D-Net

	private static long last_cache_update = 0;

	private static final Map<String, Map<String, String>> cached_vocabularies = new HashMap<>();

	private static final Map<String, DatasourceEntry> cached_datasources = new HashMap<>();

	private static final Map<String, String> cached_contexts = new HashMap<>();

	public String asOafRecord(final VelocityEngine ve,

			final ISLookUpService lookupService,

			final String oafSchemaLocation,

							  final String community_api) throws Exception {

		if (StringUtils.isBlank(getOriginalId())

				&& StringUtils

						.isBlank(getOpenaireId())) { throw new DirecIndexApiException("One of the following fields is required: originalId or openaireId"); }

		if (StringUtils.isBlank(getTitle())) { throw new DirecIndexApiException("A required field is missing: title"); }

		if (StringUtils.isBlank(getUrl())) { throw new DirecIndexApiException("A required field is missing: url"); }

		if (StringUtils.isBlank(getLicenseCode()) && StringUtils.isBlank(getAccessRightCode())) { throw new DirecIndexApiException("A required field is missing: accessRightCode"); }

		if (StringUtils.isBlank(getResourceType())) { throw new DirecIndexApiException("A required field is missing: resourceType"); }

		if (StringUtils.isBlank(getCollectedFromId())) { throw new DirecIndexApiException("A required field is missing: collectedFromId"); }

		if (StringUtils.isBlank(getType())) { throw new DirecIndexApiException("A required field is missing: type"); }

		final DatasourceEntry collectedFromEntry = getDatasourceInfo(collectedFromId, lookupService);

		final DatasourceEntry hostedByEntry = getDatasourceInfo(hostedById, lookupService);

		if (StringUtils.isBlank(openaireId)) {

			setOpenaireId(calculateOpenaireId(originalId, collectedFromEntry));

		}

		if (!openaireId

				.matches("^\\w{12}::\\w{32}$")) { throw new DirecIndexApiException(

						"Invalid openaireId: " + openaireId + " - regex ^\\w{12}::\\w{32}$ not matched"); }

		final Map<String, Object> model = new HashMap<>();

		model.put("esc", new EscapeXml());

		model.put("util", new OpenAIRESubmitterUtils(community_api));

		model.put("pub", this);

		model.put("objIdentifier", getOpenaireId());

		model.put("oafSchemaLocation", oafSchemaLocation);

		model.put("resultTypes", getVocabulary("dnet:result_typologies", lookupService));

		model.put("rights", getVocabulary("dnet:access_modes", lookupService));

		model.put("resourceTypes", getVocabulary("dnet:publication_resource", lookupService));

		model.put("pidTypes", getVocabulary("dnet:pid_types", lookupService));

		model.put("languages", getVocabulary("dnet:languages", lookupService));

		model.put("contexts", getContexts(lookupService));

		model.put("dateOfCollection", new SimpleDateFormat("yyyy-MM-dd\'T\'hh:mm:ss\'Z\'").format(new Date()));

		model.put("collectedFrom", collectedFromEntry);

		model.put("hostedBy", hostedByEntry);

		return VelocityEngineUtils.mergeTemplateIntoString(ve, "/eu/dnetlib/openaire/directindex/indexRecord.xml.vm", "UTF-8", model);

	}

	private static String calculateOpenaireId(final String originalId, final DatasourceEntry collectedFromEntry) {

		return collectedFromEntry.getPrefix() + "::" + Hashing.md5(originalId);

	}

	public static String calculateOpenaireId(final String originalId, final String collectedFromId, final ISLookUpService lookupService)

			throws ISLookUpException {

		return calculateOpenaireId(originalId, getDatasourceInfo(collectedFromId, lookupService));

	}

	private synchronized static DatasourceEntry getDatasourceInfo(final String dsId, final ISLookUpService lookupService) throws ISLookUpException {

		if (StringUtils

				.isBlank(dsId)) { return new DatasourceEntry("openaire____::1256f046-bf1f-4afc-8b47-d0b147148b18", "Unknown Repository", "unknown_____"); }

		if (!cached_datasources.containsKey(dsId)) {

			final String query =

					"collection('/db/DRIVER/RepositoryServiceResources/RepositoryServiceResourceType')//CONFIGURATION[./DATASOURCE_ORIGINAL_ID='" + dsId

							+ "']/concat(./OFFICIAL_NAME, ' @@@ ', .//FIELD/value[../key='NamespacePrefix'])";

			final String s = lookupService.getResourceProfileByQuery(query);

			final String[] arr = s.split("@@@");

			final DatasourceEntry ds = new DatasourceEntry(dsId, arr[0].trim(), arr[1].trim());

			if (StringUtils.isBlank(ds.getName()) || StringUtils.isBlank(ds.getPrefix())) {

				log.error("Invalid datasource id: " + dsId);

				throw new ISLookUpException("Invalid datasource id: " + dsId);

			} else {

				cached_datasources.put(dsId, ds);

			}

		}

		return cached_datasources.get(dsId);

	}

	private synchronized static Map<String, String> getVocabulary(final String voc, final ISLookUpService lookupService) throws ISLookUpException {

		if (DateUtils.now() - last_cache_update < TimeUnit.MINUTES.toMillis(15) && cached_vocabularies.containsKey(voc)) {

			return cached_vocabularies.get(voc);

		} else {

			final String query = "collection('/db/DRIVER/VocabularyDSResources/VocabularyDSResourceType')[.//VOCABULARY_NAME/@code='" + voc

					+ "']//TERM/concat(@code, ' @@@ ', @english_name)";

			final Map<String, String> map = new HashMap<>();

			for (final String s : lookupService.quickSearchProfile(query)) {

				final String[] arr = s.split("@@@");

				map.put(arr[0].trim(), arr[1].trim());

			}

			cached_vocabularies.put(voc, map);

			last_cache_update = DateUtils.now();

			return map;

		}

	}

	private synchronized static Map<String, String> getContexts(final ISLookUpService lookupService) throws ISLookUpException {

		if (DateUtils.now() - last_cache_update > TimeUnit.MINUTES.toMillis(15) || cached_contexts.isEmpty()) {

			final String query =

					"collection('/db/DRIVER/ContextDSResources/ContextDSResourceType')[.//context/@type='community' or .//context/@type='ri']//*[name()='context' or name()='category' or name()='concept']/concat(@id, ' @@@ ', @label)";

			cached_contexts.clear();

			for (final String s : lookupService.quickSearchProfile(query)) {

				final String[] arr = s.split("@@@");

				cached_contexts.put(arr[0].trim(), arr[1].trim());

			}

			last_cache_update = DateUtils.now();

		}

		return cached_contexts;

	}