/**
* 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.crunch.types.avro;
import java.io.IOException;
import org.apache.avro.Schema;
import org.apache.avro.file.CodecFactory;
import org.apache.avro.file.DataFileWriter;
import org.apache.avro.mapred.AvroJob;
import org.apache.avro.mapred.AvroWrapper;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
/** An {@link org.apache.hadoop.mapreduce.OutputFormat} for Avro data files. */
public class AvroOutputFormat<T> extends FileOutputFormat<AvroWrapper<T>, NullWritable> {
public static <S> DataFileWriter<S> getDataFileWriter(Path path, Configuration conf) throws IOException {
Schema schema = null;
String outputName = conf.get("crunch.namedoutput");
if (outputName != null && !outputName.isEmpty()) {
schema = (new Schema.Parser()).parse(conf.get("avro.output.schema." + outputName));
} else {
schema = AvroJob.getOutputSchema(conf);
}
DataFileWriter<S> writer = new DataFileWriter<S>(AvroMode.fromConfiguration(conf).<S>getWriter(schema));
JobConf jc = new JobConf(conf);
/* copied from org.apache.avro.mapred.AvroOutputFormat */
if (org.apache.hadoop.mapred.FileOutputFormat.getCompressOutput(jc)) {
int level = conf.getInt(org.apache.avro.mapred.AvroOutputFormat.DEFLATE_LEVEL_KEY,
org.apache.avro.mapred.AvroOutputFormat.DEFAULT_DEFLATE_LEVEL);
String codecName = conf.get(AvroJob.OUTPUT_CODEC,
org.apache.avro.file.DataFileConstants.DEFLATE_CODEC);
CodecFactory codec = codecName.equals(org.apache.avro.file.DataFileConstants.DEFLATE_CODEC)
? CodecFactory.deflateCodec(level)
: CodecFactory.fromString(codecName);
writer.setCodec(codec);
}
writer.setSyncInterval(jc.getInt(org.apache.avro.mapred.AvroOutputFormat.SYNC_INTERVAL_KEY,
org.apache.avro.file.DataFileConstants.DEFAULT_SYNC_INTERVAL));
FileSystem fs = path.getFileSystem(conf);
if (fs.exists(path)) {
writer.create(schema, fs.append(path));
} else {
writer.create(schema, fs.create(path));
}
return writer;
}
@Override
public RecordWriter<AvroWrapper<T>, NullWritable> getRecordWriter(TaskAttemptContext context) throws IOException,
InterruptedException {
Configuration conf = context.getConfiguration();
Path path = getDefaultWorkFile(context, org.apache.avro.mapred.AvroOutputFormat.EXT);
final DataFileWriter<T> writer = getDataFileWriter(path, conf);
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(TaskAttemptContext context) throws IOException, InterruptedException {
writer.close();
}
};
}
}