sonata.kernel.WimAdaptor.messaging.RabbitMqHelperSingleton.java Source code

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Here is the source code for sonata.kernel.WimAdaptor.messaging.RabbitMqHelperSingleton.java

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/*
 * Copyright (c) 2015 SONATA-NFV, UCL, NOKIA, THALES, NCSR Demokritos 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.
 * 
 * Neither the name of the SONATA-NFV, UCL, NOKIA, NCSR Demokritos nor the names of its contributors
 * may be used to endorse or promote products derived from this software without specific prior
 * written permission.
 * 
 * This work has been performed in the framework of the SONATA project, funded by the European
 * Commission under Grant number 671517 through the Horizon 2020 and 5G-PPP programmes. The authors
 * would like to acknowledge the contributions of their colleagues of the SONATA partner consortium
 * (www.sonata-nfv.eu).
 *
 * @author Dario Valocchi (Ph.D.), UCL
 * 
 */
package sonata.kernel.WimAdaptor.messaging;

import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;

import org.json.JSONObject;
import org.json.JSONTokener;
import org.slf4j.LoggerFactory;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URISyntaxException;
import java.nio.charset.Charset;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.util.Properties;
import java.util.concurrent.TimeoutException;

public class RabbitMqHelperSingleton {

    private Channel channel;
    private Connection connection;
    private String queueName;
    private String exchangeName;

    private static final String configFilePath = "/etc/son-mano/broker.config";

    private static final org.slf4j.Logger Logger = LoggerFactory.getLogger(RabbitMqHelperSingleton.class);

    private static RabbitMqHelperSingleton myInstance = null;

    private RabbitMqHelperSingleton() {
        Properties brokerConfig = parseConfigFile();
        Logger.info("Connecting to broker...");
        ConnectionFactory cf = new ConnectionFactory();
        if (!brokerConfig.containsKey("broker_url") || !brokerConfig.containsKey("exchange")) {
            Logger.error("Missing broker url configuration.");
            System.exit(1);
        }
        try {

            Logger.info("Connecting to: " + brokerConfig.getProperty("broker_url"));
            cf.setUri(brokerConfig.getProperty("broker_url"));
            connection = cf.newConnection();
            channel = connection.createChannel();
            exchangeName = brokerConfig.getProperty("exchange");
            channel.exchangeDeclare(exchangeName, "topic");
            queueName = exchangeName + "." + "WimAdaptor";
            channel.queueDeclare(queueName, true, false, false, null);
            Logger.info("Binding queue to topics...");

            channel.queueBind(queueName, exchangeName, "platform.management.plugin.register");
            Logger.info("Bound to topic \"platform.platform.management.plugin.register\"");

            channel.queueBind(queueName, exchangeName, "platform.management.plugin.deregister");
            Logger.info("Bound to topic \"platform.platform.management.plugin.deregister\"");

            channel.queueBind(queueName, exchangeName, "infrastructure.#.wan.#");
            Logger.info("[northbound] RabbitMqConsumer - bound to topic \"infrastructure.#.wan.#\"");

        } catch (TimeoutException e) {
            Logger.error(e.getMessage(), e);
        } catch (KeyManagementException e) {
            Logger.error(e.getMessage(), e);
        } catch (NoSuchAlgorithmException e) {
            Logger.error(e.getMessage(), e);
        } catch (URISyntaxException e) {
            Logger.error(e.getMessage(), e);
        } catch (IOException e) {
            Logger.error(e.getMessage(), e);
        }

    }

    public static RabbitMqHelperSingleton getInstance() {
        if (myInstance == null) {
            myInstance = new RabbitMqHelperSingleton();
        }
        return myInstance;
    }

    public Channel getChannel() {
        return this.channel;
    }

    /**
     * Utility function to parse the broker configuration file.
     *
     * @return a Java Properties object representing the json config as a Key-Value map
     */
    private Properties parseConfigFile() {
        Properties prop = new Properties();
        try {
            InputStreamReader in = new InputStreamReader(new FileInputStream(configFilePath),
                    Charset.forName("UTF-8"));

            JSONTokener tokener = new JSONTokener(in);

            JSONObject jsonObject = (JSONObject) tokener.nextValue();

            String brokerUrl = jsonObject.getString("broker_url");
            String exchange = jsonObject.getString("exchange");
            prop.put("broker_url", brokerUrl);
            prop.put("exchange", exchange);
        } catch (FileNotFoundException e) {
            Logger.error("Unable to load Broker Config file", e);
            System.exit(1);
        }

        return prop;
    }

    public String getExchangeName() {
        return exchangeName;
    }

    public String getQueueName() {
        return queueName;
    }

}