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/*
 * 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.CodecFactory.DEFAULT_DEFLATE_LEVEL;
import static org.apache.avro.file.CodecFactory.DEFAULT_XZ_LEVEL;

/**
 * An {@link org.apache.hadoop.mapred.OutputFormat} for Avro data files.
 * 

* 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 extends FileOutputFormat, 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 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 void configureDataFileWriter(DataFileWriter 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 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: *

    *
  • If mapred.output.compress is true then look for codec otherwise no * compression
  • *
  • Use avro.output.codec if populated
  • *
  • Next use mapred.output.compression.codec if populated
  • *
  • If not default to Deflate Codec
  • *
*/ 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); 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 { factory = CodecFactory.fromString(codecName); } } } return factory; } @Override public RecordWriter, 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 writer = new DataFileWriter(dataModel.createDatumWriter(null)); configureDataFileWriter(writer, job); Path path = FileOutputFormat.getTaskOutputPath(job, name + EXT); writer.create(schema, path.getFileSystem(job).create(path)); return new RecordWriter, NullWritable>() { @Override public void write(AvroWrapper wrapper, NullWritable ignore) throws IOException { writer.append(wrapper.datum()); } @Override public void close(Reporter reporter) throws IOException { writer.close(); } }; } }




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