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.examples.kafka.hdfs2kafka;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.List;
  
  import javax.validation.ConstraintViolationException;
  
  import org.junit.Assert;
  import org.junit.Rule;
  import org.junit.Test;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.apache.commons.io.FileUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.net.NetUtils;
  
  import com.datatorrent.api.LocalMode;
  
  import info.batey.kafka.unit.KafkaUnit;
  import info.batey.kafka.unit.KafkaUnitRule;
  
  import static org.junit.Assert.assertTrue;
  
  /**
   * Test the DAG declaration in local mode.
   */
  public class ApplicationTest
  {
    private static final Logger LOG = LoggerFactory.getLogger(ApplicationTest.class);
    private static final String TOPIC = "hdfs2kafka";
    private static final String directory = "target/hdfs2kafka";
    private static final String FILE_NAME = "messages.txt";
  
    private static final int zkPort = NetUtils.getFreeSocketPort();
    private static final int brokerPort = NetUtils.getFreeSocketPort();
    private static final String BROKER = "localhost:" + brokerPort;
    //private static final String FILE_PATH = FILE_DIR + "/" + FILE_NAME + ".0";     // first part
  
    // test messages
    private static String[] lines = {
      "1st line",
      "2nd line",
      "3rd line",
      "4th line",
      "5th line",
    };
  
    // broker port must match properties.xml
    @Rule
    public KafkaUnitRule kafkaUnitRule = new KafkaUnitRule(zkPort, brokerPort);
  
    @Test
    public void testApplication() throws IOException, Exception
    {
      try {
        // create file in monitored HDFS directory
        createFile();
  
        // run app asynchronously; terminate after results are checked
        LocalMode.Controller lc = asyncRun();
  
        // get messages from Kafka topic and compare with input
        chkOutput();
  
        lc.shutdown();
      } catch (ConstraintViolationException e) {
        Assert.fail("constraint violations: " + e.getConstraintViolations());
      }
    }
  
    // create a file with content from 'lines'
    private void createFile() throws IOException
    {
      // remove old file and create new one
      File file = new File(directory, FILE_NAME);
      FileUtils.deleteQuietly(file);
      try {
        String data = StringUtils.join(lines, "\n") + "\n";    // add final newline
        FileUtils.writeStringToFile(file, data, "UTF-8");
      } catch (IOException e) {
        LOG.error("Error: Failed to create file {} in {}", FILE_NAME, directory);
        e.printStackTrace();
      }
      LOG.debug("Created file {} with {} lines in {}", FILE_NAME, lines.length, directory);
    }
  
    private LocalMode.Controller asyncRun() throws Exception
    {
      Configuration conf = getConfig();
      LocalMode lma = LocalMode.newInstance();
      lma.prepareDAG(new Application(), conf);
      LocalMode.Controller lc = lma.getController();
      lc.runAsync();
      return lc;
    }
  
    private Configuration getConfig()
    {
      Configuration conf = new Configuration(false);
      conf.addResource(this.getClass().getResourceAsStream("/META-INF/properties-hdfs2kafka.xml"));
      conf.set("dt.operator.lines.prop.directory", directory);
      conf.set("dt.operator.kafkaOutput.prop.producerProperties",
          "serializer.class=kafka.serializer.StringEncoder,producer.type=async,metadata.broker.list=" + BROKER);
  
      return conf;
    }
  
    private void chkOutput() throws Exception
    {
      KafkaUnit ku = kafkaUnitRule.getKafkaUnit();
      List<String> messages = null;
  
      // wait for messages to appear in kafka
      Thread.sleep(10000);
  
      try {
        messages = ku.readMessages(TOPIC, lines.length);
      } catch (Exception e) {
        LOG.error("Error: Got exception {}", e);
      }
  
      int i = 0;
      for (String msg : messages) {
        assertTrue("Error: message mismatch", msg.equals(lines[i]));
        ++i;
      }
    }
  
  }
  