org.apache.hadoop.streaming.TestStreaming.java Source code

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Here is the source code for org.apache.hadoop.streaming.TestStreaming.java

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/**
 * 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.streaming;

import junit.framework.TestCase;
import java.io.*;
import java.util.UUID;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FileUtil;

/**
 * This class tests hadoopStreaming in MapReduce local mode.
 */
public class TestStreaming extends TestCase {
    static final Log LOG = LogFactory.getLog(TestStreaming.class);

    // "map" command: grep -E (red|green|blue)
    // reduce command: uniq
    protected String inputOutputPrefix = System.getProperty("test.build.data", "/tmp") + "/"
            + UUID.randomUUID().toString();
    protected File INPUT_FILE = new File(inputOutputPrefix + "_input.txt");
    protected File OUTPUT_DIR = new File(inputOutputPrefix + "_out");
    protected String input = "roses.are.red\nviolets.are.blue\nbunnies.are.pink\n";
    // map behaves like "/usr/bin/tr . \\n"; (split words into lines)
    protected String map = StreamUtil.makeJavaCommand(TrApp.class, new String[] { ".", "\\n" });
    // reduce behave like /usr/bin/uniq. But also prepend lines with R.
    // command-line combiner does not have any effect any more.
    protected String reduce = StreamUtil.makeJavaCommand(UniqApp.class, new String[] { "R" });
    protected String outputExpect = "Rare\t\nRblue\t\nRbunnies\t\nRpink\t\nRred\t\nRroses\t\nRviolets\t\n";
    protected boolean testBytesWritable = true;

    protected StreamJob job;

    public TestStreaming() throws IOException {
        UtilTest utilTest = new UtilTest(getClass().getName());
        utilTest.checkUserDir();
        utilTest.redirectIfAntJunit();
    }

    protected void setExpectedOutput(String out) {
        outputExpect = out;
    }

    protected void setInputFile(File input) {
        INPUT_FILE = input;
    }

    protected void setOutputDir(File output) {
        OUTPUT_DIR = output;
    }

    protected void setInputString(String in) {
        input = in;
    }

    protected void setTestBytesWritable(boolean test) {
        testBytesWritable = test;
    }

    protected void createInput() throws IOException {
        DataOutputStream out = new DataOutputStream(new FileOutputStream(INPUT_FILE.getAbsoluteFile()));
        out.write(input.getBytes("UTF-8"));
        out.close();
    }

    /**
     * Different test cases should just provide a customized
     * args and optionaly INPUT_FILE, OUTPUT_DIR, input string
     * and expected output.
     * @return
     */
    protected String[] genArgs() {
        return new String[] { "-input", INPUT_FILE.getAbsolutePath(), "-output", OUTPUT_DIR.getAbsolutePath(),
                "-mapper", map, "-reducer", reduce,
                //"-verbose",
                //"-jobconf", "stream.debug=set"
                "-jobconf", "keep.failed.task.files=true", "-jobconf",
                "stream.tmpdir=" + System.getProperty("test.build.data", "/tmp") };
    }

    public void testCommandLine() throws IOException {
        // 1st test case:
        //  Both Key and Value are Text
        String[] textArgs = genArgs();
        testCommandLineInternal(textArgs);

        // 2nd Test case:
        //   Map output key/value be BytesWritable and
        //   turn on blocked map output sort
        if (testBytesWritable) {
            String[] bytesArgs = addArgs(textArgs, new String[] { "-jobconf",
                    "stream.key_value.class=BytesWritable", "-jobconf", "mapred.map.output.blockcollector=true" });
            testCommandLineInternal(bytesArgs);
        }
    }

    String[] addArgs(String[] args, String[] more_args) {
        String[] newargs = new String[args.length + more_args.length];
        System.arraycopy(args, 0, newargs, 0, args.length);
        System.arraycopy(more_args, 0, newargs, args.length, more_args.length);
        return newargs;
    }

    protected void testCommandLineInternal(String[] args) throws IOException {
        try {
            try {
                FileUtil.fullyDelete(OUTPUT_DIR.getAbsoluteFile());
            } catch (Exception e) {
            }

            createInput();
            boolean mayExit = false;

            // During tests, the default Configuration will use a local mapred
            // So don't specify -config or -cluster
            job = new StreamJob(args, mayExit);
            job.go();
            File outFile = new File(OUTPUT_DIR, "part-00000").getAbsoluteFile();
            String output = StreamUtil.slurp(outFile);
            outFile.delete();
            System.err.println("outEx1=" + outputExpect);
            System.err.println("  out1=" + output);
            assertEquals(outputExpect, output);
        } finally {
            INPUT_FILE.delete();
            FileUtil.fullyDelete(OUTPUT_DIR.getAbsoluteFile());
        }
    }

    public static void main(String[] args) throws Exception {
        new TestStreaming().testCommandLine();
    }
}