D-Net

package eu.dnetlib.index;

import java.io.StringReader;

import java.util.List;

import java.util.concurrent.Executor;

import java.util.concurrent.Executors;

import eu.dnetlib.clients.index.utils.MetadataReference;

import eu.dnetlib.clients.index.utils.MetadataReferenceFactory;

import eu.dnetlib.clients.index.utils.ServiceTools;

import eu.dnetlib.enabling.actions.AbstractSubscriptionAction;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.dom4j.Document;

import org.dom4j.DocumentException;

import org.dom4j.Element;

import org.dom4j.Node;

import org.dom4j.io.SAXReader;

import org.springframework.beans.factory.annotation.Autowired;

/**

 * MdFormatNotificationHandler updates index schema in response to metadata formats modifications.

 *

 * @author claudio

 */

public class MdFormatNotificationHandler extends AbstractSubscriptionAction {

	/**

	 * Logger.

	 */

	private static final Log log = LogFactory.getLog(MdFormatNotificationHandler.class); // NOPMD by marko on 11/24/08 5:02 PM

	private final transient ThreadLocal<SAXReader> domFactory = new ThreadLocal<SAXReader>() {

		@Override

		protected SAXReader initialValue() {

			return new SAXReader();

		}

	};

	@Autowired

	private transient MetadataReferenceFactory mdFactory;

	@Autowired

	private IndexServerDAOMap indexServerDAOMap;

	@Autowired

	private ServiceTools serviceTools;

	private Executor executor = Executors.newSingleThreadExecutor();

	/**

	 * {@inheritDoc}

	 */

	private boolean enabled;

	@Override

	public void notified(final String subscrId, final String topic, final String rsId, final String profile) {

		if (!topic.startsWith(getTopicPrefix())) return;

		executor.execute(() -> {

			try {

				final Document doc = parse(profile);

				final Node formatNode = doc.selectSingleNode("//CONFIGURATION/NAME/text()");

				if ((formatNode != null) && !formatNode.asXML().isEmpty()) {

					final String format = formatNode.asXML();

					final Iterable<Element> layouts = (Iterable<Element>) doc.selectNodes("//STATUS/LAYOUTS/LAYOUT");

					final Node interpretationNode = doc.selectSingleNode("//CONFIGURATION/INTERPRETATION/text()");

					final String interpretation = interpretationNode.asXML();

					log.info("found a change in mdFormat: " + format);

					for (Element element : layouts) {

						final String layout = element.attributeValue("name");

						// updates index schema based on mdFormat and layout

						final MetadataReference mdRef = mdFactory.getMetadata(format, layout, interpretation);

						final Document fields = parse(element.selectSingleNode("./FIELDS").asXML());

						List<String> backends = serviceTools.getBackendIds(mdRef);

						if ((backends == null) || backends.isEmpty()) {

							log.warn("There is no backendId in profiles for mdref " + mdRef);

						}

						for (String backendId : backends) {

							IndexServerDAO idxDao = indexServerDAOMap.getIndexServerDAO(backendId);

							if (idxDao == null) throw new RuntimeException("No index found for the mdformat " + mdRef);

							log.info("Found index DAO which serve this mdFormat");

							idxDao.updateIndexCollection(mdRef, fields);

						}

					}

				}

				log.info("Upload schema completed");

			} catch (Exception e) {

				throw new RuntimeException(e); // NOPMD

			}

		});

	}

	/**

	 * Helper method, parses an xml string.

	 *

	 * @param source the xml.

	 * @return the parsed xml.

	 * @throws DocumentException could happen

	 */

	private Document parse(final String source) throws DocumentException {

		return domFactory.get().read(new StringReader(source));

	}

}