source: vlo/trunk/vlo_webapp/src/main/java/eu/clarin/cmdi/vlo/importer/NationalProjectPostProcessor.java @ 1886

package eu.clarin.cmdi.vlo.importer;

import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;

import eu.clarin.cmdi.vlo.Configuration;
import org.apache.commons.io.FileUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;

/**
 * Adds information about the affiliation of a metadata file to a national project (like CLARIN-X etc.) into facet nationalProject
 * @author Thomas Eckart
 *
 */
public class NationalProjectPostProcessor extends LanguageCodePostProcessor {
        private final static Logger LOG = LoggerFactory.getLogger(NationalProjectPostProcessor.class);

        //private static String mappingFileName = "nationalProjectsMapping.xml";
        private static Map<String, String> nationalProjectMap = null;

        /**
         * Returns the national project based on the mapping in Configuration.getNationalProjectMapUrl()
         * If no mapping was found empty String is returned
         * @return
         */
        @Override
    public String process(String value) {
        String result = value.trim();
        if (result != null && getMapping().containsKey(result)) {
            result = getMapping().get(result);
        } else {
                result = "";
        }
        return result;
    }

        private Map<String, String> getMapping() {
                if(nationalProjectMap == null)
                        nationalProjectMap = getNationalProjectMapping();
                return  nationalProjectMap;
        }

        private Map<String, String> getNationalProjectMapping() {
        String mappingFileName = Configuration.getInstance().getNationalProjectMapping();
                LOG.debug("Creating national project map.");
        try {
            Map<String, String> result = new HashMap<String, String>();
            DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
            domFactory.setNamespaceAware(true);

            File mappingFile = new File(mappingFileName);
            if(!mappingFile.exists()) {         // mapping file not accessible?
                LOG.info("National project mapping file does not exist - using minimal test file.");
                mappingFile = createMinimalMappingFile();
            }
            DocumentBuilder builder = domFactory.newDocumentBuilder();
            Document doc = builder.parse(mappingFile);
            XPath xpath = XPathFactory.newInstance().newXPath();
            NodeList nodeList = (NodeList) xpath.evaluate("//nationalProjectMapping", doc, XPathConstants.NODESET);
            for (int i = 1; i <= nodeList.getLength(); i++) {
                String mdCollectionDisplayName = xpath.evaluate("//nationalProjectMapping["+i+"]/MdCollectionDisplayName", doc).trim();
                String nationalProject = xpath.evaluate("//nationalProjectMapping["+i+"]/NationalProject", doc).trim();
                result.put(mdCollectionDisplayName, nationalProject);
            }
            return result;
        } catch (Exception e) {
            throw new RuntimeException("Cannot instantiate postProcessor:", e);
        }
        }

        /**
         * Create temporary and minimal mapping file for testing purposes and as backup solution
         * @return minimal file for national projects mapping (e.g. ANDES -> CLARIN-EU)
         */
        private File createMinimalMappingFile() {
                String content = "";
        content += "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n";
        content += "<nationalProjects>\n";
        content += "   <nationalProjectMapping><MdCollectionDisplayName>ANDES</MdCollectionDisplayName><NationalProject>CLARIN-EU</NationalProject></nationalProjectMapping>\n";
        content += "</nationalProjects>\n";

        File file = null;
        try {
                file = File.createTempFile("vlo.nationalTestMapping", ".map");
                FileUtils.writeStringToFile(file, content, "UTF-8");
        } catch (IOException ioe) {
                ioe.printStackTrace();
                LOG.error("Could not create temporary national project mapping file");
        }

        return file;
        }
}