Reputation: 363
I have a Map Reduce job that uses OOZIE workflow xml and writes output in sequence file format(org.apache.hadoop.mapreduce.lib.output.SequenceFileOutputFormat), is there something like this for saving in Parquet format also ?, I could not find any under https://hadoop.apache.org/docs/stable/api/org/apache/hadoop/mapreduce/lib/output/package-summary.html
or should I be using a different approach ?
Please advise .
Thanks
Mapper:
import org.apache.avro.Schema;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import java.io.IOException;
import java.util.StringTokenizer;
public class TestMapper1 extends Mapper<LongWritable, Text, Text, IntWritable>{
@Override
public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
StringTokenizer str = new StringTokenizer(value.toString());
while (str.hasMoreTokens()) {
String word = str.nextToken();
context.write(new Text(word), new IntWritable(1));
}
}
}
Reducer:
import org.apache.avro.Schema;
import org.apache.avro.generic.GenericData;
import org.apache.avro.generic.GenericRecord;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;
import java.io.IOException;
public class TestReducer1 extends Reducer<Text, IntWritable, Void, GenericRecord> {
private static final Schema MAPPING_SCHEMA = new Schema.Parser().parse(
"{\n" +
" \"type\": \"record\",\n" +
" \"name\": \"TextFile\",\n" +
" \"doc\": \"Text File\",\n" +
" \"fields\":\n" +
" [\n" +
" {\"name\": \"col1\", \"type\": \"string\"}\n"+
" ]\n"+
"}\n");
@Override
public void reduce(Text key, Iterable<IntWritable> values, Context context)
throws IOException, InterruptedException {
GenericRecord record = new GenericData.Record(MAPPING_SCHEMA);
int sum = 0;
for (IntWritable i : values) {
sum += i.get();
}
record.put("col1",String.valueOf(sum));
context.write(null, record);
}
}
Driver:
import org.apache.avro.Schema;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.parquet.avro.AvroParquetOutputFormat;
public class Driver1 {
public static void main(String[] args) throws Exception {
Schema MAPPING_SCHEMA = new Schema.Parser().parse(
"{\n" +
" \"type\": \"record\",\n" +
" \"name\": \"TextFile\",\n" +
" \"doc\": \"Text File\",\n" +
" \"fields\":\n" +
" [\n" +
" {\"name\": \"col1\", \"type\": \"string\"}\n"+
" ]\n"+
"}\n");
if (args.length != 2) {
System.err.println("Usage: WordCount <InPath> <OutPath>");
System.exit(2);
}
Configuration conf = new Configuration();
//
Job job = Job.getInstance(conf, "ParquetConvert WordCount");
job.setJarByClass(TestMapper1.class);
job.setMapperClass(TestMapper1.class);
job.setReducerClass(TestReducer1.class);
job.setNumReduceTasks(1);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(IntWritable.class);
job.setOutputFormatClass(AvroParquetOutputFormat.class);
// setting schema
AvroParquetOutputFormat.setSchema(job, MAPPING_SCHEMA);
FileInputFormat.addInputPath(job, new Path(args[0]));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
System.exit(job.waitForCompletion(true) ? 0 : 1);
}
}
Upvotes: 0
Views: 93
Reputation: 191743
Oozie shouldn't control what libraries get included in your MapReduce job(s).
ParquetOutputFormat
is not built into Hadoop.
You can find it here.
Maven target
<dependency>
<groupId>org.apache.parquet</groupId>
<artifactId>parquet-hadoop</artifactId>
<version>${parquet.version}</version>
</dependency>
Upvotes: 0