de.thischwa.pmcms.server.ZipProxyServlet.java Source code

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Here is the source code for de.thischwa.pmcms.server.ZipProxyServlet.java

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/*******************************************************************************
 * Poor Man's CMS (pmcms) - A very basic CMS generating static html pages.
 * http://poormans.sourceforge.net
 * Copyright (C) 2004-2013 by Thilo Schwarz
 * 
 * == BEGIN LICENSE ==
 * 
 * Licensed under the terms of any of the following licenses at your
 * choice:
 * 
 *  - GNU Lesser General Public License Version 2.1 or later (the "LGPL")
 *    http://www.gnu.org/licenses/lgpl.html
 * 
 *  - Mozilla Public License Version 1.1 or later (the "MPL")
 *    http://www.mozilla.org/MPL/MPL-1.1.html
 * 
 * == END LICENSE ==
 ******************************************************************************/
package de.thischwa.pmcms.server;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;

import de.thischwa.pmcms.tool.Utils;
import de.thischwa.pmcms.tool.compression.Zip;

/**
 * Proxy servlet which refers all requests to a zip file.<br>
 * Init parameters:
 * <ul>
 * <li><b>file</b> (required): Path to the zip file</li>
 * <li><b>zipPathToSkip</b> (optional): Path to skip inside the zip file.<br>
 * Should used only if the zip file has one path which contains all the rest!</li>
 * </ul>
 * 
 * @author Thilo Schwarz
 */
public class ZipProxyServlet extends AServlet {
    private static final Logger logger = Logger.getLogger(ZipProxyServlet.class);
    private static final long serialVersionUID = 1L;
    private String zipPathToSkip = null;
    private Map<String, ZipEntry> zipInfo;
    private ZipFile zipFile;

    @Override
    public void init(ServletConfig config) throws ServletException {
        zipPathToSkip = config.getInitParameter("zipPathToSkip");
        String fileParam = config.getInitParameter("file");
        if (StringUtils.isBlank(fileParam))
            throw new IllegalArgumentException("No file parameter found!");
        File file = null;
        zipInfo = new HashMap<String, ZipEntry>();
        try {
            file = new File(config.getInitParameter("file"));
            if (!file.exists()) {
                throw new ServletException(String.format("Zip-file not found: %s", file.getPath()));
            }
            zipFile = new ZipFile(file);
            Enumeration<? extends ZipEntry> entries = zipFile.entries();
            while (entries.hasMoreElements()) {
                ZipEntry ze = entries.nextElement();
                String entryName = ze.getName();
                if (zipPathToSkip != null)
                    entryName = entryName.substring(zipPathToSkip.length() + 1);
                if (entryName.startsWith("/"))
                    entryName = entryName.substring(1);
                zipInfo.put(entryName, ze);
            }
            logger.debug("Found entries in zip: " + zipInfo.size());
        } catch (IOException e) {
            throw new ServletException("Couldn't read the zip file: " + e.getMessage(), e);
        }
        logger.info(String.format("ZipProxyServlet initialzed with file [%s] and path to skip [%s]", file.getPath(),
                zipPathToSkip));
    }

    @Override
    protected void doRequest(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        String reqPath = req.getPathInfo();
        if (reqPath.startsWith("/"))
            reqPath = reqPath.substring(1);

        ZipEntry entry = zipInfo.get(reqPath);
        if (entry == null) {
            logger.debug(Utils.join("Requested path not found: [", reqPath, "]"));
            resp.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        }
        logger.debug(Utils.join("Requested path: [", reqPath, "]"));

        ServletUtils.establishContentType(reqPath, resp);

        InputStream in = null;
        try {
            in = new BufferedInputStream(zipFile.getInputStream(entry));
            IOUtils.copy(in, resp.getOutputStream());
            logger.debug("Rendered: " + reqPath);
        } catch (FileNotFoundException e) {
            logger.error("zipped resource not found: " + reqPath);
        } finally {
            IOUtils.closeQuietly(in);
        }
    }

    @Override
    public void destroy() {
        super.destroy();
        Zip.closeQuietly(zipFile);
    }
}