hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestLease.java - hadoop - Git at Google

 /**
  * 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.hdfs;

 import static org.mockito.Matchers.anyBoolean;
 import static org.mockito.Matchers.anyString;
 import static org.mockito.Matchers.anyShort;
 import static org.mockito.Matchers.anyLong;
 import static org.mockito.Matchers.anyObject;
 import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.spy;

 import java.io.DataOutputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.security.PrivilegedExceptionAction;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.crypto.CryptoProtocolVersion;
 import org.apache.hadoop.fs.CreateFlag;
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Options;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.client.impl.LeaseRenewer;
 import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.server.namenode.NameNodeAdapter;
 import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
 import org.apache.hadoop.io.EnumSetWritable;
 import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.token.SecretManager.InvalidToken;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.apache.hadoop.util.Time;
 import org.junit.Assert;
 import org.junit.Test;
 import org.mockito.Mockito;

 public class TestLease {
   static boolean hasLease(MiniDFSCluster cluster, Path src) {
     return NameNodeAdapter.getLeaseForPath(cluster.getNameNode(),
             src.toString()) != null;
   }

   static int leaseCount(MiniDFSCluster cluster) {
     return NameNodeAdapter.getLeaseManager(cluster.getNamesystem()).countLease();
   }

   static final String dirString = "/test/lease";
   final Path dir = new Path(dirString);
   static final Log LOG = LogFactory.getLog(TestLease.class);
   final Configuration conf = new HdfsConfiguration();

   @Test
   public void testLeaseAbort() throws Exception {
     MiniDFSCluster cluster =
         new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
     try {
       cluster.waitActive();
       NamenodeProtocols preSpyNN = cluster.getNameNodeRpc();
       NamenodeProtocols spyNN = spy(preSpyNN);

       DFSClient dfs = new DFSClient(null, spyNN, conf, null);
       byte[] buf = new byte[1024];

       FSDataOutputStream c_out = createFsOut(dfs, dirString + "c");
       c_out.write(buf, 0, 1024);
       c_out.close();

       DFSInputStream c_in = dfs.open(dirString + "c");
       FSDataOutputStream d_out = createFsOut(dfs, dirString + "d");

       // stub the renew method.
       doThrow(new RemoteException(InvalidToken.class.getName(),
           "Your token is worthless")).when(spyNN).renewLease(anyString());

       // We don't need to wait the lease renewer thread to act.
       // call renewLease() manually.
       // make it look like the soft limit has been exceeded.
       LeaseRenewer originalRenewer = dfs.getLeaseRenewer();
       dfs.lastLeaseRenewal = Time.monotonicNow() -
           HdfsConstants.LEASE_SOFTLIMIT_PERIOD - 1000;
       try {
         dfs.renewLease();
       } catch (IOException e) {}

       // Things should continue to work it passes hard limit without
       // renewing.
       try {
         d_out.write(buf, 0, 1024);
         LOG.info("Write worked beyond the soft limit as expected.");
       } catch (IOException e) {
         Assert.fail("Write failed.");
       }

       // make it look like the hard limit has been exceeded.
       dfs.lastLeaseRenewal = Time.monotonicNow()
       - HdfsConstants.LEASE_HARDLIMIT_PERIOD - 1000;
       dfs.renewLease();

       // this should not work.
       try {
         d_out.write(buf, 0, 1024);
         d_out.close();
         Assert.fail("Write did not fail even after the fatal lease renewal failure");
       } catch (IOException e) {
         LOG.info("Write failed as expected. ", e);
       }

       // If aborted, the renewer should be empty. (no reference to clients)
       Thread.sleep(1000);
       Assert.assertTrue(originalRenewer.isEmpty());

       // unstub
       doNothing().when(spyNN).renewLease(anyString());

       // existing input streams should work
       try {
         int num = c_in.read(buf, 0, 1);
         if (num != 1) {
           Assert.fail("Failed to read 1 byte");
         }
         c_in.close();
       } catch (IOException e) {
          LOG.error("Read failed with ", e);
          Assert.fail("Read after lease renewal failure failed");
       }

       // new file writes should work.
       try {
         c_out = createFsOut(dfs, dirString + "c");
         c_out.write(buf, 0, 1024);
         c_out.close();
       } catch (IOException e) {
         LOG.error("Write failed with ", e);
         Assert.fail("Write failed");
       }
     } finally {
       cluster.shutdown();
     }
   }

   @Test
   public void testLeaseAfterRename() throws Exception {
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
     try {
       Path p = new Path("/test-file");
       Path d = new Path("/test-d");
       Path d2 = new Path("/test-d-other");

       // open a file to get a lease
       FileSystem fs = cluster.getFileSystem();
       FSDataOutputStream out = fs.create(p);
       out.writeBytes("something");
       //out.hsync();
       Assert.assertTrue(hasLease(cluster, p));
       Assert.assertEquals(1, leaseCount(cluster));

       // just to ensure first fs doesn't have any logic to twiddle leases
       DistributedFileSystem fs2 = (DistributedFileSystem) FileSystem.newInstance(fs.getUri(), fs.getConf());

       // rename the file into an existing dir
       LOG.info("DMS: rename file into dir");
       Path pRenamed = new Path(d, p.getName());
       fs2.mkdirs(d);
       fs2.rename(p, pRenamed);
       Assert.assertFalse(p+" exists", fs2.exists(p));
       Assert.assertTrue(pRenamed+" not found", fs2.exists(pRenamed));
       Assert.assertFalse("has lease for "+p, hasLease(cluster, p));
       Assert.assertTrue("no lease for "+pRenamed, hasLease(cluster, pRenamed));
       Assert.assertEquals(1, leaseCount(cluster));

       // rename the parent dir to a new non-existent dir
       LOG.info("DMS: rename parent dir");
       Path pRenamedAgain = new Path(d2, pRenamed.getName());
       fs2.rename(d, d2);
       // src gone
       Assert.assertFalse(d+" exists", fs2.exists(d));
       Assert.assertFalse("has lease for "+pRenamed, hasLease(cluster, pRenamed));
       // dst checks
       Assert.assertTrue(d2+" not found", fs2.exists(d2));
       Assert.assertTrue(pRenamedAgain+" not found", fs2.exists(pRenamedAgain));
       Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
       Assert.assertEquals(1, leaseCount(cluster));

       // rename the parent dir to existing dir
       // NOTE: rename w/o options moves paths into existing dir
       LOG.info("DMS: rename parent again");
       pRenamed = pRenamedAgain;
       pRenamedAgain = new Path(new Path(d, d2.getName()), p.getName());
       fs2.mkdirs(d);
       fs2.rename(d2, d);
       // src gone
       Assert.assertFalse(d2+" exists", fs2.exists(d2));
       Assert.assertFalse("no lease for "+pRenamed, hasLease(cluster, pRenamed));
       // dst checks
       Assert.assertTrue(d+" not found", fs2.exists(d));
       Assert.assertTrue(pRenamedAgain +" not found", fs2.exists(pRenamedAgain));
       Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
       Assert.assertEquals(1, leaseCount(cluster));

       // rename with opts to non-existent dir
       pRenamed = pRenamedAgain;
       pRenamedAgain = new Path(d2, p.getName());
       fs2.rename(pRenamed.getParent(), d2, Options.Rename.OVERWRITE);
       // src gone
       Assert.assertFalse(pRenamed.getParent() +" not found", fs2.exists(pRenamed.getParent()));
       Assert.assertFalse("has lease for "+pRenamed, hasLease(cluster, pRenamed));
       // dst checks
       Assert.assertTrue(d2+" not found", fs2.exists(d2));
       Assert.assertTrue(pRenamedAgain+" not found", fs2.exists(pRenamedAgain));
       Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
       Assert.assertEquals(1, leaseCount(cluster));

       // rename with opts to existing dir
       // NOTE: rename with options will not move paths into the existing dir
       pRenamed = pRenamedAgain;
       pRenamedAgain = new Path(d, p.getName());
       fs2.rename(pRenamed.getParent(), d, Options.Rename.OVERWRITE);
       // src gone
       Assert.assertFalse(pRenamed.getParent() +" not found", fs2.exists(pRenamed.getParent()));
       Assert.assertFalse("has lease for "+pRenamed, hasLease(cluster, pRenamed));
       // dst checks
       Assert.assertTrue(d+" not found", fs2.exists(d));
       Assert.assertTrue(pRenamedAgain+" not found", fs2.exists(pRenamedAgain));
       Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
       Assert.assertEquals(1, leaseCount(cluster));
       out.close();
     } finally {
       cluster.shutdown();
     }
   }

   /**
    * Test that we can open up a file for write, move it to another location,
    * and then create a new file in the previous location, without causing any
    * lease conflicts.  This is possible because we now use unique inode IDs
    * to identify files to the NameNode.
    */
   @Test
   public void testLeaseAfterRenameAndRecreate() throws Exception {
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
     try {
       final Path path1 = new Path("/test-file");
       final String contents1 = "contents1";
       final Path path2 = new Path("/test-file-new-location");
       final String contents2 = "contents2";

       // open a file to get a lease
       FileSystem fs = cluster.getFileSystem();
       FSDataOutputStream out1 = fs.create(path1);
       out1.writeBytes(contents1);
       Assert.assertTrue(hasLease(cluster, path1));
       Assert.assertEquals(1, leaseCount(cluster));

       DistributedFileSystem fs2 = (DistributedFileSystem)
           FileSystem.newInstance(fs.getUri(), fs.getConf());
       fs2.rename(path1, path2);

       FSDataOutputStream out2 = fs2.create(path1);
       out2.writeBytes(contents2);
       out2.close();

       // The first file should still be open and valid
       Assert.assertTrue(hasLease(cluster, path2));
       out1.close();

       // Contents should be as expected
       DistributedFileSystem fs3 = (DistributedFileSystem)
           FileSystem.newInstance(fs.getUri(), fs.getConf());
       Assert.assertEquals(contents1, DFSTestUtil.readFile(fs3, path2));
       Assert.assertEquals(contents2, DFSTestUtil.readFile(fs3, path1));
     } finally {
       cluster.shutdown();
     }
   }

   @Test
   public void testLease() throws Exception {
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
     try {
       FileSystem fs = cluster.getFileSystem();
       Assert.assertTrue(fs.mkdirs(dir));

       Path a = new Path(dir, "a");
       Path b = new Path(dir, "b");

       DataOutputStream a_out = fs.create(a);
       a_out.writeBytes("something");

       Assert.assertTrue(hasLease(cluster, a));
       Assert.assertTrue(!hasLease(cluster, b));

       DataOutputStream b_out = fs.create(b);
       b_out.writeBytes("something");

       Assert.assertTrue(hasLease(cluster, a));
       Assert.assertTrue(hasLease(cluster, b));

       a_out.close();
       b_out.close();

       Assert.assertTrue(!hasLease(cluster, a));
       Assert.assertTrue(!hasLease(cluster, b));

       Path fileA = new Path(dir, "fileA");
       FSDataOutputStream fileA_out = fs.create(fileA);
       fileA_out.writeBytes("something");
       Assert.assertTrue("Failed to get the lease!", hasLease(cluster, fileA));

       fs.delete(dir, true);
       try {
         fileA_out.hflush();
         Assert.fail("Should validate file existence!");
       } catch (FileNotFoundException e) {
         // expected
         GenericTestUtils.assertExceptionContains("File does not exist", e);
       }
     } finally {
       if (cluster != null) {cluster.shutdown();}
     }
   }

   @SuppressWarnings("unchecked")
   @Test
   public void testFactory() throws Exception {
     final String[] groups = new String[]{"supergroup"};
     final UserGroupInformation[] ugi = new UserGroupInformation[3];
     for(int i = 0; i < ugi.length; i++) {
       ugi[i] = UserGroupInformation.createUserForTesting("user" + i, groups);
     }

     Mockito.doReturn(
         new HdfsFileStatus(0, false, 1, 1024, 0, 0, new FsPermission(
             (short) 777), "owner", "group", new byte[0], new byte[0],
             1010, 0, null, (byte) 0)).when(mcp).getFileInfo(anyString());
     Mockito
         .doReturn(
             new HdfsFileStatus(0, false, 1, 1024, 0, 0, new FsPermission(
                 (short) 777), "owner", "group", new byte[0], new byte[0],
                 1010, 0, null, (byte) 0))
         .when(mcp)
         .create(anyString(), (FsPermission) anyObject(), anyString(),
             (EnumSetWritable<CreateFlag>) anyObject(), anyBoolean(),
             anyShort(), anyLong(), (CryptoProtocolVersion[]) anyObject());

     final Configuration conf = new Configuration();
     final DFSClient c1 = createDFSClientAs(ugi[0], conf);
     FSDataOutputStream out1 = createFsOut(c1, "/out1");
     final DFSClient c2 = createDFSClientAs(ugi[0], conf);
     FSDataOutputStream out2 = createFsOut(c2, "/out2");
     Assert.assertEquals(c1.getLeaseRenewer(), c2.getLeaseRenewer());
     final DFSClient c3 = createDFSClientAs(ugi[1], conf);
     FSDataOutputStream out3 = createFsOut(c3, "/out3");
     Assert.assertTrue(c1.getLeaseRenewer() != c3.getLeaseRenewer());
     final DFSClient c4 = createDFSClientAs(ugi[1], conf);
     FSDataOutputStream out4 = createFsOut(c4, "/out4");
     Assert.assertEquals(c3.getLeaseRenewer(), c4.getLeaseRenewer());
     final DFSClient c5 = createDFSClientAs(ugi[2], conf);
     FSDataOutputStream out5 = createFsOut(c5, "/out5");
     Assert.assertTrue(c1.getLeaseRenewer() != c5.getLeaseRenewer());
     Assert.assertTrue(c3.getLeaseRenewer() != c5.getLeaseRenewer());
   }

   private FSDataOutputStream createFsOut(DFSClient dfs, String path)
       throws IOException {
     return new FSDataOutputStream(dfs.create(path, true), null);
   }

   static final ClientProtocol mcp = Mockito.mock(ClientProtocol.class);
   static public DFSClient createDFSClientAs(UserGroupInformation ugi,
       final Configuration conf) throws Exception {
     return ugi.doAs(new PrivilegedExceptionAction<DFSClient>() {
       @Override
       public DFSClient run() throws Exception {
         return new DFSClient(null, mcp, conf, null);
       }
     });
   }
 }
	/**
	* 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.hdfs;

	import static org.mockito.Matchers.anyBoolean;
	import static org.mockito.Matchers.anyString;
	import static org.mockito.Matchers.anyShort;
	import static org.mockito.Matchers.anyLong;
	import static org.mockito.Matchers.anyObject;
	import static org.mockito.Mockito.doNothing;
	import static org.mockito.Mockito.doThrow;
	import static org.mockito.Mockito.spy;

	import java.io.DataOutputStream;
	import java.io.FileNotFoundException;
	import java.io.IOException;
	import java.security.PrivilegedExceptionAction;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;
	import org.apache.hadoop.conf.Configuration;
	import org.apache.hadoop.crypto.CryptoProtocolVersion;
	import org.apache.hadoop.fs.CreateFlag;
	import org.apache.hadoop.fs.FSDataOutputStream;
	import org.apache.hadoop.fs.FileSystem;
	import org.apache.hadoop.fs.Options;
	import org.apache.hadoop.fs.Path;
	import org.apache.hadoop.fs.permission.FsPermission;
	import org.apache.hadoop.hdfs.client.impl.LeaseRenewer;
	import org.apache.hadoop.hdfs.protocol.ClientProtocol;
	import org.apache.hadoop.hdfs.protocol.HdfsConstants;
	import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
	import org.apache.hadoop.hdfs.server.namenode.NameNodeAdapter;
	import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
	import org.apache.hadoop.io.EnumSetWritable;
	import org.apache.hadoop.ipc.RemoteException;
	import org.apache.hadoop.security.UserGroupInformation;
	import org.apache.hadoop.security.token.SecretManager.InvalidToken;
	import org.apache.hadoop.test.GenericTestUtils;
	import org.apache.hadoop.util.Time;
	import org.junit.Assert;
	import org.junit.Test;
	import org.mockito.Mockito;

	public class TestLease {
	static boolean hasLease(MiniDFSCluster cluster, Path src) {
	return NameNodeAdapter.getLeaseForPath(cluster.getNameNode(),
	src.toString()) != null;
	}

	static int leaseCount(MiniDFSCluster cluster) {
	return NameNodeAdapter.getLeaseManager(cluster.getNamesystem()).countLease();
	}

	static final String dirString = "/test/lease";
	final Path dir = new Path(dirString);
	static final Log LOG = LogFactory.getLog(TestLease.class);
	final Configuration conf = new HdfsConfiguration();

	@Test
	public void testLeaseAbort() throws Exception {
	MiniDFSCluster cluster =
	new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
	try {
	cluster.waitActive();
	NamenodeProtocols preSpyNN = cluster.getNameNodeRpc();
	NamenodeProtocols spyNN = spy(preSpyNN);

	DFSClient dfs = new DFSClient(null, spyNN, conf, null);
	byte[] buf = new byte[1024];

	FSDataOutputStream c_out = createFsOut(dfs, dirString + "c");
	c_out.write(buf, 0, 1024);
	c_out.close();

	DFSInputStream c_in = dfs.open(dirString + "c");
	FSDataOutputStream d_out = createFsOut(dfs, dirString + "d");

	// stub the renew method.
	doThrow(new RemoteException(InvalidToken.class.getName(),
	"Your token is worthless")).when(spyNN).renewLease(anyString());

	// We don't need to wait the lease renewer thread to act.
	// call renewLease() manually.
	// make it look like the soft limit has been exceeded.
	LeaseRenewer originalRenewer = dfs.getLeaseRenewer();
	dfs.lastLeaseRenewal = Time.monotonicNow() -
	HdfsConstants.LEASE_SOFTLIMIT_PERIOD - 1000;
	try {
	dfs.renewLease();
	} catch (IOException e) {}

	// Things should continue to work it passes hard limit without
	// renewing.
	try {
	d_out.write(buf, 0, 1024);
	LOG.info("Write worked beyond the soft limit as expected.");
	} catch (IOException e) {
	Assert.fail("Write failed.");
	}

	// make it look like the hard limit has been exceeded.
	dfs.lastLeaseRenewal = Time.monotonicNow()
	- HdfsConstants.LEASE_HARDLIMIT_PERIOD - 1000;
	dfs.renewLease();

	// this should not work.
	try {
	d_out.write(buf, 0, 1024);
	d_out.close();
	Assert.fail("Write did not fail even after the fatal lease renewal failure");
	} catch (IOException e) {
	LOG.info("Write failed as expected. ", e);
	}

	// If aborted, the renewer should be empty. (no reference to clients)
	Thread.sleep(1000);
	Assert.assertTrue(originalRenewer.isEmpty());

	// unstub
	doNothing().when(spyNN).renewLease(anyString());

	// existing input streams should work
	try {
	int num = c_in.read(buf, 0, 1);
	if (num != 1) {
	Assert.fail("Failed to read 1 byte");
	}
	c_in.close();
	} catch (IOException e) {
	LOG.error("Read failed with ", e);
	Assert.fail("Read after lease renewal failure failed");
	}

	// new file writes should work.
	try {
	c_out = createFsOut(dfs, dirString + "c");
	c_out.write(buf, 0, 1024);
	c_out.close();
	} catch (IOException e) {
	LOG.error("Write failed with ", e);
	Assert.fail("Write failed");
	}
	} finally {
	cluster.shutdown();
	}
	}

	@Test
	public void testLeaseAfterRename() throws Exception {
	MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
	try {
	Path p = new Path("/test-file");
	Path d = new Path("/test-d");
	Path d2 = new Path("/test-d-other");

	// open a file to get a lease
	FileSystem fs = cluster.getFileSystem();
	FSDataOutputStream out = fs.create(p);
	out.writeBytes("something");
	//out.hsync();
	Assert.assertTrue(hasLease(cluster, p));
	Assert.assertEquals(1, leaseCount(cluster));

	// just to ensure first fs doesn't have any logic to twiddle leases
	DistributedFileSystem fs2 = (DistributedFileSystem) FileSystem.newInstance(fs.getUri(), fs.getConf());

	// rename the file into an existing dir
	LOG.info("DMS: rename file into dir");
	Path pRenamed = new Path(d, p.getName());
	fs2.mkdirs(d);
	fs2.rename(p, pRenamed);
	Assert.assertFalse(p+" exists", fs2.exists(p));
	Assert.assertTrue(pRenamed+" not found", fs2.exists(pRenamed));
	Assert.assertFalse("has lease for "+p, hasLease(cluster, p));
	Assert.assertTrue("no lease for "+pRenamed, hasLease(cluster, pRenamed));
	Assert.assertEquals(1, leaseCount(cluster));

	// rename the parent dir to a new non-existent dir
	LOG.info("DMS: rename parent dir");
	Path pRenamedAgain = new Path(d2, pRenamed.getName());
	fs2.rename(d, d2);
	// src gone
	Assert.assertFalse(d+" exists", fs2.exists(d));
	Assert.assertFalse("has lease for "+pRenamed, hasLease(cluster, pRenamed));
	// dst checks
	Assert.assertTrue(d2+" not found", fs2.exists(d2));
	Assert.assertTrue(pRenamedAgain+" not found", fs2.exists(pRenamedAgain));
	Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
	Assert.assertEquals(1, leaseCount(cluster));

	// rename the parent dir to existing dir
	// NOTE: rename w/o options moves paths into existing dir
	LOG.info("DMS: rename parent again");
	pRenamed = pRenamedAgain;
	pRenamedAgain = new Path(new Path(d, d2.getName()), p.getName());
	fs2.mkdirs(d);
	fs2.rename(d2, d);
	// src gone
	Assert.assertFalse(d2+" exists", fs2.exists(d2));
	Assert.assertFalse("no lease for "+pRenamed, hasLease(cluster, pRenamed));
	// dst checks
	Assert.assertTrue(d+" not found", fs2.exists(d));
	Assert.assertTrue(pRenamedAgain +" not found", fs2.exists(pRenamedAgain));
	Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
	Assert.assertEquals(1, leaseCount(cluster));

	// rename with opts to non-existent dir
	pRenamed = pRenamedAgain;
	pRenamedAgain = new Path(d2, p.getName());
	fs2.rename(pRenamed.getParent(), d2, Options.Rename.OVERWRITE);
	// src gone
	Assert.assertFalse(pRenamed.getParent() +" not found", fs2.exists(pRenamed.getParent()));
	Assert.assertFalse("has lease for "+pRenamed, hasLease(cluster, pRenamed));
	// dst checks
	Assert.assertTrue(d2+" not found", fs2.exists(d2));
	Assert.assertTrue(pRenamedAgain+" not found", fs2.exists(pRenamedAgain));
	Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
	Assert.assertEquals(1, leaseCount(cluster));

	// rename with opts to existing dir
	// NOTE: rename with options will not move paths into the existing dir
	pRenamed = pRenamedAgain;
	pRenamedAgain = new Path(d, p.getName());
	fs2.rename(pRenamed.getParent(), d, Options.Rename.OVERWRITE);
	// src gone
	Assert.assertFalse(pRenamed.getParent() +" not found", fs2.exists(pRenamed.getParent()));
	Assert.assertFalse("has lease for "+pRenamed, hasLease(cluster, pRenamed));
	// dst checks
	Assert.assertTrue(d+" not found", fs2.exists(d));
	Assert.assertTrue(pRenamedAgain+" not found", fs2.exists(pRenamedAgain));
	Assert.assertTrue("no lease for "+pRenamedAgain, hasLease(cluster, pRenamedAgain));
	Assert.assertEquals(1, leaseCount(cluster));
	out.close();
	} finally {
	cluster.shutdown();
	}
	}

	/**
	* Test that we can open up a file for write, move it to another location,
	* and then create a new file in the previous location, without causing any
	* lease conflicts. This is possible because we now use unique inode IDs
	* to identify files to the NameNode.
	*/
	@Test
	public void testLeaseAfterRenameAndRecreate() throws Exception {
	MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
	try {
	final Path path1 = new Path("/test-file");
	final String contents1 = "contents1";
	final Path path2 = new Path("/test-file-new-location");
	final String contents2 = "contents2";

	// open a file to get a lease
	FileSystem fs = cluster.getFileSystem();
	FSDataOutputStream out1 = fs.create(path1);
	out1.writeBytes(contents1);
	Assert.assertTrue(hasLease(cluster, path1));
	Assert.assertEquals(1, leaseCount(cluster));

	DistributedFileSystem fs2 = (DistributedFileSystem)
	FileSystem.newInstance(fs.getUri(), fs.getConf());
	fs2.rename(path1, path2);

	FSDataOutputStream out2 = fs2.create(path1);
	out2.writeBytes(contents2);
	out2.close();

	// The first file should still be open and valid
	Assert.assertTrue(hasLease(cluster, path2));
	out1.close();

	// Contents should be as expected
	DistributedFileSystem fs3 = (DistributedFileSystem)
	FileSystem.newInstance(fs.getUri(), fs.getConf());
	Assert.assertEquals(contents1, DFSTestUtil.readFile(fs3, path2));
	Assert.assertEquals(contents2, DFSTestUtil.readFile(fs3, path1));
	} finally {
	cluster.shutdown();
	}
	}

	@Test
	public void testLease() throws Exception {
	MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
	try {
	FileSystem fs = cluster.getFileSystem();
	Assert.assertTrue(fs.mkdirs(dir));

	Path a = new Path(dir, "a");
	Path b = new Path(dir, "b");

	DataOutputStream a_out = fs.create(a);
	a_out.writeBytes("something");

	Assert.assertTrue(hasLease(cluster, a));
	Assert.assertTrue(!hasLease(cluster, b));

	DataOutputStream b_out = fs.create(b);
	b_out.writeBytes("something");

	Assert.assertTrue(hasLease(cluster, a));
	Assert.assertTrue(hasLease(cluster, b));

	a_out.close();
	b_out.close();

	Assert.assertTrue(!hasLease(cluster, a));
	Assert.assertTrue(!hasLease(cluster, b));

	Path fileA = new Path(dir, "fileA");
	FSDataOutputStream fileA_out = fs.create(fileA);
	fileA_out.writeBytes("something");
	Assert.assertTrue("Failed to get the lease!", hasLease(cluster, fileA));

	fs.delete(dir, true);
	try {
	fileA_out.hflush();
	Assert.fail("Should validate file existence!");
	} catch (FileNotFoundException e) {
	// expected
	GenericTestUtils.assertExceptionContains("File does not exist", e);
	}
	} finally {
	if (cluster != null) {cluster.shutdown();}
	}
	}

	@SuppressWarnings("unchecked")
	@Test
	public void testFactory() throws Exception {
	final String[] groups = new String[]{"supergroup"};
	final UserGroupInformation[] ugi = new UserGroupInformation[3];
	for(int i = 0; i < ugi.length; i++) {
	ugi[i] = UserGroupInformation.createUserForTesting("user" + i, groups);
	}

	Mockito.doReturn(
	new HdfsFileStatus(0, false, 1, 1024, 0, 0, new FsPermission(
	(short) 777), "owner", "group", new byte[0], new byte[0],
	1010, 0, null, (byte) 0)).when(mcp).getFileInfo(anyString());
	Mockito
	.doReturn(
	new HdfsFileStatus(0, false, 1, 1024, 0, 0, new FsPermission(
	(short) 777), "owner", "group", new byte[0], new byte[0],
	1010, 0, null, (byte) 0))
	.when(mcp)
	.create(anyString(), (FsPermission) anyObject(), anyString(),
	(EnumSetWritable<CreateFlag>) anyObject(), anyBoolean(),
	anyShort(), anyLong(), (CryptoProtocolVersion[]) anyObject());

	final Configuration conf = new Configuration();
	final DFSClient c1 = createDFSClientAs(ugi[0], conf);
	FSDataOutputStream out1 = createFsOut(c1, "/out1");
	final DFSClient c2 = createDFSClientAs(ugi[0], conf);
	FSDataOutputStream out2 = createFsOut(c2, "/out2");
	Assert.assertEquals(c1.getLeaseRenewer(), c2.getLeaseRenewer());
	final DFSClient c3 = createDFSClientAs(ugi[1], conf);
	FSDataOutputStream out3 = createFsOut(c3, "/out3");
	Assert.assertTrue(c1.getLeaseRenewer() != c3.getLeaseRenewer());
	final DFSClient c4 = createDFSClientAs(ugi[1], conf);
	FSDataOutputStream out4 = createFsOut(c4, "/out4");
	Assert.assertEquals(c3.getLeaseRenewer(), c4.getLeaseRenewer());
	final DFSClient c5 = createDFSClientAs(ugi[2], conf);
	FSDataOutputStream out5 = createFsOut(c5, "/out5");
	Assert.assertTrue(c1.getLeaseRenewer() != c5.getLeaseRenewer());
	Assert.assertTrue(c3.getLeaseRenewer() != c5.getLeaseRenewer());
	}

	private FSDataOutputStream createFsOut(DFSClient dfs, String path)
	throws IOException {
	return new FSDataOutputStream(dfs.create(path, true), null);
	}

	static final ClientProtocol mcp = Mockito.mock(ClientProtocol.class);
	static public DFSClient createDFSClientAs(UserGroupInformation ugi,
	final Configuration conf) throws Exception {
	return ugi.doAs(new PrivilegedExceptionAction<DFSClient>() {
	@Override
	public DFSClient run() throws Exception {
	return new DFSClient(null, mcp, conf, null);
	}
	});
	}
	}