fr.aliasource.webmail.server.calendar.CalendarProxyImpl.java Source code

Introduction

Here is the source code for fr.aliasource.webmail.server.calendar.CalendarProxyImpl.java

Source

/* ***** BEGIN LICENSE BLOCK *****
 * Version: GPL 2.0
 *
 * The contents of this file are subject to the GNU General Public
 * License Version 2 or later (the "GPL").
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Initial Developer of the Original Code is
 *   MiniG.org project members
 *
 * ***** END LICENSE BLOCK ***** */

package fr.aliasource.webmail.server.calendar;

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

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

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.params.HttpConnectionManagerParams;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.google.gwt.core.client.GWT;

import fr.aliasource.webmail.server.FrontEndConfig;
import fr.aliasource.webmail.server.proxy.client.IAccount;

/**
 * Proxies requests to backend calendar action
 * 
 * @author tom
 * 
 */
public class CalendarProxyImpl extends HttpServlet {

    private static final long serialVersionUID = -5058309430406865212L;

    @SuppressWarnings("unused")
    private static final Log logger = LogFactory.getLog(CalendarProxyImpl.class);

    private String backendUrl;

    private HttpClient hc;

    @SuppressWarnings("unchecked")
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        IAccount ac = (IAccount) req.getSession().getAttribute("account");

        if (ac == null) {
            GWT.log("Account not found in session", null);
            resp.setStatus(HttpServletResponse.SC_FORBIDDEN);
            return;
        }

        PostMethod pm = new PostMethod(backendUrl);
        if (req.getQueryString() != null) {
            pm.setQueryString(req.getQueryString());
        }
        Map<String, String[]> params = req.getParameterMap();
        for (String p : params.keySet()) {
            String[] val = params.get(p);
            pm.setParameter(p, val[0]);
        }

        synchronized (hc) {
            try {
                int ret = hc.executeMethod(pm);
                if (ret != HttpStatus.SC_OK) {
                    log("method failed:\n" + pm.getStatusLine() + "\n" + pm.getResponseBodyAsString());
                    resp.setStatus(ret);
                } else {
                    InputStream is = pm.getResponseBodyAsStream();
                    transfer(is, resp.getOutputStream(), false);
                }
            } catch (Exception e) {
                log("error occured on call proxyfication", e);
            } finally {
                pm.releaseConnection();
            }
        }
    }

    private HttpClient createHttpClient() {
        HttpClient ret = new HttpClient(new MultiThreadedHttpConnectionManager());
        HttpConnectionManagerParams mp = ret.getHttpConnectionManager().getParams();
        mp.setDefaultMaxConnectionsPerHost(4);
        mp.setMaxTotalConnections(8);
        return ret;
    }

    /**
     * Fast stream transfer method
     * 
     * @param in
     * @param out
     * @throws IOException
     */
    public static void transfer(InputStream in, OutputStream out, boolean closeIn) throws IOException {
        final byte[] buffer = new byte[4096];

        try {
            while (true) {
                int amountRead = in.read(buffer);
                if (amountRead == -1) {
                    break;
                }
                out.write(buffer, 0, amountRead);
            }
        } finally {
            if (closeIn) {
                in.close();
            }
            out.flush();
            out.close();
        }
    }

    @Override
    public void init() throws ServletException {
        super.init();

        Map<String, String> prefs = new FrontEndConfig().get();
        backendUrl = prefs.get("frontend.proxyUrl") + "/calendar.do";
        this.hc = createHttpClient();
    }

}