function feeds_oai_pmh_parse in Feeds OAI-PMH Fetcher and Parser 7

Same name and namespace in other branches

1. 6 feeds_oai_pmh.inc \feeds_oai_pmh_parse()

Parse a raw response from an OAI-PMH endpoint into an array of items.

1 call to feeds_oai_pmh_parse()

FeedsOAIParser::parse in ./FeedsOAIParser.inc

Implementation of FeedsParser::parse().

File

./feeds_oai_pmh.inc, line 216

Code

function feeds_oai_pmh_parse($raw_xml) {

  // Items array
  $items = array();

  // Parse raw string into xml
  $xml = simplexml_load_string($raw_xml);
  if (!$xml) {
    return FALSE;
  }

  // If error element is set, we have a problem. Blow up before the
  // foreach blows up for us. More info this way too.
  if (isset($xml->error)) {
    return FALSE;
  }

  // Calculate base URL for requesting single metadata records.
  $record_request_base_url = (string) $xml->request . '?metadataPrefix=' . (string) $xml->request['metadataPrefix'];
  foreach ($xml->ListRecords->record as $xml_item) {

    // TODO: Handle items marked "deleted" in repository, if so configured.
    // TODO: Handle updates to existing nodes.
    // Skip items marked "deleted"
    if ($xml_item->header["status"] == "deleted") {
      continue;
    }
    $xml_dc_metadata = $xml_item->metadata
      ->children('http://www.openarchives.org/OAI/2.0/oai_dc/')
      ->children('http://purl.org/dc/elements/1.1/');
    $item = array(
      'guid' => (string) $xml_item->header->identifier,
      'datestamp' => strtotime((string) $xml_item->header->datestamp),
      'title' => (string) $xml_dc_metadata->title,
    );

    // Add a direct URL to the metadata record
    $item['metadata_record_url'] = $record_request_base_url . '&verb=GetRecord&identifier=' . $item['guid'];

    // Parse the setSpec from each item's header
    // Some implementations might repeat the same setSpec, so de-dupe.
    $set_spec_values = array();
    foreach ($xml_item->header->setSpec as $value) {
      $value = (string) $value;
      $set_spec_values[$value] = $value;
    }
    $item['setspec_raw'] = array_values($set_spec_values);

    // Parse elements
    $elements = array(
      #'title',
      'creator',
      'subject',
      'description',
      'publisher',
      'contributor',
      'date',
      'type',
      'format',
      'identifier',
      'source',
      'language',
      'relation',
      'coverage',
      'rights',
    );
    foreach ($elements as $element) {
      if (isset($xml_dc_metadata->{$element})) {
        $item[$element] = array();
        foreach ($xml_dc_metadata->{$element} as $value) {
          $value = (string) $value;

          // TODO: add callback functions to further process values (like convert dates to timestamps, split subjects, etc.)
          $item[$element][$value] = $value;
        }
        $item[$element] = array_values($item[$element]);
      }
    }

    // Add "url" element from "identifier" items that are URLs.
    foreach ($item['identifier'] as $value) {
      if (valid_url($value, TRUE)) {
        $item['url'][] = $value;
      }
    }
    $items[] = $item;
  }

  // if a resumption token is set, and it is non-null. Requests with
  // resumptionTokens come back with an empty self closing tag
  // indicating the end of the request.
  //  if (
  //    isset($xml->ListRecords->resumptionToken)
  //    && (string)$xml->ListRecords->resumptionToken != ''
  //    ) {
  //
  //    $resumption_token = (string)$xml->ListRecords->resumptionToken;
  //    dsm("Resumption token: " . $resumption_token);
  //    // Run the loop a second time, update the request url
  //    #$request = '?verb=ListRecords&resumptionToken='.
  //    #_oai_pmh_clean_url((string)$xml->ListRecords->resumptionToken);
  //    // Unneeded in theory, but makes me feel better
  //    #unset($xml->ListRecords->resumptionToken);
  //    #dsm("Next request will be: $request");
  //    #$times++;
  //    #if ($times == 2 ) {
  //    #  dsm("Looped $times times, breaking.");
  //    #  break;
  //    #}
  //  }

  #dsm("All the items returned:");

  #dpm($items);
  return array(
    'items' => $items,
  );
}