/**
* 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.hadoop.mapred;
import static org.junit.Assert.assertTrue;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.filecache.DistributedCache;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.lib.IdentityReducer;
import org.junit.Ignore;
import org.junit.Test;
/**
* Class to test mapred debug Script
*/
@Ignore //disabled until we fix the issues in running debug scripts
public class TestMiniMRMapRedDebugScript {
private static final Log LOG =
LogFactory.getLog(TestMiniMRMapRedDebugScript.class.getName());
private MiniMRCluster mr;
private MiniDFSCluster dfs;
private FileSystem fileSys;
/**
* Fail map class
*/
public static class MapClass extends MapReduceBase
implements Mapper<LongWritable, Text, Text, IntWritable> {
public void map (LongWritable key, Text value,
OutputCollector<Text, IntWritable> output,
Reporter reporter) throws IOException {
System.err.println("Bailing out");
throw new IOException();
}
}
/**
* Reads tasklog and returns it as string after trimming it.
* @param filter Task log filter; can be STDOUT, STDERR,
* SYSLOG, DEBUGOUT, DEBUGERR
* @param taskId The task id for which the log has to collected
* @param isCleanup whether the task is a cleanup attempt or not.
* @return task log as string
* @throws IOException
*/
public static String readTaskLog(TaskLog.LogName filter,
TaskAttemptID taskId,
boolean isCleanup)
throws IOException {
// string buffer to store task log
StringBuffer result = new StringBuffer();
int res;
// reads the whole tasklog into inputstream
InputStream taskLogReader = new TaskLog.Reader(taskId, filter, 0, -1, isCleanup);
// construct string log from inputstream.
byte[] b = new byte[65536];
while (true) {
res = taskLogReader.read(b);
if (res > 0) {
result.append(new String(b));
} else {
break;
}
}
taskLogReader.close();
// trim the string and return it
String str = result.toString();
str = str.trim();
return str;
}
/**
* Launches failed map task and debugs the failed task
* @param conf configuration for the mapred job
* @param inDir input path
* @param outDir output path
* @param debugDir debug directory where script is present
* @param debugCommand The command to execute script
* @param input Input text
* @return the output of debug script
* @throws IOException
*/
public String launchFailMapAndDebug(JobConf conf,
Path inDir,
Path outDir,
Path debugDir,
String debugScript,
String input)
throws IOException {
// set up the input file system and write input text.
FileSystem inFs = inDir.getFileSystem(conf);
FileSystem outFs = outDir.getFileSystem(conf);
outFs.delete(outDir, true);
if (!inFs.mkdirs(inDir)) {
throw new IOException("Mkdirs failed to create " + inDir.toString());
}
{
// write input into input file
DataOutputStream file = inFs.create(new Path(inDir, "part-0"));
file.writeBytes(input);
file.close();
}
// configure the mapred Job for failing map task.
conf.setJobName("failmap");
conf.setMapperClass(MapClass.class);
conf.setReducerClass(IdentityReducer.class);
conf.setNumMapTasks(1);
conf.setNumReduceTasks(0);
conf.setMapDebugScript(debugScript);
FileInputFormat.setInputPaths(conf, inDir);
FileOutputFormat.setOutputPath(conf, outDir);
String TEST_ROOT_DIR = new Path(System.getProperty("test.build.data",
"/tmp")).toString().replace(' ', '+');
conf.set("test.build.data", TEST_ROOT_DIR);
// copy debug script to cache from local file system.
FileSystem debugFs = debugDir.getFileSystem(conf);
Path scriptPath = new Path(debugDir,"testscript.txt");
Path cachePath = new Path("/cacheDir");
if (!debugFs.mkdirs(cachePath)) {
throw new IOException("Mkdirs failed to create " + cachePath.toString());
}
debugFs.copyFromLocalFile(scriptPath,cachePath);
URI uri = debugFs.getUri().resolve(cachePath+"/testscript.txt#testscript");
DistributedCache.createSymlink(conf);
DistributedCache.addCacheFile(uri, conf);
RunningJob job =null;
// run the job. It will fail with IOException.
try {
job = new JobClient(conf).submitJob(conf);
} catch (IOException e) {
LOG.info("Running Job failed", e);
}
JobID jobId = job.getID();
// construct the task id of first map task of failmap
TaskAttemptID taskId = new TaskAttemptID(new TaskID(jobId,true, 0), 0);
// wait for the job to finish.
while (!job.isComplete()) ;
// return the output of debugout log.
return readTaskLog(TaskLog.LogName.DEBUGOUT,taskId, false);
}
/**
* Tests Map task's debug script
*
* In this test, we launch a mapreduce program which
* writes 'Bailing out' to stderr and throws an exception.
* We will run the script when tsk fails and validate
* the output of debug out log.
*
*/
@Test
public void testMapDebugScript() throws Exception {
try {
// create configuration, dfs, file system and mapred cluster
Configuration cnf = new Configuration();
dfs = new MiniDFSCluster(cnf, 1, true, null);
fileSys = dfs.getFileSystem();
mr = new MiniMRCluster(2, fileSys.getName(), 1);
JobConf conf = mr.createJobConf();
// intialize input, output and debug directories
final Path debugDir = new Path("build/test/debug");
Path inDir = new Path("testing/wc/input");
Path outDir = new Path("testing/wc/output");
// initialize debug command and input text
String debugScript = "./testscript";
String input = "The input";
// Launch failed map task and run debug script
String result = launchFailMapAndDebug(conf,inDir,
outDir,debugDir, debugScript, input);
// Assert the output of debug script.
assertTrue(result.contains("Test Script\nBailing out"));
} finally {
// close file system and shut down dfs and mapred cluster
try {
if (fileSys != null) {
fileSys.close();
}
if (dfs != null) {
dfs.shutdown();
}
if (mr != null) {
mr.shutdown();
}
} catch (IOException ioe) {
LOG.info("IO exception in closing file system:"+ioe.getMessage(), ioe);
}
}
}
public static void main(String args[]){
TestMiniMRMapRedDebugScript tmds = new TestMiniMRMapRedDebugScript();
try {
tmds.testMapDebugScript();
} catch (Exception e) {
LOG.error("Exception in test: "+e.getMessage(), e);
}
}
}