D-Net

package eu.dnetlib.data.search.app;

import eu.dnetlib.api.enabling.ISLookUpService;

import eu.dnetlib.api.enabling.ISRegistryService;

import eu.dnetlib.enabling.tools.blackboard.BlackboardJob;

import eu.dnetlib.enabling.tools.blackboard.BlackboardNotificationHandler;

import eu.dnetlib.enabling.tools.blackboard.BlackboardServerHandler;

import gr.uoa.di.driver.util.ServiceLocator;

import org.apache.log4j.Logger;

import org.w3c.dom.Document;

import org.w3c.dom.Node;

import org.xml.sax.InputSource;

import org.xml.sax.SAXException;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.dom.DOMSource;

import javax.xml.transform.stream.StreamResult;

import javax.xml.xpath.*;

import java.io.IOException;

import java.io.StringReader;

import java.io.StringWriter;

public class SearchServiceBlackboardHandler extends

        BlackboardNotificationHandler<BlackboardServerHandler> {

    private static Logger logger = Logger.getLogger(SearchServiceBlackboardHandler.class);

    private SearchServiceImpl searchService = null;

    private ServiceLocator<ISLookUpService> lookUpServiceServiceLocator = null;

    private ServiceLocator<ISRegistryService> registryServiceServiceLocator = null;

    private XPathExpression indexMdFormatExpression = null;

    private XPathExpression indexLayoutExpression = null;

    private XPathExpression searchMdFormatExpression = null;

    public SearchServiceBlackboardHandler() throws XPathExpressionException {

        XPathFactory factory = XPathFactory.newInstance();

        XPath xpath = factory.newXPath();

        indexMdFormatExpression = xpath.compile("//METADATA_FORMAT");

        indexLayoutExpression = xpath.compile("//METADATA_FORMAT_LAYOUT");

        searchMdFormatExpression = xpath.compile("//SERVICE_PROPERTIES/PROPERTY[@key='mdformat']");

    }

    @Override

    protected void processJob(BlackboardJob job) {

        logger.info("Got Blackboard Message");

        String action = job.getAction();

        try {

            getBlackboardHandler().ongoing(job);

            if (action.equals("UpdateIndex")) {

                String indexProfileId = job.getParameters().get("IndexId");

                logger.info("Updating the service to use index " + indexProfileId);

                String indexProfile = lookUpServiceServiceLocator.getService().getResourceProfile(indexProfileId);

                String mdFormat = getMDFormat(indexProfile);

                String indexLayout = getIndexLayout(indexProfile);

                logger.info("New mdFormat: " + mdFormat + ", new layout: " + indexLayout);

                searchService.setMdFormat(mdFormat);

                searchService.setIndexLayout(indexLayout);

                String searchProfileId = searchService.getServiceEPR().getParameter("serviceId");

                updateSearchServiceProfile(searchProfileId, mdFormat);

            } else {

                throw new Exception("Don't know what to do with " + action);

            }

            getBlackboardHandler().done(job);

        } catch (Exception e) {

            getBlackboardHandler().failed(job, e);

            logger.error("Error processing job", e);

        }

    }

    private String getIndexLayout(String indexProfile) throws ParserConfigurationException, IOException, SAXException, XPathExpressionException {

        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

        dbf.setNamespaceAware(true);

        DocumentBuilder db = dbf.newDocumentBuilder();

        Document doc = db.parse(new InputSource(new StringReader(indexProfile)));

        Node layoutNode = (Node) indexLayoutExpression.evaluate(doc, XPathConstants.NODE);

        return layoutNode.getTextContent();

    }

    private String getMDFormat(String indexProfile) throws ParserConfigurationException, IOException, SAXException, XPathExpressionException {

        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

        dbf.setNamespaceAware(true);

        DocumentBuilder db = dbf.newDocumentBuilder();

        Document doc = db.parse(new InputSource(new StringReader(indexProfile)));

        Node layoutNode = (Node) indexMdFormatExpression.evaluate(doc, XPathConstants.NODE);

        return layoutNode.getTextContent();

    }

    private void updateSearchServiceProfile(String searchProfileId, String mdFormat)  {

        try {

            String searchProfile = lookUpServiceServiceLocator.getService().getResourceProfile(searchProfileId);

            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

            dbf.setNamespaceAware(true);

            DocumentBuilder db = dbf.newDocumentBuilder();

            Document doc = db.parse(new InputSource(new StringReader(searchProfile)));

            Node node = (Node) searchMdFormatExpression.evaluate(doc,XPathConstants.NODE);

            node.getAttributes().getNamedItem("value").setNodeValue(mdFormat);

            DOMSource domSource = new DOMSource(doc);

            StringWriter writer = new StringWriter();

            StreamResult result = new StreamResult(writer);

            TransformerFactory tf = TransformerFactory.newInstance();

            Transformer transformer = tf.newTransformer();

            transformer.transform(domSource, result);

            registryServiceServiceLocator.getService().updateProfile(searchProfileId, writer.toString(), "SearchServiceResourceType");

        } catch (Exception e) {

            logger.error("Fail to update search service profile with id " + searchProfileId, e);

        }

        logger.info("Updated search service profile with id " +searchProfileId);

    }

    public ServiceLocator<ISLookUpService> getLookUpServiceServiceLocator() {

        return lookUpServiceServiceLocator;

    }

    public void setLookUpServiceServiceLocator(ServiceLocator<ISLookUpService> lookUpServiceServiceLocator) {

        this.lookUpServiceServiceLocator = lookUpServiceServiceLocator;

    }

    public void setRegistryServiceServiceLocator(ServiceLocator<ISRegistryService> registryServiceServiceLocator) {

        this.registryServiceServiceLocator = registryServiceServiceLocator;

    }

    public SearchServiceImpl getSearchService() {

        return searchService;

    }

    public void setSearchService(SearchServiceImpl searchService) {

        this.searchService = searchService;

    }

}