protected function setManifestItems()
    {
        $m = $this->manifest;

        if (!empty($m)) {
            if (isset($m['service']) && is_array($m['service'])) {
                foreach ($m['service'] as $item => $value) {
                    if ($this->isFileService($item, $value)) {
                        $this->storageItems[$item] = $value;
                    } else {
                        $this->nonStorageItems[$item] = $value;
                    }
                }
            }

            if (count($this->getServices()) == 0) {
                throw new InternalServerErrorException('No items found in package manifest.');
            }
        }
    }