('Noncer must implement Acquia\Rest\NoncerInterface');
            }
        }
        return $this->noncer;
    }