com.google.sampling.experiential.server.PubExperimentServlet.java Source code

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Here is the source code for com.google.sampling.experiential.server.PubExperimentServlet.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;

import java.io.IOException;
import java.util.List;
import java.util.logging.Logger;

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

import org.joda.time.DateTimeZone;

import com.google.appengine.api.users.User;
import com.google.common.collect.Lists;
import com.pacoapp.paco.shared.comm.Outcome;

/**
 * Servlet that answers requests for experiments.
 *
 * Only used by the Android client to get the current list of experiments.
 *
 * @author Bob Evans
 *
 */
@SuppressWarnings("serial")
public class PubExperimentServlet extends HttpServlet {

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

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

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json;charset=UTF-8");

        DateTimeZone timezone = TimeUtil.getTimeZoneForClient(req);
        log.info("Timezone is computed to be: " + timezone.toString());
        logPacoClientVersion(req);

        User user = AuthUtil.getWhoFromLogin();
        String email = null;
        if (user != null) {
            email = AuthUtil.getEmailOfUser(req, user);
        } else {
            email = req.getRemoteAddr();
        }

        String selectedExperimentsParam = req.getParameter("id");

        String pacoProtocol = req.getHeader("pacoProtocol");
        if (pacoProtocol == null) {
            pacoProtocol = req.getParameter("pacoProtocol");
        }

        String experimentsJson = null;
        ExperimentServletHandler handler = null;
        if (selectedExperimentsParam != null) {
            handler = new ExperimentServletSelectedExperimentsFullLoadHandler(email, timezone,
                    selectedExperimentsParam, pacoProtocol);
        }
        if (handler != null) {
            log.info("Loading experiments...");
            experimentsJson = handler.performLoad();
            resp.getWriter().println(scriptBust(experimentsJson));
        } else {
            resp.getWriter().println(scriptBust("Unrecognized parameters!"));
        }
    }

    private void logPacoClientVersion(HttpServletRequest req) {
        String pacoVersion = req.getHeader("paco.version");
        if (pacoVersion != null) {
            log.info("Paco version of request = " + pacoVersion);
        }
    }

    private String scriptBust(String experimentsJson) {
        // TODO add scriptbusting prefix to this and client code.
        return experimentsJson;
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json;charset=UTF-8");
        DateTimeZone timezone = TimeUtil.getTimeZoneForClient(req);
        logPacoClientVersion(req);

        User user = AuthUtil.getWhoFromLogin();
        String email = null;
        if (user != null) {
            email = AuthUtil.getEmailOfUser(req, user);
        } else {
            email = req.getRemoteAddr();
        }

        processJsonUpload(req, resp, email);
    }

    private void processJsonUpload(HttpServletRequest req, HttpServletResponse resp, String email)
            throws IOException {
        String postBodyString;
        try {
            postBodyString = org.apache.commons.io.IOUtils.toString(req.getInputStream(), "UTF-8");
        } catch (IOException e) {
            log.info("IO Exception reading post data stream: " + e.getMessage());
            throw e;
        }
        if (postBodyString.equals("")) {
            throw new IllegalArgumentException("Empty Post body");
        }

        String appIdHeader = req.getHeader("http.useragent");
        String pacoVersion = req.getHeader("paco.version");
        log.info("Paco version = " + pacoVersion);

        String results = EventJsonUploadProcessor.create().processJsonEvents(postBodyString, email, appIdHeader,
                pacoVersion);
        resp.setContentType("application/json;charset=UTF-8");
        resp.getWriter().write(results);
    }

    public List<Outcome> createErrorOutcome(String msg) {
        Outcome outcome = new Outcome(0, msg);
        List<Outcome> outcomes = Lists.newArrayList(outcome);
        return outcomes;
    }

}