HDFS-2827. Cannot save namespace after renaming a directory above a file with an open lease. Contributed by Uma Maheswara Rao G

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1359836 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -63,6 +63,9 @@ Release 1.2.0 - unreleased
     MAPREDUCE-3993. Graceful handling of codec errors during decompression 
     (kkambatl via tucu)
 
+    HDFS-2827. Cannot save namespace after renaming a directory above
+    a file with an open lease. (Uma Maheswara Rao G via eli)
+ 
 Release 1.1.0 - unreleased
 
   INCOMPATIBLE CHANGES

src/hdfs/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -5464,7 +5464,12 @@ public class FSNamesystem implements FSConstants, FSNamesystemMBean,
 
     if (destinationExisted && dinfo.isDir()) {
       Path spath = new Path(src);
-      overwrite = spath.getParent().toString() + Path.SEPARATOR;
+      Path parent = spath.getParent();
+      if (isRoot(parent)) {
+        overwrite = parent.toString();
+      } else {
+        overwrite = parent.toString() + Path.SEPARATOR;
+      }
       replaceBy = dst + Path.SEPARATOR;
     } else {
       overwrite = src;
@@ -5473,7 +5478,11 @@ public class FSNamesystem implements FSConstants, FSNamesystemMBean,
 
     leaseManager.changeLease(src, dst, overwrite, replaceBy);
   }
-           
+
+  private boolean isRoot(Path path) {
+    return path.getParent() == null;
+  }
+
   /**
    * Serializes leases. 
    */

src/test/org/apache/hadoop/hdfs/server/namenode/TestSaveNamespace.java

@@ -22,8 +22,14 @@ import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.spy;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
 import java.io.File;
 import java.io.IOException;
+import java.io.OutputStream;
 
 import junit.framework.TestCase;
 
@@ -31,10 +37,14 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.fs.permission.PermissionStatus;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.protocol.FSConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory;
+import org.apache.hadoop.io.IOUtils;
 import org.mockito.invocation.InvocationOnMock;
 import org.mockito.stubbing.Answer;
 
@@ -196,6 +206,35 @@ public class TestSaveNamespace extends TestCase {
     }
   }
 
+  /**
+   * Test for save namespace should succeed when parent directory renamed with
+   * open lease and destination directory exist. 
+   * This test is a regression for HDFS-2827
+   */
+  // @Test
+  public void testSaveNamespaceWithRenamedLease() throws Exception {
+    MiniDFSCluster cluster = new MiniDFSCluster(
+        new Configuration(), 1, true, null);
+    cluster.waitActive();
+
+    DistributedFileSystem fs = (DistributedFileSystem) cluster.getFileSystem();
+    OutputStream out = null;
+    try {
+      fs.mkdirs(new Path("/test-target"));
+      out = fs.create(new Path("/test-source/foo")); // don't close
+      fs.rename(new Path("/test-source/"), new Path("/test-target/"));
+
+      fs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
+      cluster.getNameNode().saveNamespace();
+      fs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
+    } finally {
+      IOUtils.cleanup(LOG, out, fs);
+      if (cluster != null) {
+        cluster.shutdown();
+      }
+    }
+  }
+
   private void doAnEdit(FSNamesystem fsn, int id) throws IOException {
     // Make an edit
     fsn.mkdirs(