com.github.libgraviton.workerbase.WorkerConsumer Maven / Gradle / Ivy

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/**
 * queue consumer - here we have the main logic
 */

package com.github.libgraviton.workerbase;

import com.fasterxml.jackson.jr.ob.JSON;
import com.github.libgraviton.workerbase.model.QueueEvent;
import com.rabbitmq.client.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;

/**
 * WorkerConsumer class.
 *
 * @author List of contributors {@literal }
 * @see http://swisscom.ch
 * @version $Id: $Id
 */
public class WorkerConsumer extends DefaultConsumer {

    private static final Logger LOG = LoggerFactory.getLogger(WorkerConsumer.class);

    private WorkerAbstract worker;

    private String queueName;

    /**
     * constructor
     *
     * @param channel channel
     * @param worker worker
     * @param queueName queueName
     */
    public WorkerConsumer(Channel channel, WorkerAbstract worker, String queueName) {
        super(channel);                
        this.worker = worker;
        this.queueName = queueName;
    }

    /**
     * {@inheritDoc}
     *
     * handles a delivery
     */
    @Override
    public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body)
            throws IOException {
        String message = new String(body, "UTF-8");
        LOG.info("Received '" + envelope.getDeliveryTag() + "':'" + message + "'");

        // deserialize
        QueueEvent queueEvent = JSON.std.beanFrom(QueueEvent.class, message);
        
        // give to worker
        worker.handleDelivery(queueEvent, envelope.getDeliveryTag(), getChannel());
    }

    @Override
    public void handleConsumeOk(String consumerTag) {
        LOG.info("Connection to message queue '" + queueName +"' established.");
        LOG.info("Waiting for messages...");
    }

    @Override
    public void handleShutdownSignal(String consumerTag, ShutdownSignalException sig) {
        LOG.info("Lost connection to message queue '" + queueName + "'.");
        if(sig.getReference() instanceof Channel) {
            Channel channel = (Channel) sig.getReference();
            Connection connection = channel.getConnection();

            LOG.info("Channel is closed. Creating new channel for connection '" + connection + "'.");
            try {
                worker.getQueueManager().createChannel(connection);
            } catch (IOException e) {
                LOG.error("Cannot create channel for connection '" + connection + "'.", e);
            }
        }
    }
}