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;
  
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.util.Map;
  import java.net.URLDecoder;
  import java.nio.charset.StandardCharsets;
  
  import org.apache.hadoop.io.NullWritable;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.mapred.JobConf;
  import org.apache.hadoop.mapred.Reporter;
  import org.apache.hadoop.mapred.FileOutputFormat;
  import org.apache.hadoop.mapred.RecordWriter;
  import org.apache.hadoop.util.Progressable;
  
  import org.apache.avro.Schema;
  import org.apache.avro.file.DataFileWriter;
  import org.apache.avro.file.CodecFactory;
  import org.apache.avro.generic.GenericData;
  import org.apache.avro.hadoop.file.HadoopCodecFactory;
  
  import static org.apache.avro.file.DataFileConstants.DEFAULT_SYNC_INTERVAL;
  import static org.apache.avro.file.DataFileConstants.DEFLATE_CODEC;
  import static org.apache.avro.file.DataFileConstants.XZ_CODEC;
  import static org.apache.avro.file.DataFileConstants.ZSTANDARD_CODEC;
  import static org.apache.avro.file.CodecFactory.DEFAULT_DEFLATE_LEVEL;
  import static org.apache.avro.file.CodecFactory.DEFAULT_XZ_LEVEL;
  import static org.apache.avro.file.CodecFactory.DEFAULT_ZSTANDARD_LEVEL;
  import static org.apache.avro.file.CodecFactory.DEFAULT_ZSTANDARD_BUFFERPOOL;
  
  /**
   * An {@link org.apache.hadoop.mapred.OutputFormat} for Avro data files.
   * <p/>
   * You can specify various options using Job Configuration properties. Look at
   * the fields in {@link AvroJob} as well as this class to get an overview of the
   * supported options.
   */
  public class AvroOutputFormat<T> extends FileOutputFormat<AvroWrapper<T>, NullWritable> {
  
    /** The file name extension for avro data files. */
    public final static String EXT = ".avro";
  
    /** The configuration key for Avro deflate level. */
    public static final String DEFLATE_LEVEL_KEY = "avro.mapred.deflate.level";
  
    /** The configuration key for Avro XZ level. */
    public static final String XZ_LEVEL_KEY = "avro.mapred.xz.level";
  
    /** The configuration key for Avro ZSTD level. */
    public static final String ZSTD_LEVEL_KEY = "avro.mapred.zstd.level";
  
    /** The configuration key for Avro ZSTD buffer pool. */
    public static final String ZSTD_BUFFERPOOL_KEY = "avro.mapred.zstd.bufferpool";
  
    /** The configuration key for Avro sync interval. */
    public static final String SYNC_INTERVAL_KEY = "avro.mapred.sync.interval";
  
    /** Enable output compression using the deflate codec and specify its level. */
    public static void setDeflateLevel(JobConf job, int level) {
      FileOutputFormat.setCompressOutput(job, true);
      job.setInt(DEFLATE_LEVEL_KEY, level);
    }
  
    /**
     * Set the sync interval to be used by the underlying {@link DataFileWriter}.
     */
    public static void setSyncInterval(JobConf job, int syncIntervalInBytes) {
      job.setInt(SYNC_INTERVAL_KEY, syncIntervalInBytes);
    }
  
    static <T> void configureDataFileWriter(DataFileWriter<T> writer, JobConf job) throws UnsupportedEncodingException {
  
      CodecFactory factory = getCodecFactory(job);
  
      if (factory != null) {
        writer.setCodec(factory);
      }
  
      writer.setSyncInterval(job.getInt(SYNC_INTERVAL_KEY, DEFAULT_SYNC_INTERVAL));
  
      // copy metadata from job
      for (Map.Entry<String, String> e : job) {
        if (e.getKey().startsWith(AvroJob.TEXT_PREFIX))
          writer.setMeta(e.getKey().substring(AvroJob.TEXT_PREFIX.length()), e.getValue());
        if (e.getKey().startsWith(AvroJob.BINARY_PREFIX))
          writer.setMeta(e.getKey().substring(AvroJob.BINARY_PREFIX.length()),
              URLDecoder.decode(e.getValue(), StandardCharsets.ISO_8859_1.name()).getBytes(StandardCharsets.ISO_8859_1));
      }
    }
  
    /**
     * This will select the correct compression codec from the JobConf. The order of
     * selection is as follows:
     * <ul>
     * <li>If mapred.output.compress is true then look for codec otherwise no
     * compression</li>
     * <li>Use avro.output.codec if populated</li>
     * <li>Next use mapred.output.compression.codec if populated</li>
     * <li>If not default to Deflate Codec</li>
     * </ul>
     */
    static CodecFactory getCodecFactory(JobConf job) {
      CodecFactory factory = null;
  
      if (FileOutputFormat.getCompressOutput(job)) {
        int deflateLevel = job.getInt(DEFLATE_LEVEL_KEY, DEFAULT_DEFLATE_LEVEL);
        int xzLevel = job.getInt(XZ_LEVEL_KEY, DEFAULT_XZ_LEVEL);
        int zstdLevel = job.getInt(ZSTD_LEVEL_KEY, DEFAULT_ZSTANDARD_LEVEL);
        boolean zstdBufferPool = job.getBoolean(ZSTD_BUFFERPOOL_KEY, DEFAULT_ZSTANDARD_BUFFERPOOL);
        String codecName = job.get(AvroJob.OUTPUT_CODEC);
  
        if (codecName == null) {
          String codecClassName = job.get("mapred.output.compression.codec", null);
          String avroCodecName = HadoopCodecFactory.getAvroCodecName(codecClassName);
          if (codecClassName != null && avroCodecName != null) {
            factory = HadoopCodecFactory.fromHadoopString(codecClassName);
            job.set(AvroJob.OUTPUT_CODEC, avroCodecName);
            return factory;
          } else {
            return CodecFactory.deflateCodec(deflateLevel);
          }
        } else {
          if (codecName.equals(DEFLATE_CODEC)) {
            factory = CodecFactory.deflateCodec(deflateLevel);
          } else if (codecName.equals(XZ_CODEC)) {
            factory = CodecFactory.xzCodec(xzLevel);
          } else if (codecName.equals(ZSTANDARD_CODEC)) {
            factory = CodecFactory.zstandardCodec(zstdLevel, false, zstdBufferPool);
          } else {
            factory = CodecFactory.fromString(codecName);
          }
        }
      }
  
      return factory;
    }
  
    @Override
    public RecordWriter<AvroWrapper<T>, NullWritable> getRecordWriter(FileSystem ignore, JobConf job, String name,
        Progressable prog) throws IOException {
  
      boolean isMapOnly = job.getNumReduceTasks() == 0;
      Schema schema = isMapOnly ? AvroJob.getMapOutputSchema(job) : AvroJob.getOutputSchema(job);
      GenericData dataModel = AvroJob.createDataModel(job);
  
      final DataFileWriter<T> writer = new DataFileWriter<T>(dataModel.createDatumWriter(null));
  
      configureDataFileWriter(writer, job);
  
      Path path = FileOutputFormat.getTaskOutputPath(job, name + EXT);
      writer.create(schema, path.getFileSystem(job).create(path));
  
      return new RecordWriter<AvroWrapper<T>, NullWritable>() {
        @Override
        public void write(AvroWrapper<T> wrapper, NullWritable ignore) throws IOException {
          writer.append(wrapper.datum());
        }
  
        @Override
        public void close(Reporter reporter) throws IOException {
          writer.close();
        }
      };
    }
  
  }
  