gobblin.writer.HiveWritableHdfsDataWriter Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of gobblin-core Show documentation
Gobblin Ingestion Framework
There is a newer version: 0.8.0
/*
 * Copyright (C) 2014-2016 LinkedIn Corp. 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.
 */

package gobblin.writer;

import java.io.IOException;
import java.util.concurrent.atomic.AtomicLong;

import org.apache.hadoop.hive.ql.exec.FileSinkOperator.RecordWriter;
import org.apache.hadoop.hive.ql.io.HiveOutputFormat;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapred.JobConf;

import com.google.common.base.Preconditions;

import gobblin.configuration.State;


/**
 * An extension to {@link FsDataWriter} that writes {@link Writable} records using an
 * {@link org.apache.hadoop.mapred.OutputFormat} that implements {@link HiveOutputFormat}.
 *
 * The records are written using a {@link RecordWriter} created by
 * {@link HiveOutputFormat#getHiveRecordWriter(JobConf, org.apache.hadoop.fs.Path, Class, boolean,
 * java.util.Properties, org.apache.hadoop.util.Progressable)}.
 *
 * @author ziliu
 */
public class HiveWritableHdfsDataWriter extends FsDataWriter {

  protected final RecordWriter writer;
  protected final AtomicLong count = new AtomicLong(0);

  public HiveWritableHdfsDataWriter(HiveWritableHdfsDataWriterBuilder builder, State properties) throws IOException {
    super(builder, properties);

    Preconditions.checkArgument(this.properties.contains(HiveWritableHdfsDataWriterBuilder.WRITER_OUTPUT_FORMAT_CLASS));
    this.writer = getWriter();
  }

  private RecordWriter getWriter() throws IOException {
    try {
      HiveOutputFormat outputFormat = HiveOutputFormat.class
          .cast(Class.forName(this.properties.getProp(HiveWritableHdfsDataWriterBuilder.WRITER_OUTPUT_FORMAT_CLASS))
              .newInstance());

      @SuppressWarnings("unchecked")
      Class writableClass = (Class) Class
          .forName(this.properties.getProp(HiveWritableHdfsDataWriterBuilder.WRITER_WRITABLE_CLASS));

      return outputFormat.getHiveRecordWriter(new JobConf(), this.stagingFile, writableClass, true,
          this.properties.getProperties(), null);
    } catch (Throwable t) {
      throw new IOException(String.format("Failed to create writer"), t);
    }
  }

  @Override
  public void write(Writable record) throws IOException {
    Preconditions.checkNotNull(record);

    this.writer.write(record);
    this.count.incrementAndGet();
  }

  @Override
  public long recordsWritten() {
    return this.count.get();
  }

  @Override
  public long bytesWritten() throws IOException {
    if (!this.fs.exists(this.outputFile)) {
      return 0;
    }

    return this.fs.getFileStatus(this.outputFile).getLen();
  }

  @Override
  public void close() throws IOException {
    this.writer.close(false);
    super.close();
  }

}