/**
* 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.mrunit.mapreduce;
import static org.apache.hadoop.mrunit.testutil.ExtendedAssert.assertListEquals;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import junit.framework.TestCase;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.Mapper.Context;
import org.apache.hadoop.mapreduce.lib.reduce.LongSumReducer;
import org.apache.hadoop.mrunit.mapreduce.TestMapDriver.ConfigurationMapper;
import org.apache.hadoop.mrunit.types.Pair;
import org.junit.Before;
import org.junit.Test;
public class TestReduceDriver extends TestCase {
private static final int IN_A = 4;
private static final int IN_B = 6;
private static final int OUT_VAL = 10;
private static final int INCORRECT_OUT = 12;
private static final int OUT_EMPTY = 0;
private Reducer<Text, LongWritable, Text, LongWritable> reducer;
private ReduceDriver<Text, LongWritable, Text, LongWritable> driver;
@Before
public void setUp() throws Exception {
reducer = new LongSumReducer<Text>();
driver = new ReduceDriver<Text, LongWritable, Text, LongWritable>(
reducer);
}
@Test
public void testRun() {
List<Pair<Text, LongWritable>> out = null;
try {
out = driver.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.run();
} catch (IOException ioe) {
fail();
}
List<Pair<Text, LongWritable>> expected =
new ArrayList<Pair<Text, LongWritable>>();
expected.add(new Pair<Text, LongWritable>(new Text("foo"),
new LongWritable(OUT_VAL)));
assertListEquals(out, expected);
}
@Test
public void testTestRun1() {
driver
.withInputKey(new Text("foo"))
.withOutput(new Text("foo"), new LongWritable(0))
.runTest();
}
@Test
public void testTestRun2() {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("foo"), new LongWritable(OUT_VAL))
.runTest();
}
@Test
public void testTestRun3() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("bar"), new LongWritable(OUT_VAL))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testTestRun4() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("foo"), new LongWritable(INCORRECT_OUT))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testTestRun5() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("foo"), new LongWritable(IN_A))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testTestRun6() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("foo"), new LongWritable(IN_A))
.withOutput(new Text("foo"), new LongWritable(IN_B))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testTestRun7() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("foo"), new LongWritable(OUT_VAL))
.withOutput(new Text("foo"), new LongWritable(OUT_VAL))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testTestRun8() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("bar"), new LongWritable(OUT_VAL))
.withOutput(new Text("foo"), new LongWritable(OUT_VAL))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testTestRun9() {
try {
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(IN_A))
.withInputValue(new LongWritable(IN_B))
.withOutput(new Text("foo"), new LongWritable(OUT_VAL))
.withOutput(new Text("bar"), new LongWritable(OUT_VAL))
.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
@Test
public void testEmptyInput() {
// (null, <empty>) will be forcibly fed as input
// since we use LongSumReducer, expect (null, 0) out.
driver
.withOutput(null, new LongWritable(OUT_EMPTY))
.runTest();
}
@Test
public void testEmptyInput2() {
// because a null key with zero inputs will be fed as input
// to this reducer, do not accept no outputs.
try {
driver.runTest();
fail();
} catch (RuntimeException re) {
// expected.
}
}
/**
* Reducer that counts its values twice; the second iteration
* according to mapreduce semantics should be empty.
*/
private static class DoubleIterReducer<K, V>
extends Reducer<K, V, K, LongWritable> {
public void reduce(K key, Iterable<V> values, Context c)
throws IOException, InterruptedException {
long count = 0;
for (V val : values) {
count++;
}
// This time around, iteration should yield no values.
for (V val : values) {
count++;
}
c.write(key, new LongWritable(count));
}
}
@Test
public void testDoubleIteration() {
reducer = new DoubleIterReducer<Text, LongWritable>();
driver = new ReduceDriver<Text, LongWritable, Text, LongWritable>(
reducer);
driver
.withInputKey(new Text("foo"))
.withInputValue(new LongWritable(1))
.withInputValue(new LongWritable(1))
.withInputValue(new LongWritable(1))
.withInputValue(new LongWritable(1))
.withOutput(new Text("foo"), new LongWritable(4))
.runTest();
}
@Test
public void testConfiguration() {
Configuration conf = new Configuration();
conf.set("TestKey", "TestValue");
ReduceDriver<NullWritable, NullWritable, NullWritable, NullWritable> confDriver
= new ReduceDriver<NullWritable, NullWritable, NullWritable, NullWritable>();
ConfigurationReducer<NullWritable, NullWritable, NullWritable, NullWritable> reducer
= new ConfigurationReducer<NullWritable, NullWritable, NullWritable, NullWritable>();
confDriver.withReducer(reducer).withConfiguration(conf).
withInput(NullWritable.get(),Arrays.asList(NullWritable.get())).
withOutput(NullWritable.get(),NullWritable.get()).runTest();
assertEquals(reducer.setupConfiguration.get("TestKey"), "TestValue");
}
/**
* Test reducer which stores the configuration object it was passed during its setup method
*/
public static class ConfigurationReducer<KEYIN, VALUEIN, KEYOUT, VALUEOUT> extends Reducer<KEYIN, VALUEIN, KEYOUT, VALUEOUT> {
public Configuration setupConfiguration;
@Override
protected void setup(Context context) throws IOException,
InterruptedException {
setupConfiguration = context.getConfiguration();
}
}
}