com.google.sampling.experiential.server.migration.MigrationFrontendServlet.java Source code

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Here is the source code for com.google.sampling.experiential.server.migration.MigrationFrontendServlet.java

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/*
 * Copyright 2011 Google Inc. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance  with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package com.google.sampling.experiential.server.migration;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.SocketTimeoutException;
import java.net.URL;
import java.util.logging.Logger;

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

import org.joda.time.DateTime;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;

import com.google.appengine.api.modules.ModulesServiceFactory;
import com.google.appengine.api.users.User;
import com.google.appengine.api.utils.SystemProperty;
import com.google.sampling.experiential.server.AuthUtil;
import com.google.sampling.experiential.server.EnvironmentUtil;
import com.google.sampling.experiential.server.PacoModule;
import com.pacoapp.paco.shared.util.TimeUtil;

/**
 * Servlet that handles migration tasks for data
 *
 */
@SuppressWarnings("serial")
public class MigrationFrontendServlet extends HttpServlet {

    public static final Logger log = Logger.getLogger(MigrationFrontendServlet.class.getName());

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("application/json;charset=UTF-8");

        User user = AuthUtil.getWhoFromLogin();
        if (user == null) {
            AuthUtil.redirectUserToLogin(req, resp);
        } else if (AuthUtil.isUserAdmin()) {
            String cursor = null;
            DateTime stDate = null;
            DateTime endDate = null;
            cursor = req.getParameter("cursor");
            String jobName = req.getParameter("name");
            String startTime = req.getParameter("startTime");
            String endTime = req.getParameter("endTime");
            try {
                DateTimeFormatter formatter = DateTimeFormat.forPattern(TimeUtil.DATE_TIME_WITH_NO_TZ);
                if (startTime != null && endTime != null) {
                    stDate = formatter.parseDateTime(startTime);
                    endDate = formatter.parseDateTime(endTime);
                }
            } catch (IllegalArgumentException e) {
                resp.sendError(HttpServletResponse.SC_BAD_REQUEST);
            }
            String jobId = sendMigrateRequestToBackend(req, jobName, cursor, stDate, endDate);
            String redirectUrl = null;
            // On dev local, when we kick off job from backend module - migration with correct port number, 
            // the job status which is defined in default module is getting searched in migration module.
            // In other environments, the request gets routed through dispatch xml.
            if (EnvironmentUtil.isDevInstance()) {
                redirectUrl = "http://"
                        + ModulesServiceFactory.getModulesService().getVersionHostname("default", null)
                        + "/jobStatus?jobId=" + jobId;
            } else {
                redirectUrl = "/jobStatus?jobId=" + jobId;
            }
            resp.sendRedirect(redirectUrl);
        } else {
            resp.sendError(403);
        }
    }

    private String sendMigrateRequestToBackend(HttpServletRequest req, String jobName, String cursor,
            DateTime startDateTime, DateTime endDateTime) throws IOException {
        PacoModule pacoMod = new PacoModule("reportworker", req.getServerName());
        try {
            BufferedReader reader = null;
            try {
                reader = sendToBackend(pacoMod.getAddress(), jobName, cursor, startDateTime, endDateTime);
            } catch (SocketTimeoutException se) {
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e) {
                }
                reader = sendToBackend(pacoMod.getAddress(), jobName, cursor, startDateTime, endDateTime);
            }
            if (reader != null) {
                StringBuilder buf = new StringBuilder();
                String line;
                while ((line = reader.readLine()) != null) {
                    buf.append(line);
                }
                reader.close();
                return buf.toString();
            }
        } catch (MalformedURLException e) {
            log.severe("MalformedURLException: " + e.getMessage());
        }
        return null;
    }

    private BufferedReader sendToBackend(String backendAddress, String jobName, String cursor,
            DateTime startDateTime, DateTime endDateTime) throws MalformedURLException, IOException {
        URL url = null;
        String scheme = "https";
        HttpURLConnection connection = null;
        InputStreamReader inputStreamReader = null;
        BufferedReader reader = null;
        if (SystemProperty.environment.value() == SystemProperty.Environment.Value.Development) {
            scheme = "http";
        }
        StringBuffer urlBase = new StringBuffer(scheme + "://" + backendAddress + "/migrateBackend?who="
                + AuthUtil.getWhoFromLogin().getEmail().toLowerCase() + "&migrationName=" + jobName);
        if (cursor != null) {
            urlBase.append("&cursor=" + cursor);
        }
        if (startDateTime != null && endDateTime != null) {
            urlBase.append("&startTime=" + startDateTime + "&endTime=" + endDateTime);
        }
        url = new URL(urlBase.toString());
        log.info("URL to backend = " + url.toString());
        connection = (HttpURLConnection) url.openConnection();
        connection.setInstanceFollowRedirects(false);
        connection.setReadTimeout(10000);
        inputStreamReader = new InputStreamReader(connection.getInputStream());
        reader = new BufferedReader(inputStreamReader);
        return reader;
    }
}