/**
* 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 java.io.*;
import java.util.*;
import junit.framework.TestCase;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.dfs.MiniDFSCluster;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.examples.WordCount;
/**
* A JUnit test to test Mini Map-Reduce Cluster with Mini-DFS.
*
* @author Milind Bhandarkar
*/
public class TestMiniMRWithDFS extends TestCase {
private static final Log LOG =
LogFactory.getLog(TestMiniMRWithDFS.class.getName());
static final int NUM_MAPS = 10;
static final int NUM_SAMPLES = 100000;
public static String launchWordCount(JobConf conf,
String input,
int numMaps,
int numReduces) throws IOException {
final Path inDir = new Path("/testing/wc/input");
final Path outDir = new Path("/testing/wc/output");
FileSystem fs = FileSystem.get(conf);
fs.delete(outDir);
if (!fs.mkdirs(inDir)) {
throw new IOException("Mkdirs failed to create " + inDir.toString());
}
{
DataOutputStream file = fs.create(new Path(inDir, "part-0"));
file.writeBytes(input);
file.close();
}
conf.setJobName("wordcount");
conf.setInputFormat(TextInputFormat.class);
// the keys are words (strings)
conf.setOutputKeyClass(Text.class);
// the values are counts (ints)
conf.setOutputValueClass(IntWritable.class);
conf.setMapperClass(WordCount.MapClass.class);
conf.setCombinerClass(WordCount.Reduce.class);
conf.setReducerClass(WordCount.Reduce.class);
conf.setInputPath(inDir);
conf.setOutputPath(outDir);
conf.setNumMapTasks(numMaps);
conf.setNumReduceTasks(numReduces);
JobClient.runJob(conf);
return readOutput(outDir, conf);
}
public static String readOutput(Path outDir,
JobConf conf) throws IOException {
FileSystem fs = outDir.getFileSystem(conf);
StringBuffer result = new StringBuffer();
{
Path[] fileList = fs.listPaths(outDir);
for(int i=0; i < fileList.length; ++i) {
BufferedReader file =
new BufferedReader(new InputStreamReader(fs.open(fileList[i])));
String line = file.readLine();
while (line != null) {
result.append(line);
result.append("\n");
line = file.readLine();
}
file.close();
}
}
return result.toString();
}
/**
* Make sure that there are exactly the directories that we expect to find.
* @param mr the map-reduce cluster
* @param taskDirs the task ids that should be present
*/
private static void checkTaskDirectories(MiniMRCluster mr,
String[] jobIds,
String[] taskDirs) {
mr.waitUntilIdle();
int trackers = mr.getNumTaskTrackers();
List neededDirs = new ArrayList(Arrays.asList(taskDirs));
boolean[] found = new boolean[taskDirs.length];
for(int i=0; i < trackers; ++i) {
int numNotDel = 0;
File localDir = new File(mr.getTaskTrackerLocalDir(i));
LOG.debug("Tracker directory: " + localDir);
File trackerDir = new File(localDir, "taskTracker");
assertTrue("local dir " + localDir + " does not exist.",
localDir.isDirectory());
assertTrue("task tracker dir " + trackerDir + " does not exist.",
trackerDir.isDirectory());
String contents[] = localDir.list();
String trackerContents[] = trackerDir.list();
for(int j=0; j < contents.length; ++j) {
System.out.println("Local " + localDir + ": " + contents[j]);
}
for(int j=0; j < trackerContents.length; ++j) {
System.out.println("Local jobcache " + trackerDir + ": " + trackerContents[j]);
}
for(int fileIdx = 0; fileIdx < contents.length; ++fileIdx) {
String name = contents[fileIdx];
if (!("taskTracker".equals(contents[fileIdx]))) {
LOG.debug("Looking at " + name);
int idx = neededDirs.indexOf(name);
assertTrue("Spurious directory " + name + " found in " +
localDir, idx != -1);
assertTrue("Matching output directory not found " + name +
" in " + trackerDir,
new File(new File(new File(trackerDir, "jobcache"), jobIds[idx]), name).isDirectory());
found[idx] = true;
numNotDel++;
}
}
}
for(int i=0; i< found.length; i++) {
assertTrue("Directory " + taskDirs[i] + " not found", found[i]);
}
}
public void testWithDFS() throws IOException {
MiniDFSCluster dfs = null;
MiniMRCluster mr = null;
FileSystem fileSys = null;
try {
final int taskTrackers = 4;
final int jobTrackerPort = 60050;
Configuration conf = new Configuration();
dfs = new MiniDFSCluster(65314, conf, 4, true);
fileSys = dfs.getFileSystem();
mr = new MiniMRCluster(jobTrackerPort, 50060, taskTrackers,
fileSys.getName(), true);
double estimate = PiEstimator.launch(NUM_MAPS, NUM_SAMPLES,
mr.createJobConf());
double error = Math.abs(Math.PI - estimate);
assertTrue("Error in PI estimation "+error+" exceeds 0.01", (error < 0.01));
checkTaskDirectories(mr, new String[]{}, new String[]{});
// Run a word count example
JobConf jobConf = mr.createJobConf();
// Keeping tasks that match this pattern
jobConf.setKeepTaskFilesPattern("task_[0-9]*_m_000001_.*");
String result;
result = launchWordCount(jobConf,
"The quick brown fox\nhas many silly\n" +
"red fox sox\n",
3, 1);
assertEquals("The\t1\nbrown\t1\nfox\t2\nhas\t1\nmany\t1\n" +
"quick\t1\nred\t1\nsilly\t1\nsox\t1\n", result);
checkTaskDirectories(mr, new String[]{"job_0002"}, new String[]{"task_0002_m_000001_0"});
// test with maps=0
jobConf = mr.createJobConf();
result = launchWordCount(jobConf, "owen is oom", 0, 1);
assertEquals("is\t1\noom\t1\nowen\t1\n", result);
} finally {
if (fileSys != null) { fileSys.close(); }
if (dfs != null) { dfs.shutdown(); }
if (mr != null) { mr.shutdown();
}
}
}
}