Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A class represents a file log for the index events.

 *    Copyright: 2013 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Jing Tao

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

package edu.ucsb.nceas.metacat.index.event;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.text.DateFormat;

import java.text.ParseException;

import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.List;

import java.util.Vector;

import org.apache.commons.io.FileUtils;

import org.apache.commons.io.IOUtils;

import org.dataone.configuration.Settings;

import org.dataone.service.types.v1.Identifier;

/**

 * A class represents a file log for the index events.

 * @author tao

 *

 */

public class IndexEventFileLog implements IndexEventLog {

    private static final String FIELDSEPERATOR = " ";

    private static final String LOGFILENAME = "solr-index.log";

    private static final String LASTPROCESSEDDATEFILENAME = "solr-last-proccessed-date";

    private File logFile = null;

    private File lastProcessedDateFile = null;

    private long index=1;

    private SimpleDateFormat format = new SimpleDateFormat();

    /**

     * Constructor. Initialize the log file. The log file locates solr.homeDir. 

     * If the solr.homeDir doesn't exists in the metacat.properties, the it will locate the user's home directory.

     * @throws IOException 

     */

    public IndexEventFileLog() throws IOException {

        String path = Settings.getConfiguration().getString("solr.homeDir");

        if(path == null || path.trim().equals("")) {

            path = System.getProperty("user.home");

        }

        File pathDir = new File(path);

        if(!pathDir.exists()) {

            pathDir.mkdirs();

        }

        logFile = new File(pathDir, LOGFILENAME);

        if(!logFile.exists()) {

            logFile.createNewFile();

        }

        lastProcessedDateFile = new File(pathDir, LASTPROCESSEDDATEFILENAME);

        if(!lastProcessedDateFile.exists()) {

            lastProcessedDateFile.createNewFile();

        }

    }

    /**

     * Write an IndexEvent into a file

     * @param event

     * @return the serial number for this event

     * @throws IndexEventLogException

     */

    public synchronized long write(IndexEvent event) throws IndexEventLogException {

        if(event != null) {

            Vector<String> lines = new Vector<String>();

            StringBuffer lineBuffer = new StringBuffer();

            lineBuffer.append("\""+index+"\""+FIELDSEPERATOR);

            int type = event.getType();

            lineBuffer.append("\""+type+"\""+FIELDSEPERATOR);

            Date date = event.getDate();

            if(date != null) {

                DateFormat formate = new SimpleDateFormat();

                lineBuffer.append("\""+formate.format(date)+"\""+FIELDSEPERATOR);

            }

            Identifier id = event.getPid();

            if(id != null) {

                lineBuffer.append("\""+id.getValue()+"\""+FIELDSEPERATOR);

            }

            String description = event.getDescription();

            if(description != null) {

                lineBuffer.append("\""+description+"\""+FIELDSEPERATOR);

            }

            lines.add(lineBuffer.toString());

            String lineEnding = null;//null means to use the system default one.

            boolean append = true;

            try {

                FileUtils.writeLines(logFile, "UTF-8", lines, append);

                //FileUtils.writeLines(logFile, "UTF-8", lines, lineEnding);

                //IOUtils.writeLines(lines, lineEnding, new FileOutputStream(logFile), "UTF-8");

            } catch (FileNotFoundException e) {

                // TODO Auto-generated catch block

                throw new IndexEventLogException(e.getMessage());

            } catch (IOException e) {

                // TODO Auto-generated catch block

                throw new IndexEventLogException(e.getMessage());

            }

            index++;

        }

        return index;

    }

    /**

     * Gets the list of IndexEvent matching the specified set of filters. The filter parameters can be null

     * @param type  the type of the event

     * @param pid   the identifier of the data object in the event

     * @param start the start time of the time range for query

     * @param end   the end time of the time range for query

     * @return

     * @throws IndexEventLogException

     */

    public List<IndexEvent> getEvents(int type, Identifier pid, Date start, Date end) throws IndexEventLogException {

        List<IndexEvent> list = null;

        return list;

    }

    /**

     * Get the list of identifiers which were failed to build the solr index since the 

     * previous timed indexing (including the ones in the timed indexing).

     * @return the list of failure identifiers. The null will be returned if no failure. 

     */

    public List<String> getFailedPids() throws IndexEventLogException {

        return null;

    }

    /**

     * Get the latest SystemMetadata modification Date of the objects that were built

     * the solr index during the previous timed indexing process.

     * @return the date. The null will be returned if there is no such date.

     * @throws IndexEventLogException

     */

    public Date getLastProcessDate() throws IndexEventLogException {

        Date date = null;

        try {

            String dateStr = FileUtils.readFileToString(lastProcessedDateFile, "UTF-8");

            if(dateStr != null && !dateStr.trim().equals("")) {

                date = format.parse(dateStr);

            }

        } catch (IOException e) {

            throw new IndexEventLogException("IndexEventFileLog.getLastProcessedDate - couldn't read the last processed date :", e);

        } catch (ParseException e) {

            // TODO Auto-generated catch block

            throw new IndexEventLogException("IndexEventFileLog.getLastProcessedDate - couldn't read the last processed date since the content of file is not date :", e);

        }

        return date;

    }

    /**

     * Set the SystemMetadata modification Date of the objects that were built

     * the solr index during the previous timed indexing process.

     * @throws IndexEventLogException

     */

    public void setLastProcessDate(Date date) throws IndexEventLogException {

        String dateStr = format.format(date);

        try {

            FileUtils.writeStringToFile(lastProcessedDateFile, dateStr, "UTF-8");

        } catch (IOException e) {

            // TODO Auto-generated catch block

           throw new IndexEventLogException("IndexEventFileLog.setLastProcessedDate - couldn't set the last processed date :", e);

        }

    }

}