source: main/trunk/greenstone3/src/java/org/greenstone/gsdl3/service/CoverageMetadataRetrieve.java@ 22974

/*
 * MyNewServicesTemplate.java - a dummy class showing how to create new 
 * services for Greenstone3
 *
 * This class has two dummy services: TextQuery and MyDifferentService
 */

// This file needs to be put in org/greenstone/gsdl3/service
package org.greenstone.gsdl3.service;

// Greenstone classes
import org.greenstone.gsdl3.util.*;

// XML classes
import org.w3c.dom.Document;
import org.w3c.dom.Element; 
import org.w3c.dom.NodeList;

import org.apache.log4j.*;

import java.util.Iterator;
import java.util.Vector;
import java.util.Set;

// change the class name (and the filename) to something more appropriate
public class CoverageMetadataRetrieve 
    extends ServiceRack {

    // add in a logger for error messages
    static Logger logger = Logger.getLogger("CoverageMetadataRetrieve");

    protected SimpleCollectionDatabase coll_db = null;
    protected String index_stem = null;


    // the new service names
    protected static final String COVERAGE_SERVICE = "CoverageMetadataRetrieve";

    // initialize any custom variables
    public CoverageMetadataRetrieve() {

    }

    // clean up anything that we need to 
    public void cleanUp() {
    super.cleanUp();
    }
    
    // Configure the class based in info in buildConfig.xml and collectionConfig.xml
    // info is the <serviceRack name="MyNewServicesTemplate"/> element from
    // buildConfig.xml, and extra_info is the whole collectionConfig.xml file
    // in case its needed
    public boolean configure(Element info, Element extra_info) {

    if (!super.configure(info, extra_info)) {
        return false;
    }

    logger.info("Configuring CoverageMetadataRetrieve...");

    // set up short_service_info - this currently is a list of services, 
    // with their names and service types
    // we have two services, a new textquery, and a new one of a new type
    //Element tq_service = this.doc.createElement(GSXML.SERVICE_ELEM);
    //tq_service.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_QUERY);
    //tq_service.setAttribute(GSXML.NAME_ATT, QUERY_SERVICE);
    //this.short_service_info.appendChild(tq_service);

    Element diff_service = this.doc.createElement(GSXML.SERVICE_ELEM);
    diff_service.setAttribute(GSXML.TYPE_ATT, "retrieve");
    diff_service.setAttribute(GSXML.NAME_ATT, COVERAGE_SERVICE);
    this.short_service_info.appendChild(diff_service);

    // the index stem is either specified in the config file or is  the collection name
    Element index_stem_elem = (Element) GSXML.getChildByTagName(info, GSXML.INDEX_STEM_ELEM);
    if (index_stem_elem != null) {
        this.index_stem = index_stem_elem.getAttribute(GSXML.NAME_ATT);
    }
    if (this.index_stem == null || this.index_stem.equals("")) {
        logger.error("CoverageMetadataRetrieve.configure(): indexStem element not found, stem will default to collection name");
        this.index_stem = this.cluster_name;
    }

    // find out what kind of database we have
    Element database_type_elem = (Element) GSXML.getChildByTagName(info, GSXML.DATABASE_TYPE_ELEM);
    String database_type = null;
    if (database_type_elem != null) {
      database_type = database_type_elem.getAttribute(GSXML.NAME_ATT);
    }
    if (database_type == null || database_type.equals("")) {
      database_type = "gdbm"; // the default
    }
    coll_db = new SimpleCollectionDatabase(database_type);
    if (!coll_db.databaseOK()) {
      logger.error("Couldn't create the collection database of type "+database_type);
      return false;
    }

    // Open database for querying
    String coll_db_file = GSFile.collectionDatabaseFile(this.site_home, this.cluster_name, this.index_stem, database_type);
    if (!this.coll_db.openDatabase(coll_db_file, SimpleCollectionDatabase.READ)) {
        logger.error("Could not open collection database!");
        return false;
    }


    // Extract any relevant information from info and extra_info
    // This can be used to set up variables.

    // If there is any formatting information, add it in to format_info_map
    
    // Do this for all services as appropriate
    Element format = null; // find it from info/extra_info
    if (format != null) {
        this.format_info_map.put(COVERAGE_SERVICE, this.doc.importNode(format, true));
    }

    return true;
    
    }

    // get the desription of a service. Could include parameter lists, displayText
    protected Element getServiceDescription(String service, String lang, String subset) {

    // check that we have been asked for the right service
    if (!service.equals(COVERAGE_SERVICE)) {
        return null;
    }

    /*
    if (service.equals(QUERY_SERVICE)) {
        Element tq_service = this.doc.createElement(GSXML.SERVICE_ELEM);
        tq_service.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_QUERY);
        tq_service.setAttribute(GSXML.NAME_ATT, QUERY_SERVICE);
        if (subset==null || subset.equals(GSXML.DISPLAY_TEXT_ELEM+GSXML.LIST_MODIFIER)) {
        // add in any <displayText> elements
        // name, for example - get from properties file
        tq_service.appendChild(GSXML.createDisplayTextElement(this.doc, GSXML.DISPLAY_TEXT_NAME, getTextString(QUERY_SERVICE+".name", lang) ));
        }
    
        if (subset==null || subset.equals(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER)) {
        // add in a param list if this service has parameters
        Element param_list = this.doc.createElement(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER);
        tq_service.appendChild(param_list);
        // create any params and append to param_list
        }
        return tq_service;
    } 
    */

    if (service.equals(COVERAGE_SERVICE)) {
        Element diff_service = this.doc.createElement(GSXML.SERVICE_ELEM);
        diff_service.setAttribute(GSXML.TYPE_ATT, "retrieve");
        diff_service.setAttribute(GSXML.NAME_ATT, COVERAGE_SERVICE);
        if (subset==null || subset.equals(GSXML.DISPLAY_TEXT_ELEM+GSXML.LIST_MODIFIER)) {
        // add in any <displayText> elements
        // name, for example - get from properties file
        diff_service.appendChild(GSXML.createDisplayTextElement(this.doc, GSXML.DISPLAY_TEXT_NAME, getTextString(COVERAGE_SERVICE+".name", lang) ));
        }
    
        if (subset==null || subset.equals(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER)) {
        // add in a param list if this service has parameters
        Element param_list = this.doc.createElement(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER);
        diff_service.appendChild(param_list);
        // create any params and append to param_list
        }

        return diff_service;
    } 
    
    // not a valid service for this class
    return null;
    


    }

    /** This is the method that actually handles the TextQuery Service */
    //protected Element processTextQuery(Element request) {

    //Element result = this.doc.createElement(GSXML.RESPONSE_ELEM);
    //result.setAttribute(GSXML.FROM_ATT, QUERY_SERVICE);
    //result.setAttribute(GSXML.TYPE_ATT, GSXML.REQUEST_TYPE_PROCESS);

    // fill in the rest
    //return result;
    //}

    /** This is the method that actually handles the MyDifferentService service */
    protected Element processCoverageMetadataRetrieve(Element request) {

    
    if (!this.coll_db.databaseOK()) {
    logger.error("No valid database found\n");
    return null;
    }

    DBInfo collection_info = this.coll_db.getInfo("collection");
    
    Set keys = collection_info.getKeys();

    Vector valid_keys = new Vector();

    // Iterate over keys and add valid ones to the valid_keys vector
    String current_key = null;
    Iterator iter = keys.iterator();

    while (iter.hasNext()) {
        current_key = (String) iter.next();
        if(current_key.matches("^metadatalist-([a-zA-Z][^-])*$"))
        {
            logger.error("********** ADDING " + current_key + " TO VALID KEYS LIST **********\n");
            valid_keys.add(current_key);
        }
    }
   
    // Create response
    Element result = this.doc.createElement(GSXML.RESPONSE_ELEM);
    result.setAttribute(GSXML.FROM_ATT, COVERAGE_SERVICE);
    result.setAttribute(GSXML.TYPE_ATT, GSXML.REQUEST_TYPE_PROCESS);

    Element metadataSetList = this.doc.createElement("metadataSetList");
    result.appendChild(metadataSetList);


    // Iterate over valid keys and build up response
    Element metadataSet = null;
    Element metadata = null;
    String value = null;
    String name = null;
    iter = valid_keys.iterator();

    while (iter.hasNext()) {
        current_key = (String) iter.next();

        // Create metadataSet using the current key and add to metadataSetList
        metadataSet = this.doc.createElement("metadataSet");
        if(current_key.indexOf("-") != -1)
        {
            name = current_key.split("-")[1];
        }
        metadataSet.setAttribute(GSXML.NAME_ATT, name);
        metadataSetList.appendChild(metadataSet);

        // Create a metadata element for each value and add to metadataSet
        Vector sub_info = collection_info.getMultiInfo(current_key);
        Iterator iter2 = sub_info.iterator();
        while (iter2.hasNext()) {
            value = (String) iter2.next();     
            metadata = this.doc.createElement("metadata");
            metadata.setAttribute(GSXML.NAME_ATT, value);
            metadataSet.appendChild(metadata);
        }

    }

    return result;

    }
}