MAPREDUCE-3790 Broken pipe on streaming job can lead to truncated output for a successful job (Jason Lowe via bobby)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1294743 13f79535-47bb-0310-9956-ffa450edef68

hadoop-tools/hadoop-streaming/src/main/java/org/apache/hadoop/streaming/PipeMapRed.java

@@ -521,11 +521,15 @@ public void mapRedFinished() {
         LOG.info("mapRedFinished");
         return;
       }
-      try {
-        if (clientOut_ != null) {
+      if (clientOut_ != null) {
+        try {
           clientOut_.flush();
           clientOut_.close();
+        } catch (IOException io) {
+          LOG.warn(io);
         }
+      }
+      try {
         waitOutputThreads();
       } catch (IOException io) {
         LOG.warn(io);

hadoop-tools/hadoop-streaming/src/test/java/org/apache/hadoop/streaming/OutputOnlyApp.java

@@ -0,0 +1,38 @@
+/**
+ * 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 java.io.IOException;
+
+/**
+ * An application that outputs a specified number of lines
+ * without consuming any input.
+ */
+public class OutputOnlyApp {
+  public static void main(String[] args) throws IOException {
+    if (args.length < 1) {
+      System.err.println("Usage: OutputOnlyApp NUMRECORDS");
+      return;
+    }
+    int numRecords = Integer.parseInt(args[0]);
+    while (numRecords-- > 0) {
+      System.out.println("key\tvalue");
+    }
+  }
+}

hadoop-tools/hadoop-streaming/src/test/java/org/apache/hadoop/streaming/TestUnconsumedInput.java

@@ -0,0 +1,107 @@
+/**
+ * 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 static org.junit.Assert.*;
+
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import org.apache.commons.lang.StringUtils;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.FileUtil;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.HdfsConfiguration;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.junit.Test;
+
+public class TestUnconsumedInput {
+  protected final int EXPECTED_OUTPUT_SIZE = 10000;
+  protected File INPUT_FILE = new File("stream_uncinput_input.txt");
+  protected File OUTPUT_DIR = new File("stream_uncinput_out");
+  // map parses input lines and generates count entries for each word.
+  protected String input = "roses.are.red\nviolets.are.blue\nbunnies.are.pink\n";
+  protected String map = UtilTest.makeJavaCommand(OutputOnlyApp.class,
+      new String[]{Integer.toString(EXPECTED_OUTPUT_SIZE)});
+
+  private StreamJob job;
+
+  public TestUnconsumedInput() throws IOException
+  {
+    UtilTest utilTest = new UtilTest(getClass().getName());
+    utilTest.checkUserDir();
+    utilTest.redirectIfAntJunit();
+  }
+
+  protected void createInput() throws IOException
+  {
+      DataOutputStream out = new DataOutputStream(
+          new FileOutputStream(INPUT_FILE.getAbsoluteFile()));
+      for (int i=0; i<10000; ++i) {
+        out.write(input.getBytes("UTF-8"));
+      }
+      out.close();
+  }
+
+  protected String[] genArgs() {
+    return new String[] {
+      "-input", INPUT_FILE.getAbsolutePath(),
+      "-output", OUTPUT_DIR.getAbsolutePath(),
+      "-mapper", map,
+      "-reducer", "org.apache.hadoop.mapred.lib.IdentityReducer",
+      "-numReduceTasks", "0",
+      "-jobconf", "mapreduce.task.files.preserve.failedtasks=true",
+      "-jobconf", "stream.tmpdir="+System.getProperty("test.build.data","/tmp")
+    };
+  }
+
+  @Test
+  public void testUnconsumedInput() throws Exception
+  {
+    String outFileName = "part-00000";
+    File outFile = null;
+    try {
+      try {
+        FileUtil.fullyDelete(OUTPUT_DIR.getAbsoluteFile());
+      } catch (Exception e) {
+      }
+
+      createInput();
+
+      // setup config to ignore unconsumed input
+      Configuration conf = new Configuration();
+      conf.set("stream.minRecWrittenToEnableSkip_", "0");
+
+      job = new StreamJob();
+      job.setConf(conf);
+      int exitCode = job.run(genArgs());
+      assertEquals("Job failed", 0, exitCode);
+      outFile = new File(OUTPUT_DIR, outFileName).getAbsoluteFile();
+      String output = StreamUtil.slurp(outFile);
+      assertEquals("Output was truncated", EXPECTED_OUTPUT_SIZE,
+          StringUtils.countMatches(output, "\t"));
+    } finally {
+      INPUT_FILE.delete();
+      FileUtil.fullyDelete(OUTPUT_DIR.getAbsoluteFile());
+    }
+  }
+}