/*
* 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.kylin.engine.mr.steps;
import java.io.IOException;
import java.util.List;
import org.apache.commons.cli.Options;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.BytesWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.LazyOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.MultipleOutputs;
import org.apache.hadoop.mapreduce.lib.output.SequenceFileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.ToolRunner;
import org.apache.kylin.common.KylinConfig;
import org.apache.kylin.cube.CubeInstance;
import org.apache.kylin.cube.CubeManager;
import org.apache.kylin.cube.CubeSegment;
import org.apache.kylin.engine.mr.IMRInput.IMRTableInputFormat;
import org.apache.kylin.engine.mr.MRUtil;
import org.apache.kylin.engine.mr.common.AbstractHadoopJob;
import org.apache.kylin.engine.mr.common.BatchConstants;
import org.apache.kylin.metadata.model.TblColRef;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*/
public class FactDistinctColumnsJob extends AbstractHadoopJob {
protected static final Logger logger = LoggerFactory.getLogger(FactDistinctColumnsJob.class);
@Override
public int run(String[] args) throws Exception {
Options options = new Options();
try {
options.addOption(OPTION_JOB_NAME);
options.addOption(OPTION_CUBE_NAME);
options.addOption(OPTION_CUBING_JOB_ID);
options.addOption(OPTION_OUTPUT_PATH);
options.addOption(OPTION_SEGMENT_ID);
options.addOption(OPTION_STATISTICS_ENABLED);
options.addOption(OPTION_STATISTICS_OUTPUT);
options.addOption(OPTION_STATISTICS_SAMPLING_PERCENT);
parseOptions(options, args);
job = Job.getInstance(getConf(), getOptionValue(OPTION_JOB_NAME));
String job_id = getOptionValue(OPTION_CUBING_JOB_ID);
job.getConfiguration().set(BatchConstants.ARG_CUBING_JOB_ID, job_id);
String cubeName = getOptionValue(OPTION_CUBE_NAME);
Path output = new Path(getOptionValue(OPTION_OUTPUT_PATH));
String segmentID = getOptionValue(OPTION_SEGMENT_ID);
String statistics_enabled = getOptionValue(OPTION_STATISTICS_ENABLED);
String statistics_output = getOptionValue(OPTION_STATISTICS_OUTPUT);
String statistics_sampling_percent = getOptionValue(OPTION_STATISTICS_SAMPLING_PERCENT);
// ----------------------------------------------------------------------------
// add metadata to distributed cache
CubeManager cubeMgr = CubeManager.getInstance(KylinConfig.getInstanceFromEnv());
CubeInstance cube = cubeMgr.getCube(cubeName);
List<TblColRef> columnsNeedDict = cubeMgr.getAllDictColumnsOnFact(cube.getDescriptor());
int reducerCount = columnsNeedDict.size();
int uhcReducerCount = cube.getConfig().getUHCReducerCount();
int[] uhcIndex = cubeMgr.getUHCIndex(cube.getDescriptor());
for (int index : uhcIndex) {
if (index == 1) {
reducerCount += uhcReducerCount - 1;
}
}
if (reducerCount > 255) {
throw new IllegalArgumentException("The max reducer number for FactDistinctColumnsJob is 255, but now it is " + reducerCount + ", decrease 'kylin.engine.mr.uhc-reducer-count'");
}
job.getConfiguration().set(BatchConstants.CFG_CUBE_NAME, cubeName);
job.getConfiguration().set(BatchConstants.CFG_CUBE_SEGMENT_ID, segmentID);
job.getConfiguration().set(BatchConstants.CFG_STATISTICS_ENABLED, statistics_enabled);
job.getConfiguration().set(BatchConstants.CFG_STATISTICS_OUTPUT, statistics_output);
job.getConfiguration().set(BatchConstants.CFG_STATISTICS_SAMPLING_PERCENT, statistics_sampling_percent);
logger.info("Starting: " + job.getJobName());
setJobClasspath(job, cube.getConfig());
CubeSegment segment = cube.getSegmentById(segmentID);
if (segment == null) {
logger.error("Failed to find {} in cube {}", segmentID, cube);
for (CubeSegment s : cube.getSegments()) {
logger.error(s.getName() + " with status " + s.getStatus());
}
throw new IllegalStateException();
}
setupMapper(segment);
setupReducer(output, "true".equalsIgnoreCase(statistics_enabled) ? reducerCount + 2 : reducerCount);
attachCubeMetadata(cube, job.getConfiguration());
/**
* don't compress the reducer output so that {@link CreateDictionaryJob} and {@link UpdateCubeInfoAfterBuildStep}
* could read the reducer file directly
*/
job.getConfiguration().set(BatchConstants.CFG_MAPRED_OUTPUT_COMPRESS, "false");
return waitForCompletion(job);
} finally {
if (job != null)
cleanupTempConfFile(job.getConfiguration());
}
}
private void setupMapper(CubeSegment cubeSeg) throws IOException {
IMRTableInputFormat flatTableInputFormat = MRUtil.getBatchCubingInputSide(cubeSeg).getFlatTableInputFormat();
flatTableInputFormat.configureJob(job);
job.setMapperClass(FactDistinctColumnsMapper.class);
job.setCombinerClass(FactDistinctColumnsCombiner.class);
job.setMapOutputKeyClass(SelfDefineSortableKey.class);
job.setMapOutputValueClass(Text.class);
}
private void setupReducer(Path output, int numberOfReducers) throws IOException {
job.setReducerClass(FactDistinctColumnsReducer.class);
job.setPartitionerClass(FactDistinctColumnPartitioner.class);
job.setNumReduceTasks(numberOfReducers);
//make each reducer output to respective dir
MultipleOutputs.addNamedOutput(job, BatchConstants.CFG_OUTPUT_COLUMN, SequenceFileOutputFormat.class, NullWritable.class, Text.class);
MultipleOutputs.addNamedOutput(job, BatchConstants.CFG_OUTPUT_DICT, SequenceFileOutputFormat.class, NullWritable.class, BytesWritable.class);
MultipleOutputs.addNamedOutput(job, BatchConstants.CFG_OUTPUT_STATISTICS, SequenceFileOutputFormat.class, LongWritable.class, BytesWritable.class);
MultipleOutputs.addNamedOutput(job, BatchConstants.CFG_OUTPUT_PARTITION, TextOutputFormat.class, NullWritable.class, LongWritable.class);
FileOutputFormat.setOutputPath(job, output);
job.getConfiguration().set(BatchConstants.CFG_OUTPUT_PATH, output.toString());
//prevent to create zero-sized default output
LazyOutputFormat.setOutputFormatClass(job, SequenceFileOutputFormat.class);
deletePath(job.getConfiguration(), output);
}
public static void main(String[] args) throws Exception {
FactDistinctColumnsJob job = new FactDistinctColumnsJob();
int exitCode = ToolRunner.run(job, args);
System.exit(exitCode);
}
}