/** * @param Publication $publication * * @return DOMElement */ private function createRecordHeader(Publication $publication) { $xml = new DOMDocument('1.0', 'UTF-8'); $header = $xml->createElement('header'); $header->appendChild($xml->createElement('identifier', 'oai:' . $this->repositoryIdentifier . ':' . $publication->getId())); $header->appendChild($xml->createElement('datestamp', $publication->getDateAdded('Y-m-d'))); $keywords = $publication->getKeywords(); foreach ($keywords as $keyword) { $setSpec = str_replace(' ', '_', $keyword->getName()); $setSpec = strtolower($setSpec); $header->appendChild($xml->createElement('setSpec', $setSpec)); } return $header; }