From 3c373405e0bfc9ac3cca1f1bc02dbcd63e756056 Mon Sep 17 00:00:00 2001
From: Uma Maheswara Rao G <umamahesh@apache.org>
Date: Fri, 9 Mar 2012 18:48:35 +0000
Subject: [PATCH] HADOOP-8146.  FsShell commands cannot be interrupted.
 Contributed by Daryn Shar

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1298976 13f79535-47bb-0310-9956-ffa450edef68
---
 .../hadoop-common/CHANGES.txt                 |  3 ++
 .../org/apache/hadoop/fs/shell/Command.java   | 11 ++++
 .../hadoop/fs/TestFsShellReturnCode.java      | 54 +++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index 3f6d043a477..fad77d10878 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -59,6 +59,9 @@ Trunk (unreleased changes)
 
   BUG FIXES
 
+    HADOOP-8146.  FsShell commands cannot be interrupted
+    (Daryn Sharp via Uma Maheswara Rao G)
+
     HADOOP-8018.  Hudson auto test for HDFS has started throwing javadoc
     (Jon Eagles via bobby)
 
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/shell/Command.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/shell/Command.java
index b24d47e02b1..f3f32fcc309 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/shell/Command.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/shell/Command.java
@@ -19,6 +19,7 @@
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.io.InterruptedIOException;
 import java.io.PrintStream;
 import java.lang.reflect.Field;
 import java.util.ArrayList;
@@ -152,6 +153,9 @@ public int run(String...argv) {
       }
       processOptions(args);
       processRawArguments(args);
+    } catch (CommandInterruptException e) {
+      displayError("Interrupted");
+      return 130;
     } catch (IOException e) {
       displayError(e);
     }
@@ -349,6 +353,10 @@ protected void recursePath(PathData item) throws IOException {
   public void displayError(Exception e) {
     // build up a list of exceptions that occurred
     exceptions.add(e);
+    // use runtime so it rips up through the stack and exits out 
+    if (e instanceof InterruptedIOException) {
+      throw new CommandInterruptException();
+    }
     
     String errorMessage = e.getLocalizedMessage();
     if (errorMessage == null) {
@@ -454,4 +462,7 @@ private String getCommandField(String field) {
     }
     return value;
   }
+  
+  @SuppressWarnings("serial")
+  static class CommandInterruptException extends RuntimeException {}
 }
diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestFsShellReturnCode.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestFsShellReturnCode.java
index e05d00a894a..75eb9e69ee3 100644
--- a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestFsShellReturnCode.java
+++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestFsShellReturnCode.java
@@ -23,6 +23,7 @@
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.InterruptedIOException;
 import java.io.PrintStream;
 import java.util.Collections;
 import java.util.HashMap;
@@ -33,6 +34,9 @@
 import org.apache.commons.logging.LogFactory;
 import org.apache.ftpserver.command.impl.STAT;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.shell.CommandFactory;
+import org.apache.hadoop.fs.shell.FsCommand;
+import org.apache.hadoop.fs.shell.PathData;
 import org.apache.hadoop.io.IOUtils;
 import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.FS_DEFAULT_NAME_KEY;
 import org.junit.BeforeClass;
@@ -331,6 +335,33 @@ public void testInvalidDefaultFS() throws Exception {
     
   }
   
+  @Test
+  public void testInterrupt() throws Exception {
+    MyFsShell shell = new MyFsShell();
+    shell.setConf(new Configuration());
+    final Path d = new Path(TEST_ROOT_DIR, "testInterrupt");
+    final Path f1 = new Path(d, "f1");
+    final Path f2 = new Path(d, "f2");
+    assertTrue(fileSys.mkdirs(d));
+    writeFile(fileSys, f1);
+    assertTrue(fileSys.isFile(f1));
+    writeFile(fileSys, f2);
+    assertTrue(fileSys.isFile(f2));
+
+    int exitCode = shell.run(
+        new String[]{ "-testInterrupt", f1.toString(), f2.toString() });
+    // processing a file throws an interrupt, it should blow on first file
+    assertEquals(1, InterruptCommand.processed);
+    assertEquals(130, exitCode);
+    
+    exitCode = shell.run(
+        new String[]{ "-testInterrupt", d.toString() });
+    // processing a file throws an interrupt, it should blow on file
+    // after descent into dir
+    assertEquals(2, InterruptCommand.processed);
+    assertEquals(130, exitCode);
+  }
+  
   static class LocalFileSystemExtn extends LocalFileSystem {
     public LocalFileSystemExtn() {
       super(new RawLocalFileSystemExtn());
@@ -379,4 +410,27 @@ public FileStatus getFileStatus(Path p) throws IOException {
       return stat;
     }
   }
+  
+  static class MyFsShell extends FsShell {
+    protected void registerCommands(CommandFactory factory) {
+      factory.addClass(InterruptCommand.class, "-testInterrupt");
+    }
+  }
+
+  static class InterruptCommand extends FsCommand {
+    static int processed = 0;
+    InterruptCommand() {
+      processed = 0;
+      setRecursive(true);
+    }
+    @Override
+    protected void processPath(PathData item) throws IOException {
+      System.out.println("processing: "+item);
+      processed++;
+      if (item.stat.isFile()) {
+        System.out.println("throw interrupt");
+        throw new InterruptedIOException();
+      }
+    }
+  }  
 }