com.google.cloud.backend.spi.ProspectiveSearchServlet.java Source code

Introduction

Here is the source code for com.google.cloud.backend.spi.ProspectiveSearchServlet.java

Source

/*
 * Copyright (c) 2013 Google Inc.
 *
 * 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.cloud.backend.spi;

import com.google.android.gcm.server.Message;
import com.google.android.gcm.server.Result;
import com.google.android.gcm.server.Sender;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.prospectivesearch.ProspectiveSearchServiceFactory;
import com.google.cloud.backend.config.BackendConfigManager;
import com.google.cloud.backend.pushnotification.Utility;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.logging.Logger;

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

import org.json.JSONObject;

/**
 * A servlet class for handling Prospective Search API tasks.
 */
@SuppressWarnings("serial")
public class ProspectiveSearchServlet extends HttpServlet {

    private static final int GCM_SEND_RETRIES = 3;

    private static final Logger log = Logger.getLogger(ProspectiveSearchServlet.class.getName());

    private static final BackendConfigManager backendConfigManager = new BackendConfigManager();

    private static final DeviceSubscription deviceSubscription = new DeviceSubscription();

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        // Return if push notification is not enabled
        if (!backendConfigManager.isPushEnabled()) {
            log.info("ProspectiveSearchServlet: couldn't send push notification because it is disabled.");
            return;
        }

        // dispatch GCM messages to each subscribers
        String[] subIds = req.getParameterValues("id");
        // Each subId has this format "<regId>:query:<clientSubId>"
        for (String subId : subIds) {
            String regId = SubscriptionUtility.extractRegId(subId);
            if (isSubscriptionActive(regId)) {
                Entity matchedEntity = ProspectiveSearchServiceFactory.getProspectiveSearchService()
                        .getDocument(req);
                if (matchedEntity != null) {
                    log.info(String.format(
                            "ProspectiveSearchServlet: matchedEntity.toString: " + matchedEntity.toString()));
                } else {
                    log.info(String.format("ProspectiveSearchServlet: matchedEntity is null."));
                }

                sendPushNotification(regId, subId, matchedEntity);
            } else {
                SubscriptionUtility.clearSubscriptionAndDeviceEntity(Arrays.asList(regId));
            }
        }

    }

    private void sendPushNotification(String regId, String subId, Entity matchedEntity) throws IOException {
        SubscriptionUtility.MobileType type = SubscriptionUtility.getMobileType(subId);

        if (SubscriptionUtility.MobileType.ANDROID == type) {
            sendGcmAlert(subId, regId, matchedEntity);
        } else if (SubscriptionUtility.MobileType.IOS == type) {
            sendIosAlert(subId, new String[] { regId }, matchedEntity);
        }
    }

    /**
     * Checks if subscriptions for the device are active.
     *
     * @param deviceId A unique device identifier
     * @return True, if subscriptions are active; False, the otherwise
     */
    private boolean isSubscriptionActive(String deviceId) {
        Date lastDeleteAll = backendConfigManager.getLastSubscriptionDeleteAllTime();
        // If the admin never requested to delete all subscriptions, then this device subscription is
        // still active.
        if (lastDeleteAll == null) {
            return true;
        }

        Entity deviceEntity = deviceSubscription.get(deviceId);
        if (deviceEntity == null) {
            return false;
        }
        Date latestSubscriptionTime = (Date) deviceEntity.getProperty(DeviceSubscription.PROPERTY_TIMESTAMP);

        return latestSubscriptionTime.after(lastDeleteAll);
    }

    private void sendGcmAlert(String subId, String regId, Entity matchedEntity) throws IOException {
        String gcmKey = backendConfigManager.getGcmKey();
        boolean isGcmKeySet = !(gcmKey == null || gcmKey.trim().length() == 0);

        // Only attempt to send GCM if GcmKey is available
        if (isGcmKeySet) {
            Sender sender = new Sender(gcmKey);

            if (matchedEntity != null) {
                Message message = new Message.Builder().addData(SubscriptionUtility.GCM_KEY_SUBID, subId)
                        .addData("data.message", (String) matchedEntity.getProperty("message"))
                        .addData("data.updatedBy", (String) matchedEntity.getProperty("_updatedBy"))
                        .addData("data.owner", (String) matchedEntity.getProperty("_owner"))
                        .addData("data.sound", "new_message")
                        //extra data.<key> elements can be added here
                        .build();

                Result r = sender.send(message, regId, GCM_SEND_RETRIES);
                if (r.getMessageId() != null) {
                    log.info("ProspectiveSearchServlet: GCM sent: subId: " + subId);
                } else {
                    log.warning("ProspectiveSearchServlet: GCM error for subId: " + subId + ", senderId: " + gcmKey
                            + ", error: " + r.getErrorCodeName());
                    ArrayList<String> deviceIds = new ArrayList<String>();
                    deviceIds.add(regId);
                    SubscriptionUtility.clearSubscriptionAndDeviceEntity(deviceIds);
                }
            }
        } else {
            // Otherwise, just write a log entry
            log.info(String.format("ProspectiveSearchServlet: GCM is not sent: GcmKey: %s ", isGcmKeySet));
        }
    }

    private void sendIosAlert(String subId, String[] deviceTokens, Entity matchedEntity) {
        //TODO consider using the matchedEntity.
        log.info("Sending iOS push alert to backend");
        Utility.enqueuePushAlert(subId, deviceTokens);
        log.info("Push alert enqueued successfully");
    }
}