MAPREDUCE-2880. svn merge -c r1173783 --ignore-ancestry ../../trunk/

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1173792 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.txt

@@ -292,6 +292,9 @@ Release 0.23.0 - Unreleased
 
     MAPREDUCE-901. Efficient framework counters. (llu via acmurthy)
 
+    MAPREDUCE-2880. Improve classpath-construction for mapreduce AM and
+    containers. (Arun C Murthy via vinodkv)
+
   BUG FIXES
 
     MAPREDUCE-2603. Disable High-Ram emulation in system tests. 

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapred/MapReduceChildJVM.java

@@ -18,27 +18,25 @@
 
 package org.apache.hadoop.mapred;
 
-import java.io.File;
 import java.net.InetSocketAddress;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Vector;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.mapred.TaskLog.LogName;
 import org.apache.hadoop.mapreduce.ID;
-import org.apache.hadoop.util.StringUtils;
+import org.apache.hadoop.mapreduce.MRJobConfig;
+import org.apache.hadoop.mapreduce.v2.util.MRApps;
+import org.apache.hadoop.yarn.api.ApplicationConstants;
+import org.apache.hadoop.yarn.api.ApplicationConstants.Environment;
 
 public class MapReduceChildJVM {
-  private static final String SYSTEM_PATH_SEPARATOR = 
-    System.getProperty("path.separator");
 
-  private static final Log LOG = LogFactory.getLog(MapReduceChildJVM.class);
-
-  private static File getTaskLogFile(String logDir, LogName filter) {
-    return new File(logDir, filter.toString());
+  private static String getTaskLogFile(LogName filter) {
+    return ApplicationConstants.LOG_DIR_EXPANSION_VAR + Path.SEPARATOR + 
+        filter.toString();
   }
 
   private static String getChildEnv(JobConf jobConf, boolean isMap) {
@@ -50,32 +48,53 @@ public class MapReduceChildJVM {
         jobConf.get(jobConf.MAPRED_TASK_ENV));
   }
 
-  public static void setVMEnv(Map<String, String> env,
-      List<String> classPaths, String pwd, String containerLogDir,
-      String nmLdLibraryPath, Task task, CharSequence applicationTokensFile) {
-
-    JobConf conf = task.conf;
-
-    // Add classpath.
-    CharSequence cp = env.get("CLASSPATH");
-    String classpath = StringUtils.join(SYSTEM_PATH_SEPARATOR, classPaths);
-    if (null == cp) {
-      env.put("CLASSPATH", classpath);
+  private static String getChildLogLevel(JobConf conf, boolean isMap) {
+    if (isMap) {
+      return conf.get(
+          MRJobConfig.MAP_LOG_LEVEL, 
+          JobConf.DEFAULT_LOG_LEVEL.toString()
+          );
     } else {
-      env.put("CLASSPATH", classpath + SYSTEM_PATH_SEPARATOR + cp);
+      return conf.get(
+          MRJobConfig.REDUCE_LOG_LEVEL, 
+          JobConf.DEFAULT_LOG_LEVEL.toString()
+          );
     }
+  }
+  
+  public static void setVMEnv(Map<String, String> environment,
+      Task task) {
 
-    /////// Environmental variable LD_LIBRARY_PATH
-    StringBuilder ldLibraryPath = new StringBuilder();
+    JobConf conf = task.conf;
 
-    ldLibraryPath.append(nmLdLibraryPath);
-    ldLibraryPath.append(SYSTEM_PATH_SEPARATOR);
-    ldLibraryPath.append(pwd);
-    env.put("LD_LIBRARY_PATH", ldLibraryPath.toString());
-    /////// Environmental variable LD_LIBRARY_PATH
+    // Shell
+    environment.put(
+        Environment.SHELL.name(), 
+        conf.get(
+            MRJobConfig.MAPRED_ADMIN_USER_SHELL, 
+            MRJobConfig.DEFAULT_SHELL)
+            );
+    
+    // Add pwd to LD_LIBRARY_PATH, add this before adding anything else
+    MRApps.addToEnvironment(
+        environment, 
+        Environment.LD_LIBRARY_PATH.name(), 
+        Environment.PWD.$());
+
+    // Add the env variables passed by the user & admin
+    String mapredChildEnv = getChildEnv(conf, task.isMapTask());
+    MRApps.setEnvFromInputString(environment, mapredChildEnv);
+    MRApps.setEnvFromInputString(
+        environment, 
+        conf.get(
+            MRJobConfig.MAPRED_ADMIN_USER_ENV, 
+            MRJobConfig.DEFAULT_MAPRED_ADMIN_USER_ENV)
+        );
 
-    // for the child of task jvm, set hadoop.root.logger
-    env.put("HADOOP_ROOT_LOGGER", "DEBUG,CLA"); // TODO: Debug
+    // Set logging level
+    environment.put(
+        "HADOOP_ROOT_LOGGER", 
+        getChildLogLevel(conf, task.isMapTask()) + ",CLA"); 
 
     // TODO: The following is useful for instance in streaming tasks. Should be
     // set in ApplicationMaster's env by the RM.
@@ -89,76 +108,69 @@ public class MapReduceChildJVM {
     // properties.
     long logSize = TaskLog.getTaskLogLength(conf);
     Vector<String> logProps = new Vector<String>(4);
-    setupLog4jProperties(logProps, logSize, containerLogDir);
+    setupLog4jProperties(logProps, logSize);
     Iterator<String> it = logProps.iterator();
     StringBuffer buffer = new StringBuffer();
     while (it.hasNext()) {
       buffer.append(" " + it.next());
     }
     hadoopClientOpts = hadoopClientOpts + buffer.toString();
-    
-    env.put("HADOOP_CLIENT_OPTS", hadoopClientOpts);
+    environment.put("HADOOP_CLIENT_OPTS", hadoopClientOpts);
 
-    // add the env variables passed by the user
-    String mapredChildEnv = getChildEnv(conf, task.isMapTask());
-    if (mapredChildEnv != null && mapredChildEnv.length() > 0) {
-      String childEnvs[] = mapredChildEnv.split(",");
-      for (String cEnv : childEnvs) {
-        String[] parts = cEnv.split("="); // split on '='
-        String value = (String) env.get(parts[0]);
-        if (value != null) {
-          // replace $env with the child's env constructed by tt's
-          // example LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/tmp
-          value = parts[1].replace("$" + parts[0], value);
-        } else {
-          // this key is not configured by the tt for the child .. get it 
-          // from the tt's env
-          // example PATH=$PATH:/tmp
-          value = System.getenv(parts[0]); // Get from NM?
-          if (value != null) {
-            // the env key is present in the tt's env
-            value = parts[1].replace("$" + parts[0], value);
-          } else {
-            // the env key is note present anywhere .. simply set it
-            // example X=$X:/tmp or X=/tmp
-            value = parts[1].replace("$" + parts[0], "");
-          }
-        }
-        env.put(parts[0], value);
-      }
-    }
-
-    //This should not be set here (If an OS check is requied. moved to ContainerLuanch)
-    // env.put("JVM_PID", "`echo $$`");
-
-    env.put(Constants.STDOUT_LOGFILE_ENV,
-        getTaskLogFile(containerLogDir, TaskLog.LogName.STDOUT).toString());
-    env.put(Constants.STDERR_LOGFILE_ENV,
-        getTaskLogFile(containerLogDir, TaskLog.LogName.STDERR).toString());
+    // Add stdout/stderr env
+    environment.put(
+        MRJobConfig.STDOUT_LOGFILE_ENV,
+        getTaskLogFile(TaskLog.LogName.STDOUT)
+        );
+    environment.put(
+        MRJobConfig.STDERR_LOGFILE_ENV,
+        getTaskLogFile(TaskLog.LogName.STDERR)
+        );
   }
 
   private static String getChildJavaOpts(JobConf jobConf, boolean isMapTask) {
+    String userClasspath = "";
+    String adminClasspath = "";
     if (isMapTask) {
-      return jobConf.get(JobConf.MAPRED_MAP_TASK_JAVA_OPTS, jobConf.get(
-          JobConf.MAPRED_TASK_JAVA_OPTS,
-          JobConf.DEFAULT_MAPRED_TASK_JAVA_OPTS));
+      userClasspath = 
+          jobConf.get(
+              JobConf.MAPRED_MAP_TASK_JAVA_OPTS, 
+              jobConf.get(
+                  JobConf.MAPRED_TASK_JAVA_OPTS, 
+                  JobConf.DEFAULT_MAPRED_TASK_JAVA_OPTS)
+          );
+      adminClasspath = 
+          jobConf.get(
+              MRJobConfig.MAPRED_MAP_ADMIN_JAVA_OPTS,
+              MRJobConfig.DEFAULT_MAPRED_ADMIN_JAVA_OPTS);
+    } else {
+      userClasspath =
+          jobConf.get(
+              JobConf.MAPRED_REDUCE_TASK_JAVA_OPTS, 
+              jobConf.get(
+                  JobConf.MAPRED_TASK_JAVA_OPTS,
+                  JobConf.DEFAULT_MAPRED_TASK_JAVA_OPTS)
+              );
+      adminClasspath =
+          jobConf.get(
+              MRJobConfig.MAPRED_REDUCE_ADMIN_JAVA_OPTS,
+              MRJobConfig.DEFAULT_MAPRED_ADMIN_JAVA_OPTS);
     }
-    return jobConf
-        .get(JobConf.MAPRED_REDUCE_TASK_JAVA_OPTS, jobConf.get(
-            JobConf.MAPRED_TASK_JAVA_OPTS,
-            JobConf.DEFAULT_MAPRED_TASK_JAVA_OPTS));
+    
+    // Add admin classpath first so it can be overridden by user.
+    return adminClasspath + " " + userClasspath;
   }
 
   private static void setupLog4jProperties(Vector<String> vargs,
-      long logSize, String containerLogDir) {
+      long logSize) {
     vargs.add("-Dlog4j.configuration=container-log4j.properties");
-    vargs.add("-Dhadoop.yarn.mr.containerLogDir=" + containerLogDir);
+    vargs.add("-Dhadoop.yarn.mr.containerLogDir=" + ApplicationConstants.LOG_DIR_EXPANSION_VAR);
     vargs.add("-Dhadoop.yarn.mr.totalLogFileSize=" + logSize);
   }
 
   public static List<String> getVMCommand(
-      InetSocketAddress taskAttemptListenerAddr, Task task, String javaHome,
-      String workDir, String logDir, String childTmpDir, ID jvmID) {
+      InetSocketAddress taskAttemptListenerAddr, Task task, 
+      ID jvmID) {
 
     TaskAttemptID attemptID = task.getTaskID();
     JobConf conf = task.conf;
@@ -166,7 +178,7 @@ public class MapReduceChildJVM {
     Vector<String> vargs = new Vector<String>(8);
 
     vargs.add("exec");
-    vargs.add(javaHome + "/bin/java");
+    vargs.add(Environment.JAVA_HOME.$() + "/bin/java");
 
     // Add child (task) java-vm options.
     //
@@ -199,44 +211,26 @@ public class MapReduceChildJVM {
     String javaOpts = getChildJavaOpts(conf, task.isMapTask());
     javaOpts = javaOpts.replace("@taskid@", attemptID.toString());
     String [] javaOptsSplit = javaOpts.split(" ");
-    
-    // Add java.library.path; necessary for loading native libraries.
-    //
-    // 1. We add the 'cwd' of the task to it's java.library.path to help 
-    //    users distribute native libraries via the DistributedCache.
-    // 2. The user can also specify extra paths to be added to the 
-    //    java.library.path via mapred.{map|reduce}.child.java.opts.
-    //
-    String libraryPath = workDir;
-    boolean hasUserLDPath = false;
-    for(int i=0; i<javaOptsSplit.length ;i++) { 
-      if(javaOptsSplit[i].startsWith("-Djava.library.path=")) {
-        // TODO: Does the above take care of escaped space chars
-        javaOptsSplit[i] += SYSTEM_PATH_SEPARATOR + libraryPath;
-        hasUserLDPath = true;
-        break;
-      }
-    }
-    if(!hasUserLDPath) {
-      vargs.add("-Djava.library.path=" + libraryPath);
-    }
     for (int i = 0; i < javaOptsSplit.length; i++) {
       vargs.add(javaOptsSplit[i]);
     }
 
-    if (childTmpDir != null) {
-      vargs.add("-Djava.io.tmpdir=" + childTmpDir);
-    }
+    String childTmpDir = Environment.PWD.$() + Path.SEPARATOR + "tmp";
+    vargs.add("-Djava.io.tmpdir=" + childTmpDir);
 
     // Setup the log4j prop
     long logSize = TaskLog.getTaskLogLength(conf);
-    setupLog4jProperties(vargs, logSize, logDir);
+    setupLog4jProperties(vargs, logSize);
 
     if (conf.getProfileEnabled()) {
       if (conf.getProfileTaskRange(task.isMapTask()
                                    ).isIncluded(task.getPartition())) {
-        File prof = getTaskLogFile(logDir, TaskLog.LogName.PROFILE);
-        vargs.add(String.format(conf.getProfileParams(), prof.toString()));
+        vargs.add(
+            String.format(
+                conf.getProfileParams(), 
+                getTaskLogFile(TaskLog.LogName.PROFILE)
+                )
+            );
       }
     }
 
@@ -249,8 +243,8 @@ public class MapReduceChildJVM {
 
     // Finally add the jvmID
     vargs.add(String.valueOf(jvmID.getId()));
-    vargs.add("1>" + getTaskLogFile(logDir, TaskLog.LogName.STDERR));
-    vargs.add("2>" + getTaskLogFile(logDir, TaskLog.LogName.STDOUT));
+    vargs.add("1>" + getTaskLogFile(TaskLog.LogName.STDERR));
+    vargs.add("2>" + getTaskLogFile(TaskLog.LogName.STDOUT));
 
     // Final commmand
     StringBuilder mergedCommand = new StringBuilder();

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapred/YarnChild.java

@@ -47,7 +47,6 @@ import org.apache.hadoop.mapreduce.filecache.DistributedCache;
 import org.apache.hadoop.mapreduce.security.TokenCache;
 import org.apache.hadoop.mapreduce.security.token.JobTokenIdentifier;
 import org.apache.hadoop.mapreduce.security.token.JobTokenSecretManager;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
 import org.apache.hadoop.metrics2.source.JvmMetrics;
 import org.apache.hadoop.security.Credentials;
@@ -71,7 +70,7 @@ class YarnChild {
     LOG.debug("Child starting");
 
     final JobConf defaultConf = new JobConf();
-    defaultConf.addResource(MRConstants.JOB_CONF_FILE);
+    defaultConf.addResource(MRJobConfig.JOB_CONF_FILE);
     UserGroupInformation.setConfiguration(defaultConf);
 
     String host = args[0];
@@ -238,7 +237,7 @@ class YarnChild {
 
   private static JobConf configureTask(Task task, Credentials credentials,
       Token<JobTokenIdentifier> jt) throws IOException {
-    final JobConf job = new JobConf(MRConstants.JOB_CONF_FILE);
+    final JobConf job = new JobConf(MRJobConfig.JOB_CONF_FILE);
     job.setCredentials(credentials);
     // set tcp nodelay
     job.setBoolean("ipc.client.tcpnodelay", true);
@@ -260,7 +259,7 @@ class YarnChild {
 
     // Overwrite the localized task jobconf which is linked to in the current
     // work-dir.
-    Path localTaskFile = new Path(Constants.JOBFILE);
+    Path localTaskFile = new Path(MRJobConfig.JOB_CONF_FILE);
     writeLocalJobFile(localTaskFile, job);
     task.setJobFile(localTaskFile.toString());
     task.setConf(job);

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/MRAppMaster.java

@@ -39,7 +39,6 @@ import org.apache.hadoop.mapreduce.MRJobConfig;
 import org.apache.hadoop.mapreduce.jobhistory.JobHistoryEvent;
 import org.apache.hadoop.mapreduce.jobhistory.JobHistoryEventHandler;
 import org.apache.hadoop.mapreduce.security.token.JobTokenSecretManager;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.api.records.JobId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskId;
 import org.apache.hadoop.mapreduce.v2.app.client.ClientService;
@@ -243,10 +242,10 @@ public class MRAppMaster extends CompositeService {
         // Read the file-system tokens from the localized tokens-file.
         Path jobSubmitDir = 
             FileContext.getLocalFSFileContext().makeQualified(
-                new Path(new File(MRConstants.JOB_SUBMIT_DIR)
+                new Path(new File(MRJobConfig.JOB_SUBMIT_DIR)
                     .getAbsolutePath()));
         Path jobTokenFile = 
-            new Path(jobSubmitDir, MRConstants.APPLICATION_TOKENS_FILE);
+            new Path(jobSubmitDir, MRJobConfig.APPLICATION_TOKENS_FILE);
         fsTokens.addAll(Credentials.readTokenStorageFile(jobTokenFile, conf));
         LOG.info("jobSubmitDir=" + jobSubmitDir + " jobTokenFile="
             + jobTokenFile);
@@ -658,7 +657,7 @@ public class MRAppMaster extends CompositeService {
       Runtime.getRuntime().addShutdownHook(
           new CompositeServiceShutdownHook(appMaster));
       YarnConfiguration conf = new YarnConfiguration(new JobConf());
-      conf.addResource(new Path(MRConstants.JOB_CONF_FILE));
+      conf.addResource(new Path(MRJobConfig.JOB_CONF_FILE));
       conf.set(MRJobConfig.USER_NAME, 
           System.getProperty("user.name")); 
       UserGroupInformation.setConfiguration(conf);

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/job/impl/JobImpl.java

@@ -42,6 +42,7 @@ import org.apache.hadoop.io.Text;
 import org.apache.hadoop.mapred.FileOutputCommitter;
 import org.apache.hadoop.mapred.JobACLsManager;
 import org.apache.hadoop.mapred.JobConf;
+import org.apache.hadoop.mapred.MapReduceChildJVM;
 import org.apache.hadoop.mapreduce.JobACL;
 import org.apache.hadoop.mapreduce.JobContext;
 import org.apache.hadoop.mapreduce.MRJobConfig;
@@ -64,7 +65,6 @@ import org.apache.hadoop.mapreduce.split.JobSplit.TaskSplitMetaInfo;
 import org.apache.hadoop.mapreduce.split.SplitMetaInfoReader;
 import org.apache.hadoop.mapreduce.task.JobContextImpl;
 import org.apache.hadoop.mapreduce.task.TaskAttemptContextImpl;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.api.records.Counter;
 import org.apache.hadoop.mapreduce.v2.api.records.CounterGroup;
 import org.apache.hadoop.mapreduce.v2.api.records.Counters;
@@ -1007,7 +1007,7 @@ public class JobImpl implements org.apache.hadoop.mapreduce.v2.app.job.Job,
           FileSystem.get(job.conf).makeQualified(
               new Path(path, oldJobIDString));
       job.remoteJobConfFile =
-          new Path(job.remoteJobSubmitDir, MRConstants.JOB_CONF_FILE);
+          new Path(job.remoteJobSubmitDir, MRJobConfig.JOB_CONF_FILE);
 
       // Prepare the TaskAttemptListener server for authentication of Containers
       // TaskAttemptListener gets the information via jobTokenSecretManager.
@@ -1033,7 +1033,7 @@ public class JobImpl implements org.apache.hadoop.mapreduce.v2.app.job.Job,
 
       Path remoteJobTokenFile =
           new Path(job.remoteJobSubmitDir,
-              MRConstants.APPLICATION_TOKENS_FILE);
+              MRJobConfig.APPLICATION_TOKENS_FILE);
       tokenStorage.writeTokenStorageFile(remoteJobTokenFile, job.conf);
       LOG.info("Writing back the job-token file on the remote file system:"
           + remoteJobTokenFile.toString());

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/job/impl/TaskAttemptImpl.java

@@ -21,7 +21,6 @@ package org.apache.hadoop.mapreduce.v2.app.job.impl;
 import java.io.File;
 import java.io.IOException;
 import java.net.InetSocketAddress;
-import java.net.URI;
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -62,7 +61,6 @@ import org.apache.hadoop.mapreduce.jobhistory.TaskAttemptStartedEvent;
 import org.apache.hadoop.mapreduce.jobhistory.TaskAttemptUnsuccessfulCompletionEvent;
 import org.apache.hadoop.mapreduce.security.TokenCache;
 import org.apache.hadoop.mapreduce.security.token.JobTokenIdentifier;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.api.records.Counter;
 import org.apache.hadoop.mapreduce.v2.api.records.Counters;
 import org.apache.hadoop.mapreduce.v2.api.records.Phase;
@@ -103,6 +101,7 @@ import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.yarn.Clock;
 import org.apache.hadoop.yarn.YarnException;
 import org.apache.hadoop.yarn.api.ApplicationConstants;
+import org.apache.hadoop.yarn.api.ApplicationConstants.Environment;
 import org.apache.hadoop.yarn.api.records.ContainerId;
 import org.apache.hadoop.yarn.api.records.ContainerLaunchContext;
 import org.apache.hadoop.yarn.api.records.ContainerToken;
@@ -117,7 +116,6 @@ import org.apache.hadoop.yarn.state.InvalidStateTransitonException;
 import org.apache.hadoop.yarn.state.SingleArcTransition;
 import org.apache.hadoop.yarn.state.StateMachine;
 import org.apache.hadoop.yarn.state.StateMachineFactory;
-import org.apache.hadoop.yarn.util.BuilderUtils;
 import org.apache.hadoop.yarn.util.ConverterUtils;
 import org.apache.hadoop.yarn.util.RackResolver;
 
@@ -518,8 +516,8 @@ public abstract class TaskAttemptImpl implements
         return initialClasspath;
       }
       Map<String, String> env = new HashMap<String, String>();
-      MRApps.setInitialClasspath(env);
-      initialClasspath = env.get(MRApps.CLASSPATH);
+      MRApps.setClasspath(env);
+      initialClasspath = env.get(Environment.CLASSPATH.name());
       initialClasspathFlag.set(true);
       return initialClasspath;
     }
@@ -531,16 +529,18 @@ public abstract class TaskAttemptImpl implements
    */
   private ContainerLaunchContext createContainerLaunchContext() {
 
-    ContainerLaunchContext container =
-        recordFactory.newRecordInstance(ContainerLaunchContext.class);
-
     // Application resources
     Map<String, LocalResource> localResources = 
         new HashMap<String, LocalResource>();
     
     // Application environment
     Map<String, String> environment = new HashMap<String, String>();
-    
+
+    // Service data
+    Map<String, ByteBuffer> serviceData = new HashMap<String, ByteBuffer>();
+
+    // Tokens
+    ByteBuffer tokens = ByteBuffer.wrap(new byte[]{});
     try {
       FileSystem remoteFS = FileSystem.get(conf);
 
@@ -550,7 +550,7 @@ public abstract class TaskAttemptImpl implements
               MRJobConfig.JAR))).makeQualified(remoteFS.getUri(), 
                                                remoteFS.getWorkingDirectory());
         localResources.put(
-            MRConstants.JOB_JAR,
+            MRJobConfig.JOB_JAR,
             createLocalResource(remoteFS, recordFactory, remoteJobJar,
                 LocalResourceType.FILE, LocalResourceVisibility.APPLICATION));
         LOG.info("The job-jar file on the remote FS is "
@@ -570,9 +570,9 @@ public abstract class TaskAttemptImpl implements
       Path remoteJobSubmitDir =
           new Path(path, oldJobId.toString());
       Path remoteJobConfPath = 
-          new Path(remoteJobSubmitDir, MRConstants.JOB_CONF_FILE);
+          new Path(remoteJobSubmitDir, MRJobConfig.JOB_CONF_FILE);
       localResources.put(
-          MRConstants.JOB_CONF_FILE,
+          MRJobConfig.JOB_CONF_FILE,
           createLocalResource(remoteFS, recordFactory, remoteJobConfPath,
               LocalResourceType.FILE, LocalResourceVisibility.APPLICATION));
       LOG.info("The job-conf file on the remote FS is "
@@ -580,12 +580,8 @@ public abstract class TaskAttemptImpl implements
       // //////////// End of JobConf setup
 
       // Setup DistributedCache
-      MRApps.setupDistributedCache(conf, localResources, environment);
+      MRApps.setupDistributedCache(conf, localResources);
 
-      // Set local-resources and environment
-      container.setLocalResources(localResources);
-      container.setEnvironment(environment);
-      
       // Setup up tokens
       Credentials taskCredentials = new Credentials();
 
@@ -606,52 +602,43 @@ public abstract class TaskAttemptImpl implements
       LOG.info("Size of containertokens_dob is "
           + taskCredentials.numberOfTokens());
       taskCredentials.writeTokenStorageToStream(containerTokens_dob);
-      container.setContainerTokens(
+      tokens = 
           ByteBuffer.wrap(containerTokens_dob.getData(), 0,
-              containerTokens_dob.getLength()));
+              containerTokens_dob.getLength());
 
       // Add shuffle token
       LOG.info("Putting shuffle token in serviceData");
-      Map<String, ByteBuffer> serviceData = new HashMap<String, ByteBuffer>();
       serviceData.put(ShuffleHandler.MAPREDUCE_SHUFFLE_SERVICEID,
           ShuffleHandler.serializeServiceData(jobToken));
-      container.setServiceData(serviceData);
 
-      MRApps.addToClassPath(container.getEnvironment(), getInitialClasspath());
+      MRApps.addToEnvironment(
+          environment,  
+          Environment.CLASSPATH.name(), 
+          getInitialClasspath());
     } catch (IOException e) {
       throw new YarnException(e);
     }
-    
-    container.setContainerId(containerID);
-    container.setUser(conf.get(MRJobConfig.USER_NAME)); // TODO: Fix
-
-    File workDir = new File("$PWD"); // Will be expanded by the shell.
-    String containerLogDir =
-        new File(ApplicationConstants.LOG_DIR_EXPANSION_VAR).toString();
-    String childTmpDir = new File(workDir, "tmp").toString();
-    String javaHome = "${JAVA_HOME}"; // Will be expanded by the shell.
-    String nmLdLibraryPath = "{LD_LIBRARY_PATH}"; // Expanded by the shell?
-    List<String> classPaths = new ArrayList<String>();
-
-    String localizedApplicationTokensFile =
-        new File(workDir, MRConstants.APPLICATION_TOKENS_FILE).toString();
-    classPaths.add(MRConstants.JOB_JAR);
-    classPaths.add(MRConstants.YARN_MAPREDUCE_APP_JAR_PATH);
-    classPaths.add(workDir.toString()); // TODO
-
-    // Construct the actual Container
-    container.setCommands(MapReduceChildJVM.getVMCommand(
-        taskAttemptListener.getAddress(), remoteTask, javaHome,
-        workDir.toString(), containerLogDir, childTmpDir, jvmID));
 
-    MapReduceChildJVM.setVMEnv(container.getEnvironment(), classPaths,
-        workDir.toString(), containerLogDir, nmLdLibraryPath, remoteTask,
-        localizedApplicationTokensFile);
+    // Setup environment
+    MapReduceChildJVM.setVMEnv(environment, remoteTask);
 
+    // Set up the launch command
+    List<String> commands = MapReduceChildJVM.getVMCommand(
+        taskAttemptListener.getAddress(), remoteTask,
+        jvmID);
+    
     // Construct the actual Container
+    ContainerLaunchContext container =
+        recordFactory.newRecordInstance(ContainerLaunchContext.class);
     container.setContainerId(containerID);
     container.setUser(conf.get(MRJobConfig.USER_NAME));
     container.setResource(assignedCapability);
+    container.setLocalResources(localResources);
+    container.setEnvironment(environment);
+    container.setCommands(commands);
+    container.setServiceData(serviceData);
+    container.setContainerTokens(tokens);
+    
     return container;
   }
 

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/speculate/DefaultSpeculator.java

@@ -35,7 +35,6 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.mapreduce.MRJobConfig;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.api.records.JobId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptState;
@@ -87,7 +86,7 @@ public class DefaultSpeculator extends AbstractService implements
   private final ConcurrentMap<JobId, AtomicInteger> reduceContainerNeeds
       = new ConcurrentHashMap<JobId, AtomicInteger>();
 
-  private final Set<TaskId> mayHaveSpeculated = new HashSet();
+  private final Set<TaskId> mayHaveSpeculated = new HashSet<TaskId>();
 
   private final Configuration conf;
   private AppContext context;

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-common/src/main/java/org/apache/hadoop/mapreduce/v2/MRConstants.java

@@ -1,50 +0,0 @@
-/**
-* 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.mapreduce.v2;
-
-
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.classification.InterfaceStability;
-
-@InterfaceAudience.Private
-@InterfaceStability.Evolving
-public interface MRConstants {
-  // This should be the directory where splits file gets localized on the node
-  // running ApplicationMaster.
-  public static final String JOB_SUBMIT_DIR = "jobSubmitDir";
-  
-  // This should be the name of the localized job-configuration file on the node
-  // running ApplicationMaster and Task
-  public static final String JOB_CONF_FILE = "job.xml";
-  // This should be the name of the localized job-jar file on the node running
-  // individual containers/tasks.
-  public static final String JOB_JAR = "job.jar";
-
-  public static final String HADOOP_MAPREDUCE_CLIENT_APP_JAR_NAME =
-      "hadoop-mapreduce-client-app-0.23.0-SNAPSHOT.jar";
-
-  public static final String YARN_MAPREDUCE_APP_JAR_PATH =
-    "$YARN_HOME/modules/" + HADOOP_MAPREDUCE_CLIENT_APP_JAR_NAME;
-
-  // The token file for the application. Should contain tokens for access to
-  // remote file system and may optionally contain application specific tokens.
-  // For now, generated by the AppManagers and used by NodeManagers and the
-  // Containers.
-  public static final String APPLICATION_TOKENS_FILE = "appTokens";
-}

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-common/src/main/java/org/apache/hadoop/mapreduce/v2/util/MRApps.java

@@ -39,14 +39,14 @@ import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.mapreduce.MRJobConfig;
 import org.apache.hadoop.mapreduce.filecache.DistributedCache;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.api.records.JobId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptState;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskType;
-import org.apache.hadoop.util.Shell.ShellCommandExecutor;
 import org.apache.hadoop.yarn.YarnException;
+import org.apache.hadoop.yarn.api.ApplicationConstants.Environment;
+import org.apache.hadoop.yarn.api.ApplicationConstants;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.LocalResource;
 import org.apache.hadoop.yarn.api.records.LocalResourceType;
@@ -167,7 +167,7 @@ public class MRApps extends Apps {
     return TaskAttemptStateUI.valueOf(attemptStateStr);
   }
 
-  public static void setInitialClasspath(
+  private static void setMRFrameworkClasspath(
       Map<String, String> environment) throws IOException {
     InputStream classpathFileStream = null;
     BufferedReader reader = null;
@@ -182,30 +182,17 @@ public class MRApps extends Apps {
       reader = new BufferedReader(new InputStreamReader(classpathFileStream));
       String cp = reader.readLine();
       if (cp != null) {
-        addToClassPath(environment, cp.trim());
+        addToEnvironment(environment, Environment.CLASSPATH.name(), cp.trim());
       }
       // Put the file itself on classpath for tasks.
-      addToClassPath(environment,
+      addToEnvironment(
+          environment,
+          Environment.CLASSPATH.name(),
           thisClassLoader.getResource(mrAppGeneratedClasspathFile).getFile());
 
-      // If runtime env is different.
-      if (System.getenv().get("YARN_HOME") != null) {
-        ShellCommandExecutor exec =
-            new ShellCommandExecutor(new String[] {
-                System.getenv().get("YARN_HOME") + "/bin/yarn",
-            "classpath" });
-        exec.execute();
-        addToClassPath(environment, exec.getOutput().trim());
-      }
-
-      // Get yarn mapreduce-app classpath
-      if (System.getenv().get("HADOOP_MAPRED_HOME")!= null) {
-        ShellCommandExecutor exec =
-            new ShellCommandExecutor(new String[] {
-                System.getenv().get("HADOOP_MAPRED_HOME") + "/bin/mapred",
-            "classpath" });
-        exec.execute();
-        addToClassPath(environment, exec.getOutput().trim());
+      // Add standard Hadoop classes
+      for (String c : ApplicationConstants.APPLICATION_CLASSPATH) {
+        addToEnvironment(environment, Environment.CLASSPATH.name(), c);
       }
     } finally {
       if (classpathFileStream != null) {
@@ -217,20 +204,35 @@ public class MRApps extends Apps {
     }
     // TODO: Remove duplicates.
   }
-
-  public static void addToClassPath(
-      Map<String, String> environment, String fileName) {
-    String classpath = environment.get(CLASSPATH);
-    if (classpath == null) {
-      classpath = fileName;
+  
+  private static final String SYSTEM_PATH_SEPARATOR = 
+      System.getProperty("path.separator");
+
+  public static void addToEnvironment(
+      Map<String, String> environment, 
+      String variable, String value) {
+    String val = environment.get(variable);
+    if (val == null) {
+      val = value;
     } else {
-      classpath = classpath + ":" + fileName;
+      val = val + SYSTEM_PATH_SEPARATOR + value;
     }
-    environment.put(CLASSPATH, classpath);
+    environment.put(variable, val);
   }
 
-  public static final String CLASSPATH = "CLASSPATH";
-
+  public static void setClasspath(Map<String, String> environment) 
+      throws IOException {
+    MRApps.addToEnvironment(
+        environment, 
+        Environment.CLASSPATH.name(), 
+        MRJobConfig.JOB_JAR);
+    MRApps.addToEnvironment(
+        environment, 
+        Environment.CLASSPATH.name(),
+        Environment.PWD.$() + Path.SEPARATOR + "*");
+    MRApps.setMRFrameworkClasspath(environment);
+  }
+  
   private static final String STAGING_CONSTANT = ".staging";
   public static Path getStagingAreaDir(Configuration conf, String user) {
     return new Path(
@@ -241,7 +243,7 @@ public class MRApps extends Apps {
   public static String getJobFile(Configuration conf, String user, 
       org.apache.hadoop.mapreduce.JobID jobId) {
     Path jobFile = new Path(MRApps.getStagingAreaDir(conf, user),
-        jobId.toString() + Path.SEPARATOR + MRConstants.JOB_CONF_FILE);
+        jobId.toString() + Path.SEPARATOR + MRJobConfig.JOB_CONF_FILE);
     return jobFile.toString();
   }
   
@@ -260,12 +262,11 @@ public class MRApps extends Apps {
 
   public static void setupDistributedCache( 
       Configuration conf, 
-      Map<String, LocalResource> localResources,
-      Map<String, String> env) 
+      Map<String, LocalResource> localResources) 
   throws IOException {
     
     // Cache archives
-    parseDistributedCacheArtifacts(conf, localResources, env, 
+    parseDistributedCacheArtifacts(conf, localResources,  
         LocalResourceType.ARCHIVE, 
         DistributedCache.getCacheArchives(conf), 
         parseTimeStamps(DistributedCache.getArchiveTimestamps(conf)), 
@@ -275,7 +276,7 @@ public class MRApps extends Apps {
     
     // Cache files
     parseDistributedCacheArtifacts(conf, 
-        localResources, env, 
+        localResources,  
         LocalResourceType.FILE, 
         DistributedCache.getCacheFiles(conf),
         parseTimeStamps(DistributedCache.getFileTimestamps(conf)),
@@ -290,7 +291,6 @@ public class MRApps extends Apps {
   private static void parseDistributedCacheArtifacts(
       Configuration conf,
       Map<String, LocalResource> localResources,
-      Map<String, String> env,
       LocalResourceType type,
       URI[] uris, long[] timestamps, long[] sizes, boolean visibilities[], 
       Path[] pathsToPutOnClasspath) throws IOException {
@@ -339,9 +339,6 @@ public class MRApps extends Apps {
                   : LocalResourceVisibility.PRIVATE,
                 sizes[i], timestamps[i])
         );
-        if (classPaths.containsKey(u.getPath())) {
-          MRApps.addToClassPath(env, linkName);
-        }
       }
     }
   }
@@ -358,6 +355,42 @@ public class MRApps extends Apps {
     }
     return result;
   }
+
+  public static void setEnvFromInputString(Map<String, String> env,
+      String envString) {
+    if (envString != null && envString.length() > 0) {
+      String childEnvs[] = envString.split(",");
+      for (String cEnv : childEnvs) {
+        String[] parts = cEnv.split("="); // split on '='
+        String value = env.get(parts[0]);
+  
+        if (value != null) {
+          // Replace $env with the child's env constructed by NM's
+          // For example: LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/tmp
+          value = parts[1].replace("$" + parts[0], value);
+        } else {
+          // example PATH=$PATH:/tmp
+          value = System.getenv(parts[0]);
+          if (value != null) {
+            // the env key is present in the tt's env
+            value = parts[1].replace("$" + parts[0], value);
+          } else {
+            // check for simple variable substitution
+            // for e.g. ROOT=$HOME
+            String envValue = System.getenv(parts[1].substring(1)); 
+            if (envValue != null) {
+              value = envValue;
+            } else {
+              // the env key is note present anywhere .. simply set it
+              // example X=$X:/tmp or X=/tmp
+              value = parts[1].replace("$" + parts[0], "");
+            }
+          }
+        }
+        addToEnvironment(env, parts[0], value);
+      }
+    }
+  }
   
 
 

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-common/src/test/java/org/apache/hadoop/mapreduce/v2/util/TestMRApps.java

@@ -25,7 +25,6 @@ import org.apache.hadoop.mapreduce.v2.api.records.JobId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskId;
 import org.apache.hadoop.mapreduce.v2.api.records.TaskType;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.util.MRApps;
 import org.apache.hadoop.yarn.YarnException;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
@@ -115,7 +114,8 @@ public class TestMRApps {
   @Test public void testGetJobFileWithUser() {
     Configuration conf = new Configuration();
     conf.set(MRJobConfig.MR_AM_STAGING_DIR, "/my/path/to/staging");
-    String jobFile = MRApps.getJobFile(conf, "dummy-user", new JobID("dummy-job", 12345));
+    String jobFile = MRApps.getJobFile(conf, "dummy-user", 
+        new JobID("dummy-job", 12345));
     assertNotNull("getJobFile results in null.", jobFile);
     assertEquals("jobFile with specified user is not as expected.",
         "/my/path/to/staging/dummy-user/.staging/job_dummy-job_12345/job.xml", jobFile);

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/BackupStore.java

@@ -41,6 +41,7 @@ import org.apache.hadoop.mapred.IFile.Reader;
 import org.apache.hadoop.mapred.IFile.Writer;
 import org.apache.hadoop.mapred.Merger.Segment;
 import org.apache.hadoop.mapreduce.MRConfig;
+import org.apache.hadoop.mapreduce.MRJobConfig;
 import org.apache.hadoop.mapreduce.TaskAttemptID;
 
 /**
@@ -560,7 +561,7 @@ public class BackupStore<K,V> {
 
     private Writer<K,V> createSpillFile() throws IOException {
       Path tmp =
-          new Path(Constants.OUTPUT + "/backup_" + tid.getId() + "_"
+          new Path(MRJobConfig.OUTPUT + "/backup_" + tid.getId() + "_"
               + (spillNumber++) + ".out");
 
       LOG.info("Created file: " + tmp);

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/Constants.java

@@ -1,27 +0,0 @@
-/**
- * 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;
-
-public class Constants {
-  static final String OUTPUT = "output";
-  public static final String HADOOP_WORK_DIR = "HADOOP_WORK_DIR";
-  public static final String JOBFILE = "job.xml";
-  public static final String STDOUT_LOGFILE_ENV = "STDOUT_LOGFILE_ENV";
-  public static final String STDERR_LOGFILE_ENV = "STDERR_LOGFILE_ENV";
-}

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/JobConf.java

@@ -348,6 +348,7 @@ public class JobConf extends Configuration {
    */
   public static final Level DEFAULT_LOG_LEVEL = Level.INFO;
   
+  
   /**
    * Construct a map/reduce job configuration.
    */

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/MRConstants.java

@@ -17,11 +17,16 @@
  */
 package org.apache.hadoop.mapred;
 
+import org.apache.hadoop.classification.InterfaceAudience.Private;
+import org.apache.hadoop.classification.InterfaceStability.Unstable;
+
 /*******************************
  * Some handy constants
  * 
  *******************************/
-interface MRConstants {
+@Private
+@Unstable
+public class MRConstants {
   //
   // Timeouts, constants
   //
@@ -52,6 +57,4 @@ interface MRConstants {
    * The reduce task number for which this map output is being transferred
    */
   public static final String FOR_REDUCE_TASK = "for-reduce-task";
-  
-  public static final String WORKDIR = "work";
 }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/MROutputFiles.java

@@ -27,6 +27,7 @@ import org.apache.hadoop.conf.Configurable;
 import org.apache.hadoop.fs.LocalDirAllocator;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.mapreduce.MRConfig;
+import org.apache.hadoop.mapreduce.MRJobConfig;
 
 /**
  * Manipulate the working area for the transient store for maps and reduces.
@@ -54,7 +55,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getOutputFile()
       throws IOException {
-    return lDirAlloc.getLocalPathToRead(Constants.OUTPUT + Path.SEPARATOR
+    return lDirAlloc.getLocalPathToRead(MRJobConfig.OUTPUT + Path.SEPARATOR
         + MAP_OUTPUT_FILENAME_STRING, getConf());
   }
 
@@ -68,7 +69,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getOutputFileForWrite(long size)
       throws IOException {
-    return lDirAlloc.getLocalPathForWrite(Constants.OUTPUT + Path.SEPARATOR
+    return lDirAlloc.getLocalPathForWrite(MRJobConfig.OUTPUT + Path.SEPARATOR
         + MAP_OUTPUT_FILENAME_STRING, size, getConf());
   }
 
@@ -89,7 +90,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getOutputIndexFile()
       throws IOException {
-    return lDirAlloc.getLocalPathToRead(Constants.OUTPUT + Path.SEPARATOR
+    return lDirAlloc.getLocalPathToRead(MRJobConfig.OUTPUT + Path.SEPARATOR
         + MAP_OUTPUT_FILENAME_STRING + MAP_OUTPUT_INDEX_SUFFIX_STRING,
         getConf());
   }
@@ -104,7 +105,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getOutputIndexFileForWrite(long size)
       throws IOException {
-    return lDirAlloc.getLocalPathForWrite(Constants.OUTPUT + Path.SEPARATOR
+    return lDirAlloc.getLocalPathForWrite(MRJobConfig.OUTPUT + Path.SEPARATOR
         + MAP_OUTPUT_FILENAME_STRING + MAP_OUTPUT_INDEX_SUFFIX_STRING,
         size, getConf());
   }
@@ -128,7 +129,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getSpillFile(int spillNumber)
       throws IOException {
-    return lDirAlloc.getLocalPathToRead(Constants.OUTPUT + "/spill"
+    return lDirAlloc.getLocalPathToRead(MRJobConfig.OUTPUT + "/spill"
         + spillNumber + ".out", getConf());
   }
 
@@ -143,7 +144,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getSpillFileForWrite(int spillNumber, long size)
       throws IOException {
-    return lDirAlloc.getLocalPathForWrite(Constants.OUTPUT + "/spill"
+    return lDirAlloc.getLocalPathForWrite(MRJobConfig.OUTPUT + "/spill"
         + spillNumber + ".out", size, getConf());
   }
 
@@ -157,7 +158,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getSpillIndexFile(int spillNumber)
       throws IOException {
-    return lDirAlloc.getLocalPathToRead(Constants.OUTPUT + "/spill"
+    return lDirAlloc.getLocalPathToRead(MRJobConfig.OUTPUT + "/spill"
         + spillNumber + ".out.index", getConf());
   }
 
@@ -172,7 +173,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public Path getSpillIndexFileForWrite(int spillNumber, long size)
       throws IOException {
-    return lDirAlloc.getLocalPathForWrite(Constants.OUTPUT + "/spill"
+    return lDirAlloc.getLocalPathForWrite(MRJobConfig.OUTPUT + "/spill"
         + spillNumber + ".out.index", size, getConf());
   }
 
@@ -187,7 +188,7 @@ public class MROutputFiles extends MapOutputFile {
   public Path getInputFile(int mapId)
       throws IOException {
     return lDirAlloc.getLocalPathToRead(String.format(
-        REDUCE_INPUT_FILE_FORMAT_STRING, Constants.OUTPUT, Integer
+        REDUCE_INPUT_FILE_FORMAT_STRING, MRJobConfig.OUTPUT, Integer
             .valueOf(mapId)), getConf());
   }
 
@@ -204,7 +205,7 @@ public class MROutputFiles extends MapOutputFile {
                                    long size)
       throws IOException {
     return lDirAlloc.getLocalPathForWrite(String.format(
-        REDUCE_INPUT_FILE_FORMAT_STRING, Constants.OUTPUT, mapId.getId()),
+        REDUCE_INPUT_FILE_FORMAT_STRING, MRJobConfig.OUTPUT, mapId.getId()),
         size, getConf());
   }
 
@@ -212,7 +213,7 @@ public class MROutputFiles extends MapOutputFile {
   @Override
   public void removeAll()
       throws IOException {
-    ((JobConf)getConf()).deleteLocalFiles(Constants.OUTPUT);
+    ((JobConf)getConf()).deleteLocalFiles(MRJobConfig.OUTPUT);
   }
 
   @Override

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/MRJobConfig.java

@@ -210,6 +210,8 @@ public interface MRJobConfig {
 
   public static final String REDUCE_LOG_LEVEL = "mapreduce.reduce.log.level";
 
+  public static final String DEFAULT_LOG_LEVEL = "INFO";
+
   public static final String REDUCE_MERGE_INMEM_THRESHOLD = "mapreduce.reduce.merge.inmem.threshold";
 
   public static final String REDUCE_INPUT_BUFFER_PERCENT = "mapreduce.reduce.input.buffer.percent";
@@ -400,4 +402,64 @@ public interface MRJobConfig {
    */
   public static final String MR_AM_CREATE_JH_INTERMEDIATE_BASE_DIR = 
     MR_AM_PREFIX + "create-intermediate-jh-base-dir";
+  
+  public static final String MAPRED_MAP_ADMIN_JAVA_OPTS =
+      "mapreduce.admin.map.child.java.opts";
+
+  public static final String MAPRED_REDUCE_ADMIN_JAVA_OPTS =
+      "mapreduce.admin.reduce.child.java.opts";
+
+  public static final String DEFAULT_MAPRED_ADMIN_JAVA_OPTS =
+      "-Djava.net.preferIPv4Stack=true " +
+          "-Dhadoop.metrics.log.level=WARN ";
+
+  public static final String MAPRED_ADMIN_USER_SHELL =
+      "mapreduce.admin.user.shell";
+
+  public static final String DEFAULT_SHELL = "/bin/bash";
+
+  public static final String MAPRED_ADMIN_USER_ENV =
+      "mapreduce.admin.user.env";
+
+  public static final String DEFAULT_MAPRED_ADMIN_USER_ENV =
+      "LD_LIBRARY_PATH=$HADOOP_COMMON_HOME/lib";
+
+  public static final String WORKDIR = "work";
+
+  public static final String OUTPUT = "output";
+
+  public static final String HADOOP_WORK_DIR = "HADOOP_WORK_DIR";
+
+  public static final String STDOUT_LOGFILE_ENV = "STDOUT_LOGFILE_ENV";
+
+  public static final String STDERR_LOGFILE_ENV = "STDERR_LOGFILE_ENV";
+
+  // This should be the directory where splits file gets localized on the node
+  // running ApplicationMaster.
+  public static final String JOB_SUBMIT_DIR = "jobSubmitDir";
+
+  // This should be the name of the localized job-configuration file on the node
+  // running ApplicationMaster and Task
+  public static final String JOB_CONF_FILE = "job.xml";
+
+  // This should be the name of the localized job-jar file on the node running
+  // individual containers/tasks.
+  public static final String JOB_JAR = "job.jar";
+
+  public static final String JOB_SPLIT = "job.split";
+
+  public static final String JOB_SPLIT_METAINFO = "job.splitmetainfo";
+
+  public static final String APPLICATION_MASTER_CLASS =
+      "org.apache.hadoop.mapreduce.v2.app.MRAppMaster";
+
+  // The token file for the application. Should contain tokens for access to
+  // remote file system and may optionally contain application specific tokens.
+  // For now, generated by the AppManagers and used by NodeManagers and the
+  // Containers.
+  public static final String APPLICATION_TOKENS_FILE = "appTokens";
+
+  public static final String MAPREDUCE_V2_CHILD_CLASS = 
+      "org.apache.hadoop.mapred.YarnChild";
+
 }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/main/java/org/apache/hadoop/mapred/ResourceMgrDelegate.java

@@ -32,12 +32,12 @@ import org.apache.hadoop.io.Text;
 import org.apache.hadoop.mapreduce.ClusterMetrics;
 import org.apache.hadoop.mapreduce.JobID;
 import org.apache.hadoop.mapreduce.JobStatus;
+import org.apache.hadoop.mapreduce.MRJobConfig;
 import org.apache.hadoop.mapreduce.QueueAclsInfo;
 import org.apache.hadoop.mapreduce.QueueInfo;
 import org.apache.hadoop.mapreduce.TaskTrackerInfo;
 import org.apache.hadoop.mapreduce.TypeConverter;
 import org.apache.hadoop.mapreduce.security.token.delegation.DelegationTokenIdentifier;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.util.MRApps;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.SecurityInfo;
@@ -254,7 +254,7 @@ public class ResourceMgrDelegate {
 
 
   public String getSystemDir() throws IOException, InterruptedException {
-    Path sysDir = new Path(MRConstants.JOB_SUBMIT_DIR);
+    Path sysDir = new Path(MRJobConfig.JOB_SUBMIT_DIR);
     //FileContext.getFileContext(conf).delete(sysDir, true);
     return sysDir.toString();
   }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/main/java/org/apache/hadoop/mapred/YARNRunner.java

@@ -51,7 +51,6 @@ import org.apache.hadoop.mapreduce.TaskType;
 import org.apache.hadoop.mapreduce.TypeConverter;
 import org.apache.hadoop.mapreduce.protocol.ClientProtocol;
 import org.apache.hadoop.mapreduce.security.token.delegation.DelegationTokenIdentifier;
-import org.apache.hadoop.mapreduce.v2.MRConstants;
 import org.apache.hadoop.mapreduce.v2.jobhistory.JobHistoryUtils;
 import org.apache.hadoop.mapreduce.v2.util.MRApps;
 import org.apache.hadoop.security.Credentials;
@@ -60,6 +59,7 @@ import org.apache.hadoop.security.authorize.AccessControlList;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.yarn.YarnException;
 import org.apache.hadoop.yarn.api.ApplicationConstants;
+import org.apache.hadoop.yarn.api.ApplicationConstants.Environment;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.ApplicationReport;
 import org.apache.hadoop.yarn.api.records.ApplicationState;
@@ -210,7 +210,7 @@ public class YARNRunner implements ClientProtocol {
 
     // Upload only in security mode: TODO
     Path applicationTokensFile =
-        new Path(jobSubmitDir, MRConstants.APPLICATION_TOKENS_FILE);
+        new Path(jobSubmitDir, MRJobConfig.APPLICATION_TOKENS_FILE);
     try {
       ts.writeTokenStorageFile(applicationTokensFile, conf);
     } catch (IOException e) {
@@ -226,7 +226,9 @@ public class YARNRunner implements ClientProtocol {
     
     ApplicationReport appMaster = resMgrDelegate
         .getApplicationReport(applicationId);
-    String diagnostics = (appMaster == null ? "application report is null" : appMaster.getDiagnostics());
+    String diagnostics = 
+        (appMaster == null ? 
+            "application report is null" : appMaster.getDiagnostics());
     if (appMaster == null || appMaster.getState() == ApplicationState.FAILED 
         || appMaster.getState() == ApplicationState.KILLED) {
       throw new IOException("Failed to run job : " + 
@@ -263,7 +265,7 @@ public class YARNRunner implements ClientProtocol {
     Map<String, LocalResource> localResources =
         new HashMap<String, LocalResource>();
     
-    Path jobConfPath = new Path(jobSubmitDir, MRConstants.JOB_CONF_FILE);
+    Path jobConfPath = new Path(jobSubmitDir, MRJobConfig.JOB_CONF_FILE);
     
     URL yarnUrlForJobSubmitDir = ConverterUtils
         .getYarnUrlFromPath(defaultFileContext.getDefaultFileSystem()
@@ -272,13 +274,13 @@ public class YARNRunner implements ClientProtocol {
     LOG.debug("Creating setup context, jobSubmitDir url is "
         + yarnUrlForJobSubmitDir);
 
-    localResources.put(MRConstants.JOB_CONF_FILE,
+    localResources.put(MRJobConfig.JOB_CONF_FILE,
         createApplicationResource(defaultFileContext,
             jobConfPath));
     if (jobConf.get(MRJobConfig.JAR) != null) {
-      localResources.put(MRConstants.JOB_JAR,
+      localResources.put(MRJobConfig.JOB_JAR,
           createApplicationResource(defaultFileContext,
-              new Path(jobSubmitDir, MRConstants.JOB_JAR)));
+              new Path(jobSubmitDir, MRJobConfig.JOB_JAR)));
     } else {
       // Job jar may be null. For e.g, for pipes, the job jar is the hadoop
       // mapreduce jar itself which is already on the classpath.
@@ -287,10 +289,12 @@ public class YARNRunner implements ClientProtocol {
     }
     
     // TODO gross hack
-    for (String s : new String[] { "job.split", "job.splitmetainfo",
-        MRConstants.APPLICATION_TOKENS_FILE }) {
+    for (String s : new String[] { 
+        MRJobConfig.JOB_SPLIT, 
+        MRJobConfig.JOB_SPLIT_METAINFO,
+        MRJobConfig.APPLICATION_TOKENS_FILE }) {
       localResources.put(
-          MRConstants.JOB_SUBMIT_DIR + "/" + s,
+          MRJobConfig.JOB_SUBMIT_DIR + "/" + s,
           createApplicationResource(defaultFileContext, 
               new Path(jobSubmitDir, s)));
     }
@@ -304,9 +308,8 @@ public class YARNRunner implements ClientProtocol {
     }
 
     // Setup the command to run the AM
-    String javaHome = "$JAVA_HOME";
     Vector<CharSequence> vargs = new Vector<CharSequence>(8);
-    vargs.add(javaHome + "/bin/java");
+    vargs.add(Environment.JAVA_HOME.$() + "/bin/java");
     vargs.add("-Dhadoop.root.logger="
         + conf.get(MRJobConfig.MR_AM_LOG_OPTS,
             MRJobConfig.DEFAULT_MR_AM_LOG_OPTS) + ",console");
@@ -314,12 +317,15 @@ public class YARNRunner implements ClientProtocol {
     vargs.add(conf.get(MRJobConfig.MR_AM_COMMAND_OPTS,
         MRJobConfig.DEFAULT_MR_AM_COMMAND_OPTS));
 
-    vargs.add("org.apache.hadoop.mapreduce.v2.app.MRAppMaster");
+    vargs.add(MRJobConfig.APPLICATION_MASTER_CLASS);
     vargs.add(String.valueOf(applicationId.getClusterTimestamp()));
     vargs.add(String.valueOf(applicationId.getId()));
     vargs.add(ApplicationConstants.AM_FAIL_COUNT_STRING);
-    vargs.add("1>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/stdout");
-    vargs.add("2>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/stderr");
+    vargs.add("1>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + 
+        Path.SEPARATOR + ApplicationConstants.STDOUT);
+    vargs.add("2>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + 
+        Path.SEPARATOR + ApplicationConstants.STDERR);
+
 
     Vector<String> vargsFinal = new Vector<String>(8);
     // Final commmand
@@ -332,15 +338,13 @@ public class YARNRunner implements ClientProtocol {
     LOG.info("Command to launch container for ApplicationMaster is : "
         + mergedCommand);
     
-    // Setup the environment - Add { job jar, MR app jar } to classpath.
+    // Setup the CLASSPATH in environment 
+    // i.e. add { job jar, CWD, Hadoop jars} to classpath.
     Map<String, String> environment = new HashMap<String, String>();
-    MRApps.setInitialClasspath(environment);
-    MRApps.addToClassPath(environment, MRConstants.JOB_JAR);
-    MRApps.addToClassPath(environment,
-        MRConstants.YARN_MAPREDUCE_APP_JAR_PATH);
-
+    MRApps.setClasspath(environment);
+    
     // Parse distributed cache
-    MRApps.setupDistributedCache(jobConf, localResources, environment);
+    MRApps.setupDistributedCache(jobConf, localResources);
 
     // Setup ContainerLaunchContext for AM container
     ContainerLaunchContext amContainer =

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

@@ -43,9 +43,15 @@ import org.apache.hadoop.yarn.service.Service;
  */
 public class MiniMRYarnCluster extends MiniYARNCluster {
 
+  public static final String HADOOP_MAPREDUCE_CLIENT_APP_JAR_NAME =
+  "hadoop-mapreduce-client-app-0.23.0-SNAPSHOT.jar";
+  
+  public static final String YARN_MAPREDUCE_APP_JAR_PATH =
+  "$YARN_HOME/modules/" + HADOOP_MAPREDUCE_CLIENT_APP_JAR_NAME;
+
   public static final String APPJAR =
     "../hadoop-mapreduce-client-app/target/"
-        + MRConstants.HADOOP_MAPREDUCE_CLIENT_APP_JAR_NAME;
+        + HADOOP_MAPREDUCE_CLIENT_APP_JAR_NAME;
 
   private static final Log LOG = LogFactory.getLog(MiniMRYarnCluster.class);
   private JobHistoryServer historyServer;

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

@@ -402,7 +402,7 @@ public class TestMRJobs {
       // both should be reachable via the class loader.
       Assert.assertNotNull(cl.getResource("distributed.jar.inside2"));
       Assert.assertNotNull(cl.getResource("distributed.jar.inside3"));
-      Assert.assertNull(cl.getResource("distributed.jar.inside4"));
+      Assert.assertNotNull(cl.getResource("distributed.jar.inside4"));
 
       // Check that the symlink for the renaming was created in the cwd;
       File symlinkFile = new File("distributed.first.symlink");

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/api/ApplicationConstants.java

@@ -46,4 +46,117 @@ public interface ApplicationConstants {
   public static final String LOCAL_DIR_ENV = "YARN_LOCAL_DIRS";
 
   public static final String LOG_DIR_EXPANSION_VAR = "<LOG_DIR>";
+
+  public static final String STDERR = "stderr";
+
+  public static final String STDOUT = "stdout";
+  
+  /**
+   * Classpath for typical applications.
+   */
+  public static final String[] APPLICATION_CLASSPATH =
+      new String[] {
+        "$HADOOP_CONF_DIR",
+        "$HADOOP_COMMON_HOME/share/hadoop/common/*",
+        "$HADOOP_COMMON_HOME/share/hadoop/common/lib/*",
+        "$HADOOP_HDFS_HOME/share/hadoop/hdfs/*",
+        "$HADOOP_HDFS_HOME/share/hadoop/hdfs/lib/*",
+        "$YARN_HOME/modules/*",
+        "$YARN_HOME/lib/*"
+      };
+  
+  /**
+   * Environment for Applications.
+   * 
+   * Some of the environment variables for applications are <em>final</em> 
+   * i.e. they cannot be modified by the applications.
+   */
+  public enum Environment {
+    /**
+     * $USER
+     * Final, non-modifiable.
+     */
+    USER("USER"),
+    
+    /**
+     * $LOGNAME
+     * Final, non-modifiable.
+     */
+    LOGNAME("LOGNAME"),
+    
+    /**
+     * $HOME
+     * Final, non-modifiable.
+     */
+    HOME("HOME"),
+    
+    /**
+     * $PWD
+     * Final, non-modifiable.
+     */
+    PWD("PWD"),
+    
+    /**
+     * $PATH
+     */
+    PATH("PATH"),
+    
+    /**
+     * $SHELL
+     */
+    SHELL("SHELL"),
+    
+    /**
+     * $JAVA_HOME
+     */
+    JAVA_HOME("JAVA_HOME"),
+    
+    /**
+     * $CLASSPATH
+     */
+    CLASSPATH("CLASSPATH"),
+    
+    /**
+     * $LD_LIBRARY_PATH
+     */
+    LD_LIBRARY_PATH("LD_LIBRARY_PATH"),
+    
+    /**
+     * $HADOOP_CONF_DIR
+     * Final, non-modifiable.
+     */
+    HADOOP_CONF_DIR("HADOOP_CONF_DIR"),
+    
+    /**
+     * $HADOOP_COMMON_HOME
+     */
+    HADOOP_COMMON_HOME("HADOOP_COMMON_HOME"),
+    
+    /**
+     * $HADOOP_HDFS_HOME
+     */
+    HADOOP_HDFS_HOME("HADOOP_HDFS_HOME"),
+    
+    /**
+     * $YARN_HOME
+     */
+    YARN_HOME("YARN_HOME");
+
+    private final String variable;
+    private Environment(String variable) {
+      this.variable = variable;
+    }
+    
+    public String key() {
+      return variable;
+    }
+    
+    public String toString() {
+      return variable;
+    }
+    
+    public String $() {
+      return "$" + variable;
+    }
+  }
 }

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java

@@ -357,6 +357,12 @@ public class YarnConfiguration extends Configuration {
   public static final String NM_AUX_SERVICE_FMT =
     NM_PREFIX + "aux-services.%s.class";
 
+  public static final String NM_USER_HOME_DIR =
+      NM_PREFIX + "user-home-dir";
+
+  public static final String DEFAULT_NM_USER_HOME_DIR= "/home/";
+
+
   public static final int INVALID_CONTAINER_EXIT_STATUS = -1000;
   public static final int ABORTED_CONTAINER_EXIT_STATUS = -100;
   

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/DefaultContainerExecutor.java

@@ -133,8 +133,10 @@ public class DefaultContainerExecutor extends ContainerExecutor {
       String[] command = 
           new String[] { "bash", "-c", launchDst.toUri().getPath().toString() };
       LOG.info("launchContainer: " + Arrays.toString(command));
-      shExec = new ShellCommandExecutor(command,
-          new File(containerWorkDir.toUri().getPath()));
+      shExec = new ShellCommandExecutor(
+          command,
+          new File(containerWorkDir.toUri().getPath()), 
+          container.getLaunchContext().getEnvironment());      // sanitized env
       launchCommandObjs.put(containerId, shExec);
       shExec.execute();
     } catch (IOException e) {

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/LinuxContainerExecutor.java

@@ -161,7 +161,11 @@ public class LinuxContainerExecutor extends ContainerExecutor {
                     nmPrivateCotainerScriptPath.toUri().getPath().toString(),
                     nmPrivateTokensPath.toUri().getPath().toString()));
     String[] commandArray = command.toArray(new String[command.size()]);
-    ShellCommandExecutor shExec = new ShellCommandExecutor(commandArray);
+    ShellCommandExecutor shExec = 
+        new ShellCommandExecutor(
+            commandArray,
+            null,                                              // NM's cwd
+            container.getLaunchContext().getEnvironment());    // sanitized env
     launchCommandObjs.put(containerId, shExec);
     // DEBUG
     LOG.info("launchContainer: " + Arrays.toString(commandArray));

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/launcher/ContainerLaunch.java

@@ -44,6 +44,7 @@ import org.apache.hadoop.security.Credentials;
 import org.apache.hadoop.util.Shell;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.yarn.api.ApplicationConstants;
+import org.apache.hadoop.yarn.api.ApplicationConstants.Environment;
 import org.apache.hadoop.yarn.api.records.ContainerLaunchContext;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.event.Dispatcher;
@@ -89,7 +90,6 @@ public class ContainerLaunch implements Callable<Integer> {
     final Map<Path,String> localResources = container.getLocalizedResources();
     String containerIdStr = ConverterUtils.toString(container.getContainerID());
     final String user = launchContext.getUser();
-    final Map<String,String> env = launchContext.getEnvironment();
     final List<String> command = launchContext.getCommands();
     int ret = -1;
 
@@ -109,16 +109,16 @@ public class ContainerLaunch implements Callable<Integer> {
       }
       launchContext.setCommands(newCmds);
 
-      Map<String, String> envs = launchContext.getEnvironment();
-      Map<String, String> newEnvs = new HashMap<String, String>(envs.size());
-      for (Entry<String, String> entry : envs.entrySet()) {
-        newEnvs.put(
-            entry.getKey(),
-            entry.getValue().replace(
+      Map<String, String> environment = launchContext.getEnvironment();
+      // Make a copy of env to iterate & do variable expansion
+      for (Entry<String, String> entry : environment.entrySet()) {
+        String value = entry.getValue();
+        entry.setValue(
+            value.replace(
                 ApplicationConstants.LOG_DIR_EXPANSION_VAR,
-                containerLogDir.toUri().getPath()));
+                containerLogDir.toUri().getPath())
+            );
       }
-      launchContext.setEnvironment(newEnvs);
       // /////////////////////////// End of variable expansion
 
       FileContext lfs = FileContext.getLocalFSFileContext();
@@ -164,11 +164,18 @@ public class ContainerLaunch implements Callable<Integer> {
               EnumSet.of(CREATE, OVERWRITE));
 
         // Set the token location too.
-        env.put(ApplicationConstants.CONTAINER_TOKEN_FILE_ENV_NAME, new Path(
-            containerWorkDir, FINAL_CONTAINER_TOKENS_FILE).toUri().getPath());
+        environment.put(
+            ApplicationConstants.CONTAINER_TOKEN_FILE_ENV_NAME, 
+            new Path(containerWorkDir, 
+                FINAL_CONTAINER_TOKENS_FILE).toUri().getPath());
 
-        writeLaunchEnv(containerScriptOutStream, env, localResources,
-            launchContext.getCommands(), appDirs);
+        // Sanitize the container's environment
+        sanitizeEnv(environment, containerWorkDir, appDirs);
+        
+        // Write out the environment
+        writeLaunchEnv(containerScriptOutStream, environment, localResources,
+            launchContext.getCommands());
+        
         // /////////// End of writing out container-script
 
         // /////////// Write out the container-tokens in the nmPrivate space.
@@ -275,19 +282,71 @@ public class ContainerLaunch implements Callable<Integer> {
   
   }
 
+  private static void putEnvIfNotNull(
+      Map<String, String> environment, String variable, String value) {
+    if (value != null) {
+      environment.put(variable, value);
+    }
+  }
+  
+  private static void putEnvIfAbsent(
+      Map<String, String> environment, String variable) {
+    if (environment.get(variable) == null) {
+      putEnvIfNotNull(environment, variable, System.getenv(variable));
+    }
+  }
+  
+  public void sanitizeEnv(Map<String, String> environment, 
+      Path pwd, List<Path> appDirs) {
+    /**
+     * Non-modifiable environment variables
+     */
+    
+    putEnvIfNotNull(environment, Environment.USER.name(), container.getUser());
+    
+    putEnvIfNotNull(environment, 
+        Environment.LOGNAME.name(),container.getUser());
+    
+    putEnvIfNotNull(environment, 
+        Environment.HOME.name(),
+        conf.get(
+            YarnConfiguration.NM_USER_HOME_DIR, 
+            YarnConfiguration.DEFAULT_NM_USER_HOME_DIR
+            )
+        );
+    
+    putEnvIfNotNull(environment, Environment.PWD.name(), pwd.toString());
+    
+    putEnvIfNotNull(environment, 
+        Environment.HADOOP_CONF_DIR.name(), 
+        System.getenv(Environment.HADOOP_CONF_DIR.name())
+        );
+    
+    putEnvIfNotNull(environment, 
+        ApplicationConstants.LOCAL_DIR_ENV, 
+        StringUtils.join(",", appDirs)
+        );
+
+    if (!Shell.WINDOWS) {
+      environment.put("JVM_PID", "$$");
+    }
+
+    /**
+     * Modifiable environment variables
+     */
+    
+    putEnvIfAbsent(environment, Environment.JAVA_HOME.name());
+    putEnvIfAbsent(environment, Environment.HADOOP_COMMON_HOME.name());
+    putEnvIfAbsent(environment, Environment.HADOOP_HDFS_HOME.name());
+    putEnvIfAbsent(environment, Environment.YARN_HOME.name());
+
+  }
+  
   private static void writeLaunchEnv(OutputStream out,
       Map<String,String> environment, Map<Path,String> resources,
-      List<String> command, List<Path> appDirs)
+      List<String> command)
       throws IOException {
     ShellScriptBuilder sb = new ShellScriptBuilder();
-    if (System.getenv("YARN_HOME") != null) {
-      // TODO: Get from whitelist.
-      sb.env("YARN_HOME", System.getenv("YARN_HOME"));
-    }
-    sb.env(ApplicationConstants.LOCAL_DIR_ENV, StringUtils.join(",", appDirs));
-    if (!Shell.WINDOWS) {
-      sb.env("JVM_PID", "$$");
-    }
     if (environment != null) {
       for (Map.Entry<String,String> env : environment.entrySet()) {
         sb.env(env.getKey().toString(), env.getValue().toString());