MAPREDUCE-4987. TestMRJobs#testDistributedCache fails on Windows due to classpath problems and unexpected behavior of symlinks (Chris Nauroth via bikas)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1470003 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.txt

@@ -134,6 +134,10 @@ Trunk (Unreleased)
     MAPREDUCE-4885. Streaming tests have multiple failures on Windows. (Chris
     Nauroth via bikas)
 
+    MAPREDUCE-4987. TestMRJobs#testDistributedCache fails on Windows due to
+    classpath problems and unexpected behavior of symlinks (Chris Nauroth via
+    bikas)
+
   BREAKDOWN OF HADOOP-8562 SUBTASKS
 
     MAPREDUCE-4739. Some MapReduce tests fail to find winutils.

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapreduce/v2/TestMRJobs.java

@@ -18,11 +18,13 @@
 
 package org.apache.hadoop.mapreduce.v2;
 
+import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.StringReader;
 import java.net.URI;
 import java.security.PrivilegedExceptionAction;
 import java.util.HashMap;
@@ -47,6 +49,7 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.RemoteIterator;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.LongWritable;
 import org.apache.hadoop.io.NullWritable;
 import org.apache.hadoop.io.Text;
@@ -71,6 +74,7 @@ import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.util.JarFinder;
+import org.apache.hadoop.util.Shell;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.junit.AfterClass;
 import org.junit.Assert;
@@ -93,13 +97,6 @@ public class TestMRJobs {
     } catch (IOException io) {
       throw new RuntimeException("problem getting local fs", io);
     }
-    try {
-      dfsCluster = new MiniDFSCluster.Builder(conf).numDataNodes(2)
-        .format(true).racks(null).build();
-      remoteFs = dfsCluster.getFileSystem();
-    } catch (IOException io) {
-      throw new RuntimeException("problem starting mini dfs cluster", io);
-    }
   }
 
   private static Path TEST_ROOT_DIR = new Path("target",
@@ -110,6 +107,13 @@ public class TestMRJobs {
 
   @BeforeClass
   public static void setup() throws IOException {
+    try {
+      dfsCluster = new MiniDFSCluster.Builder(conf).numDataNodes(2)
+        .format(true).racks(null).build();
+      remoteFs = dfsCluster.getFileSystem();
+    } catch (IOException io) {
+      throw new RuntimeException("problem starting mini dfs cluster", io);
+    }
 
     if (!(new File(MiniMRYarnCluster.APPJAR)).exists()) {
       LOG.info("MRAppJar " + MiniMRYarnCluster.APPJAR
@@ -215,7 +219,7 @@ public class TestMRJobs {
     }
   }
 
-  @Test (timeout = 30000)
+  @Test (timeout = 60000)
   public void testRandomWriter() throws IOException, InterruptedException,
       ClassNotFoundException {
     
@@ -277,7 +281,7 @@ public class TestMRJobs {
             && counters.findCounter(JobCounter.SLOTS_MILLIS_MAPS).getValue() != 0);
   }
 
-  @Test (timeout = 30000)
+  @Test (timeout = 60000)
   public void testFailingMapper() throws IOException, InterruptedException,
       ClassNotFoundException {
 
@@ -359,7 +363,7 @@ public class TestMRJobs {
     return job;
   }
 
-  //@Test (timeout = 30000)
+  //@Test (timeout = 60000)
   public void testSleepJobWithSecurityOn() throws IOException,
       InterruptedException, ClassNotFoundException {
 
@@ -467,9 +471,47 @@ public class TestMRJobs {
       // Check that the symlink for the Job Jar was created in the cwd and
       // points to the extracted directory
       File jobJarDir = new File("job.jar");
+      if (Shell.WINDOWS) {
+        Assert.assertTrue(isWindowsSymlinkedDirectory(jobJarDir));
+      } else {
         Assert.assertTrue(FileUtils.isSymlink(jobJarDir));
         Assert.assertTrue(jobJarDir.isDirectory());
       }
+    }
+
+    /**
+     * Used on Windows to determine if the specified file is a symlink that
+     * targets a directory.  On most platforms, these checks can be done using
+     * commons-io.  On Windows, the commons-io implementation is unreliable and
+     * always returns false.  Instead, this method checks the output of the dir
+     * command.  After migrating to Java 7, this method can be removed in favor
+     * of the new method java.nio.file.Files.isSymbolicLink, which is expected to
+     * work cross-platform.
+     * 
+     * @param file File to check
+     * @return boolean true if the file is a symlink that targets a directory
+     * @throws IOException thrown for any I/O error
+     */
+    private static boolean isWindowsSymlinkedDirectory(File file)
+        throws IOException {
+      String dirOut = Shell.execCommand("cmd", "/c", "dir",
+        file.getAbsoluteFile().getParent());
+      StringReader sr = new StringReader(dirOut);
+      BufferedReader br = new BufferedReader(sr);
+      try {
+        String line = br.readLine();
+        while (line != null) {
+          line = br.readLine();
+          if (line.contains(file.getName()) && line.contains("<SYMLINKD>")) {
+            return true;
+          }
+        }
+        return false;
+      } finally {
+        IOUtils.closeStream(br);
+        IOUtils.closeStream(sr);
+      }
+    }
 
     /**
      * Returns a mapping of the final component of each path to the corresponding
@@ -542,7 +584,7 @@ public class TestMRJobs {
           trackingUrl.endsWith(jobId.substring(jobId.lastIndexOf("_")) + "/"));
   }
   
-  @Test (timeout = 300000)
+  @Test (timeout = 600000)
   public void testDistributedCache() throws Exception {
     // Test with a local (file:///) Job Jar
     Path localJobJarPath = makeJobJarWithLib(TEST_ROOT_DIR.toUri().toString());