content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 org.apache.apex.malhar.contrib.rabbitmq;
  
  import java.io.IOException;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.apache.apex.malhar.lib.wal.WindowDataManager;
  
  import com.rabbitmq.client.Channel;
  import com.rabbitmq.client.Connection;
  import com.rabbitmq.client.ConnectionFactory;
  import com.rabbitmq.client.QueueingConsumer;
  
  import com.datatorrent.api.Context.OperatorContext;
  import com.datatorrent.common.util.BaseOperator;
  import com.datatorrent.netlet.util.DTThrowable;
  
  /**
   * This is the base implementation of a RabbitMQ output operator.&nbsp;
   * A concrete operator should be created from this skeleton implementation.
   * <p>
   * <br>
   * Ports:<br>
   * <b>Input</b>: Can have any number of input ports<br>
   * <b>Output</b>: no output port<br>
   * <br>
   * Properties:<br>
   * <b>host</b>:the address for the consumer to connect <br>
   * <br>
   * Compile time checks:<br>
   * None<br>
   * <br>
   * Run time checks:<br>
   * None<br>
   * <br>
   * <b>Benchmarks</b>: Blast as many tuples as possible in inline mode<br>
   * <table border="1" cellspacing=1 cellpadding=1 summary="Benchmark table for AbstractRabbitMQOutputOperator&lt;K,V extends Number&gt; operator template">
   * <tr><th>In-Bound</th><th>Out-bound</th><th>Comments</th></tr>
   * <tr><td>One tuple per key per window per port</td><td><b>10 thousand K,V pairs/s</td><td>Out-bound rate is the main determinant of performance. Operator can process about 10 thousand unique (k,v immutable pairs) tuples/sec as RabbitMQ DAG. Tuples are assumed to be
   * immutable. If you use mutable tuples and have lots of keys, the benchmarks may differ</td></tr>
   * </table><br>
   * <br>
   * </p>
   * @displayName Abstract RabbitMQ Output
   * @category Messaging
   * @tags output operator
   *
   * @since 0.3.2
   */
  public class AbstractRabbitMQOutputOperator extends BaseOperator
  {
    private static final Logger logger = LoggerFactory.getLogger(AbstractRabbitMQOutputOperator.class);
    transient ConnectionFactory connFactory = new ConnectionFactory();
    transient QueueingConsumer consumer = null;
    transient Connection connection = null;
    transient Channel channel = null;
    transient String exchange = "testEx";
    transient String queueName = "testQ";
  
    private WindowDataManager windowDataManager;
    private transient long currentWindowId;
    private transient long largestRecoveryWindowId;
    private transient int operatorContextId;
    protected transient boolean skipProcessingTuple = false;
    private transient OperatorContext context;
  
  
    @Override
    public void setup(OperatorContext context)
    {
      // Needed to setup idempotency storage manager in setter
      this.context = context;
      this.operatorContextId = context.getId();
  
      try {
        connFactory.setHost("localhost");
        connection = connFactory.newConnection();
        channel = connection.createChannel();
        channel.exchangeDeclare(exchange, "fanout");
  
        this.windowDataManager.setup(context);
  
      } catch (IOException ex) {
        logger.debug(ex.toString());
        DTThrowable.rethrow(ex);
      }
    }
  
    @Override
    public void beginWindow(long windowId)
    {
      currentWindowId = windowId;
      largestRecoveryWindowId = windowDataManager.getLargestCompletedWindow();
      if (windowId <= largestRecoveryWindowId) {
        // Do not resend already sent tuples
        skipProcessingTuple = true;
      } else {
        skipProcessingTuple = false;
      }
    }
  
    /**
     * {@inheritDoc}
     */
    @Override
    public void endWindow()
    {
      if (currentWindowId < largestRecoveryWindowId) {
        // ignore
        return;
      }
      try {
        windowDataManager.save("processedWindow", currentWindowId);
      } catch (IOException e) {
        DTThrowable.rethrow(e);
      }
    }
  
    public void setQueueName(String queueName)
    {
      this.queueName = queueName;
    }
  
    public void setExchange(String exchange)
    {
      this.exchange = exchange;
    }
  
    @Override
    public void teardown()
    {
      try {
        channel.close();
        connection.close();
        this.windowDataManager.teardown();
      } catch (IOException ex) {
        logger.debug(ex.toString());
      }
    }
  
    public WindowDataManager getWindowDataManager()
    {
      return windowDataManager;
    }
  
    public void setWindowDataManager(WindowDataManager windowDataManager)
    {
      this.windowDataManager = windowDataManager;
    }
  
  }
  