/**
* 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 junit.framework.Assert.assertEquals;
import static junit.framework.Assert.assertFalse;
import static junit.framework.Assert.fail;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.BitSet;
import java.util.List;
import java.util.Random;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.compress.CompressionCodec;
import org.apache.hadoop.io.compress.GzipCodec;
import org.apache.hadoop.mapred.lib.CombineFileSplit;
import org.apache.hadoop.mapred.lib.CombineTextInputFormat;
import org.apache.hadoop.util.ReflectionUtils;
import org.junit.Test;
public class TestCombineTextInputFormat {
private static final Log LOG =
LogFactory.getLog(TestCombineTextInputFormat.class);
private static JobConf defaultConf = new JobConf();
private static FileSystem localFs = null;
static {
try {
defaultConf.set("fs.defaultFS", "file:///");
localFs = FileSystem.getLocal(defaultConf);
} catch (IOException e) {
throw new RuntimeException("init failure", e);
}
}
@SuppressWarnings("deprecation")
private static Path workDir =
new Path(new Path(System.getProperty("test.build.data", "/tmp")),
"TestCombineTextInputFormat").makeQualified(localFs);
// A reporter that does nothing
private static final Reporter voidReporter = Reporter.NULL;
@Test(timeout=10000)
public void testFormat() throws Exception {
JobConf job = new JobConf(defaultConf);
Random random = new Random();
long seed = random.nextLong();
LOG.info("seed = "+seed);
random.setSeed(seed);
localFs.delete(workDir, true);
FileInputFormat.setInputPaths(job, workDir);
final int length = 10000;
final int numFiles = 10;
createFiles(length, numFiles, random);
// create a combined split for the files
CombineTextInputFormat format = new CombineTextInputFormat();
LongWritable key = new LongWritable();
Text value = new Text();
for (int i = 0; i < 3; i++) {
int numSplits = random.nextInt(length/20)+1;
LOG.info("splitting: requesting = " + numSplits);
InputSplit[] splits = format.getSplits(job, numSplits);
LOG.info("splitting: got = " + splits.length);
// we should have a single split as the length is comfortably smaller than
// the block size
assertEquals("We got more than one splits!", 1, splits.length);
InputSplit split = splits[0];
assertEquals("It should be CombineFileSplit",
CombineFileSplit.class, split.getClass());
// check the split
BitSet bits = new BitSet(length);
LOG.debug("split= " + split);
RecordReader<LongWritable, Text> reader =
format.getRecordReader(split, job, voidReporter);
try {
int count = 0;
while (reader.next(key, value)) {
int v = Integer.parseInt(value.toString());
LOG.debug("read " + v);
if (bits.get(v)) {
LOG.warn("conflict with " + v +
" at position "+reader.getPos());
}
assertFalse("Key in multiple partitions.", bits.get(v));
bits.set(v);
count++;
}
LOG.info("splits="+split+" count=" + count);
} finally {
reader.close();
}
assertEquals("Some keys in no partition.", length, bits.cardinality());
}
}
private static class Range {
private final int start;
private final int end;
Range(int start, int end) {
this.start = start;
this.end = end;
}
@Override
public String toString() {
return "(" + start + ", " + end + ")";
}
}
private static Range[] createRanges(int length, int numFiles, Random random) {
// generate a number of files with various lengths
Range[] ranges = new Range[numFiles];
for (int i = 0; i < numFiles; i++) {
int start = i == 0 ? 0 : ranges[i-1].end;
int end = i == numFiles - 1 ?
length :
(length/numFiles)*(2*i + 1)/2 + random.nextInt(length/numFiles) + 1;
ranges[i] = new Range(start, end);
}
return ranges;
}
private static void createFiles(int length, int numFiles, Random random)
throws IOException {
Range[] ranges = createRanges(length, numFiles, random);
for (int i = 0; i < numFiles; i++) {
Path file = new Path(workDir, "test_" + i + ".txt");
Writer writer = new OutputStreamWriter(localFs.create(file));
Range range = ranges[i];
try {
for (int j = range.start; j < range.end; j++) {
writer.write(Integer.toString(j));
writer.write("\n");
}
} finally {
writer.close();
}
}
}
private static void writeFile(FileSystem fs, Path name,
CompressionCodec codec,
String contents) throws IOException {
OutputStream stm;
if (codec == null) {
stm = fs.create(name);
} else {
stm = codec.createOutputStream(fs.create(name));
}
stm.write(contents.getBytes());
stm.close();
}
private static List<Text> readSplit(InputFormat<LongWritable,Text> format,
InputSplit split,
JobConf job) throws IOException {
List<Text> result = new ArrayList<Text>();
RecordReader<LongWritable, Text> reader =
format.getRecordReader(split, job, voidReporter);
LongWritable key = reader.createKey();
Text value = reader.createValue();
while (reader.next(key, value)) {
result.add(value);
value = reader.createValue();
}
reader.close();
return result;
}
/**
* Test using the gzip codec for reading
*/
@Test(timeout=10000)
public void testGzip() throws IOException {
JobConf job = new JobConf(defaultConf);
CompressionCodec gzip = new GzipCodec();
ReflectionUtils.setConf(gzip, job);
localFs.delete(workDir, true);
writeFile(localFs, new Path(workDir, "part1.txt.gz"), gzip,
"the quick\nbrown\nfox jumped\nover\n the lazy\n dog\n");
writeFile(localFs, new Path(workDir, "part2.txt.gz"), gzip,
"this is a test\nof gzip\n");
FileInputFormat.setInputPaths(job, workDir);
CombineTextInputFormat format = new CombineTextInputFormat();
InputSplit[] splits = format.getSplits(job, 100);
assertEquals("compressed splits == 1", 1, splits.length);
List<Text> results = readSplit(format, splits[0], job);
assertEquals("splits[0] length", 8, results.size());
final String[] firstList =
{"the quick", "brown", "fox jumped", "over", " the lazy", " dog"};
final String[] secondList = {"this is a test", "of gzip"};
String first = results.get(0).toString();
if (first.equals(firstList[0])) {
testResults(results, firstList, secondList);
} else if (first.equals(secondList[0])) {
testResults(results, secondList, firstList);
} else {
fail("unexpected first token!");
}
}
private static void testResults(List<Text> results, String[] first,
String[] second) {
for (int i = 0; i < first.length; i++) {
assertEquals("splits[0]["+i+"]", first[i], results.get(i).toString());
}
for (int i = 0; i < second.length; i++) {
int j = i + first.length;
assertEquals("splits[0]["+j+"]", second[i], results.get(j).toString());
}
}
}