doug.iotdemo.analyzer.Analyzer.java Source code

Introduction

Here is the source code for doug.iotdemo.analyzer.Analyzer.java

Source

/*******************************************************************************
 * Copyright (c) 2016 QNX Software Systems and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *******************************************************************************/
package doug.iotdemo.analyzer;

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardCopyOption;
import java.util.HashMap;
import java.util.Map;

import org.eclipse.paho.client.mqttv3.MqttException;

import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.model.AttributeAction;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.AttributeValueUpdate;
import com.amazonaws.services.dynamodbv2.model.ScanRequest;
import com.amazonaws.services.dynamodbv2.model.ScanResult;
import com.amazonaws.services.dynamodbv2.model.UpdateItemRequest;
import com.amazonaws.services.sqs.AmazonSQS;
import com.amazonaws.services.sqs.AmazonSQSClient;
import com.amazonaws.services.sqs.model.Message;
import com.amazonaws.services.sqs.model.ReceiveMessageResult;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

import doug.iotdemo.common.AmazonUtils;
import doug.iotdemo.common.MQTTUtils;

public class Analyzer {

    private Map<String, SensorData> data = new HashMap<>();
    private AmazonDynamoDB db = new AmazonDynamoDBClient();
    private MQTTUtils mqtt;

    public static void main(String[] args) {
        try {
            new Analyzer().run();
        } catch (Throwable e) {
            e.printStackTrace();
        }
    }

    public Analyzer() throws MqttException, IOException {
        Path certPath = Files.createTempFile("cert", ".jks");
        InputStream certIn = getClass().getResourceAsStream("/analyzer.jks");
        Files.copy(certIn, certPath, StandardCopyOption.REPLACE_EXISTING);
        System.setProperty("javax.net.ssl.keyStore", certPath.toString());
        System.setProperty("javax.net.ssl.keyStorePassword", "password");

        mqtt = new MQTTUtils();
    }

    void run() throws IOException, MqttException {
        System.out.println("Doing initial scan");
        doInitialScan();
        System.out.println("Done");

        String url = AmazonUtils.getTimeQueueURL();
        AmazonSQS sqs = new AmazonSQSClient();
        while (true) {
            ReceiveMessageResult msgResult = sqs.receiveMessage(url);
            for (Message msg : msgResult.getMessages()) {
                JsonObject request = new JsonParser().parse(msg.getBody()).getAsJsonObject();
                String sensor = request.get("sensor").getAsString();
                long time = request.get("time").getAsLong();
                addTime(sensor, time);
                saveSensor(sensor);
                sqs.deleteMessage(url, msg.getReceiptHandle());
            }
        }
    }

    void doInitialScan() throws IOException, MqttException {
        // Load up our data
        Map<String, AttributeValue> lastKeyEvaluated = null;
        do {
            ScanRequest request = new ScanRequest().withTableName(AmazonUtils.getTimeTableName())
                    .withAttributesToGet("sensor", "time").withExclusiveStartKey(lastKeyEvaluated);
            ScanResult result = db.scan(request);
            for (Map<String, AttributeValue> item : result.getItems()) {
                String sensor = item.get("sensor").getS();
                int time = Integer.valueOf(item.get("time").getN());
                addTime(sensor, time);
            }
            lastKeyEvaluated = result.getLastEvaluatedKey();
        } while (lastKeyEvaluated != null);

        // Save a snapshot for each sensor
        for (String sensor : data.keySet()) {
            saveSensor(sensor);
        }
    }

    void addTime(String sensor, long time) {
        SensorData sensorData = data.get(sensor);
        if (sensorData == null) {
            sensorData = new SensorData();
            data.put(sensor, sensorData);
        }

        sensorData.time += time;
        sensorData.count++;
    }

    void saveSensor(String sensor) throws IOException, MqttException {
        SensorData sensorData = data.get(sensor);
        if (sensorData != null) {
            UpdateItemRequest request = new UpdateItemRequest().withTableName(AmazonUtils.getSensorTableName())
                    .addKeyEntry("sensor", new AttributeValue().withS(sensor))
                    .addAttributeUpdatesEntry("time",
                            new AttributeValueUpdate()
                                    .withValue(new AttributeValue().withN(Long.toString(sensorData.time)))
                                    .withAction(AttributeAction.PUT))
                    .addAttributeUpdatesEntry("count",
                            new AttributeValueUpdate()
                                    .withValue(new AttributeValue().withN(Long.toString(sensorData.count)))
                                    .withAction(AttributeAction.PUT));
            db.updateItem(request);

            long thresh = sensorData.time / sensorData.count;
            mqtt.sendThreshold(sensor, thresh);
        }
    }

}