view flys-client/src/main/java/de/intevation/flys/client/server/FixingsKMChartServiceImpl.java @ 3497:88feb3347aa5

Implement a ProxyServlet Implement a ProxyServlet to be able to restrict the access to the mapserver too. All queries to the provided map services should go throught this new ProxyServlet. Currently the ProxyServlet can only handle HTTP GET requests. flys-client/trunk@5221 c6561f87-3c4e-4783-a992-168aeb5c3f6f
author Bjoern Ricks <bjoern.ricks@intevation.de>
date Thu, 16 Aug 2012 14:42:36 +0000
parents 51ed89b754ae
children
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package de.intevation.flys.client.server;

import de.intevation.artifacts.common.utils.XMLUtils;

import de.intevation.artifacts.httpclient.http.HttpClient;
import de.intevation.artifacts.httpclient.http.HttpClientImpl;

import de.intevation.artifacts.httpclient.exceptions.ConnectionException;

import de.intevation.artifacts.httpclient.http.response.StreamResponseHandler;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

public class FixingsKMChartServiceImpl
extends      HttpServlet
{
    private static final Logger log =
        Logger.getLogger(FixingsKMChartServiceImpl.class);

    public static final String SERVICE_NAME = "fixings-km-chart";

    public FixingsKMChartServiceImpl() {
    }

    public void doGet(HttpServletRequest req, HttpServletResponse resp) {

        log.info("FixingsKMChartServiceImpl.doGet");

        String url    = getServletContext().getInitParameter("server-url");
        String locale = req.getParameter("locale");
        String filter = req.getParameter("filter");

        if (filter == null || filter.length() == 0) {
            log.warn("Missing 'filter' parameter.");
            return;
        }

        if (locale == null || locale.length() == 0) {
            locale = "de";
        }

        Document filterDoc = XMLUtils.jsonToXML(filter);

        if (filterDoc == null) {
            log.warn("Creating filter document failed.");
            return;
        }

        InputStream in;

        try {
            HttpClient client = new HttpClientImpl(url, locale);
            in = (InputStream)client.callService(
                url, // XXX: Why? The URL is passed by construction already.
                SERVICE_NAME,
                filterDoc,
                new StreamResponseHandler());
        }
        catch (ConnectionException ce) {
            log.error(ce);
            return;
        }

        resp.setHeader("Content-Type", guessMIMEType(filterDoc));

        try {
            OutputStream out = resp.getOutputStream();

            byte [] buf = new byte[4096];
            int i = -1;
            while ((i = in.read(buf)) >= 0) {
                out.write(buf, 0, i);
            }
            out.flush();
        }
        catch (IOException ioe) {
            log.error(ioe);
        }
        finally {
            try { in.close(); }
            catch (IOException ioe) { /* ignored */ }
        }
    }

    protected static String guessMIMEType(Document document) {

        NodeList formats = document.getElementsByTagName("format");

        String format = "png";

        if (formats.getLength() > 0) {
            String type = ((Element)formats.item(0)).getAttribute("type");
            if (type.length() > 0) {
                format = type;
            }
        }

        return "image/" + format;
    }
}
// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :

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