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
   *
   *     https://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.avro.mapred.tether;
  
  import java.io.IOException;
  
  import org.apache.hadoop.io.NullWritable;
  import org.apache.hadoop.mapred.JobConf;
  import org.apache.hadoop.mapred.MapRunner;
  import org.apache.hadoop.mapred.OutputCollector;
  import org.apache.hadoop.mapred.RecordReader;
  import org.apache.hadoop.mapred.Reporter;
  import org.apache.hadoop.mapred.Counters.Counter;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.apache.avro.mapred.AvroJob;
  
  class TetherMapRunner extends MapRunner<TetherData, NullWritable, TetherData, NullWritable> {
  
    private static final Logger LOG = LoggerFactory.getLogger(TetherMapRunner.class);
  
    private JobConf job;
    private TetheredProcess process;
  
    public void configure(JobConf job) {
      this.job = job;
    }
  
    @SuppressWarnings("unchecked")
    public void run(RecordReader<TetherData, NullWritable> recordReader,
        OutputCollector<TetherData, NullWritable> collector, Reporter reporter) throws IOException {
      try {
        // start tethered process
        process = new TetheredProcess(job, collector, reporter);
  
        // configure it
        LOG.info("send configure to subprocess for map task");
        process.inputClient.configure(TaskType.MAP, job.get(AvroJob.INPUT_SCHEMA),
            AvroJob.getMapOutputSchema(job).toString());
  
        LOG.info("send partitions to subprocess for map task");
        process.inputClient.partitions(job.getNumReduceTasks());
  
        // run map
        Counter inputRecordCounter = reporter.getCounter("org.apache.hadoop.mapred.Task$Counter", "MAP_INPUT_RECORDS");
        TetherData data = new TetherData();
        while (recordReader.next(data, NullWritable.get())) {
          process.inputClient.input(data.buffer(), data.count());
          inputRecordCounter.increment(data.count() - 1);
          if (process.outputService.isFinished())
            break;
        }
        LOG.info("send complete to subprocess for map task");
        process.inputClient.complete();
  
        // wait for completion
        if (process.outputService.waitForFinish())
          throw new IOException("Task failed: " + process.outputService.error());
  
      } catch (Throwable t) { // send abort
        LOG.warn("Task failed", t);
        process.inputClient.abort();
        throw new IOException("Task failed: " + t, t);
  
      } finally { // clean up
        if (process != null)
          process.close();
      }
    }
  
  }
  