HDFS-8435. Support CreateFlag in WebHDFS. Contributed by Jakob Homan

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/CreateFlag.java

@@ -53,7 +53,7 @@ import org.apache.hadoop.classification.InterfaceStability;
  * partial block.</li>
  * </ol>
  * 
- * Following combination is not valid and will result in 
+ * Following combinations are not valid and will result in
  * {@link HadoopIllegalArgumentException}:
  * <ol>
  * <li> APPEND|OVERWRITE</li>

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/WebHdfsFileSystem.java

@@ -40,6 +40,7 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.BlockLocation;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
 import org.apache.hadoop.fs.ContentSummary;
+import org.apache.hadoop.fs.CreateFlag;
 import org.apache.hadoop.fs.DelegationTokenRenewer;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FSDataOutputStream;
@@ -1175,6 +1176,25 @@ public class WebHdfsFileSystem extends FileSystem
     ).run();
   }
 
+  @Override
+  @SuppressWarnings("deprecation")
+  public FSDataOutputStream createNonRecursive(final Path f,
+      final FsPermission permission, final EnumSet<CreateFlag> flag,
+      final int bufferSize, final short replication, final long blockSize,
+      final Progressable progress) throws IOException {
+    statistics.incrementWriteOps(1);
+
+    final HttpOpParam.Op op = PutOpParam.Op.CREATE;
+    return new FsPathOutputStreamRunner(op, f, bufferSize,
+        new PermissionParam(applyUMask(permission)),
+        new CreateFlagParam(flag),
+        new CreateParentParam(false),
+        new BufferSizeParam(bufferSize),
+        new ReplicationParam(replication),
+        new BlockSizeParam(blockSize)
+    ).run();
+  }
+
   @Override
   public FSDataOutputStream append(final Path f, final int bufferSize,
       final Progressable progress) throws IOException {

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/resources/CreateFlagParam.java

@@ -0,0 +1,48 @@
+/*
+ * 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.web.resources;
+
+import org.apache.hadoop.fs.CreateFlag;
+
+import java.util.EnumSet;
+
+/**
+ * CreateFlag enum.
+ */
+public class CreateFlagParam extends EnumSetParam<CreateFlag> {
+  public static final String NAME = "createflag";
+
+  public static final String DEFAULT = "";
+
+  private static final Domain<CreateFlag> DOMAIN = new Domain<CreateFlag>(
+      NAME, CreateFlag.class);
+
+  public CreateFlagParam(final EnumSet<CreateFlag> createFlags) {
+    super(DOMAIN, createFlags);
+  }
+
+  public CreateFlagParam(final String str) {
+    super(DOMAIN, DOMAIN.parse(str));
+  }
+
+  @Override
+  public String getName() {
+    return NAME;
+  }
+}

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/resources/CreateParentParam.java

@@ -22,7 +22,7 @@ public class CreateParentParam extends BooleanParam {
   /** Parameter name. */
   public static final String NAME = "createparent";
   /** Default parameter value. */
-  public static final String DEFAULT = FALSE;
+  public static final String DEFAULT = TRUE;
 
   private static final Domain DOMAIN = new Domain(NAME);
 

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -461,6 +461,8 @@ Release 2.8.0 - UNRELEASED
     HDFS-8278. When computing max-size-to-move in Balancer, count only the
     storage with remaining >= default block size.  (szetszwo)
 
+    HDFS-8435. Support CreateFlag in WebHDFS. (Jakob Homan via cdouglas)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/webhdfs/ParameterParser.java

@@ -20,11 +20,14 @@ package org.apache.hadoop.hdfs.server.datanode.web.webhdfs;
 import io.netty.handler.codec.http.QueryStringDecoder;
 import org.apache.commons.io.Charsets;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.CreateFlag;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.HAUtilClient;
 import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
 import org.apache.hadoop.hdfs.web.resources.BlockSizeParam;
 import org.apache.hadoop.hdfs.web.resources.BufferSizeParam;
+import org.apache.hadoop.hdfs.web.resources.CreateFlagParam;
+import org.apache.hadoop.hdfs.web.resources.CreateParentParam;
 import org.apache.hadoop.hdfs.web.resources.DelegationParam;
 import org.apache.hadoop.hdfs.web.resources.DoAsParam;
 import org.apache.hadoop.hdfs.web.resources.HttpOpParam;
@@ -41,6 +44,7 @@ import org.apache.hadoop.security.token.Token;
 import java.io.IOException;
 import java.net.URI;
 import java.nio.charset.Charset;
+import java.util.EnumSet;
 import java.util.List;
 import java.util.Map;
 
@@ -122,6 +126,16 @@ class ParameterParser {
     return token;
   }
 
+  public boolean createParent() {
+    return new CreateParentParam(param(CreateParentParam.NAME)).getValue();
+  }
+
+  public EnumSet<CreateFlag> createFlag() {
+    String cf = decodeComponent(param(CreateFlagParam.NAME), Charsets.UTF_8);
+
+    return new CreateFlagParam(cf).getValue();
+  }
+
   Configuration conf() {
     return conf;
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/webhdfs/WebHdfsHandler.java

@@ -59,6 +59,7 @@ import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CreateFlag;
 import org.apache.hadoop.fs.MD5MD5CRC32FileChecksum;
+import org.apache.hadoop.fs.ParentNotDirectoryException;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.client.HdfsDataInputStream;
@@ -84,6 +85,9 @@ public class WebHdfsHandler extends SimpleChannelInboundHandler<HttpRequest> {
   public static final String APPLICATION_JSON_UTF8 =
       "application/json; charset=utf-8";
 
+  public static final EnumSet<CreateFlag> EMPTY_CREATE_FLAG =
+      EnumSet.noneOf(CreateFlag.class);
+
   private final Configuration conf;
   private final Configuration confForCreate;
 
@@ -155,15 +159,24 @@ public class WebHdfsHandler extends SimpleChannelInboundHandler<HttpRequest> {
     final short replication = params.replication();
     final long blockSize = params.blockSize();
     final FsPermission permission = params.permission();
+    final boolean createParent = params.createParent();
 
-    EnumSet<CreateFlag> flags = params.overwrite() ?
-      EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE)
-        : EnumSet.of(CreateFlag.CREATE);
+    EnumSet<CreateFlag> flags = params.createFlag();
+    if (flags.equals(EMPTY_CREATE_FLAG)) {
+      flags = params.overwrite() ?
+          EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE)
+          : EnumSet.of(CreateFlag.CREATE);
+    } else {
+      if(params.overwrite()) {
+        flags.add(CreateFlag.OVERWRITE);
+      }
+    }
 
     final DFSClient dfsClient = newDfsClient(nnId, confForCreate);
     OutputStream out = dfsClient.createWrappedOutputStream(dfsClient.create(
-      path, permission, flags, replication,
-      blockSize, null, bufferSize, null), null);
+        path, permission, flags, createParent, replication, blockSize, null,
+        bufferSize, null), null);
+
     DefaultHttpResponse resp = new DefaultHttpResponse(HTTP_1_1, CREATED);
 
     final URI uri = new URI(HDFS_URI_SCHEME, nnId, path, null, null);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/web/resources/NamenodeWebHdfsMethods.java

@@ -356,13 +356,15 @@ public class NamenodeWebHdfsMethods {
       @QueryParam(OldSnapshotNameParam.NAME) @DefaultValue(OldSnapshotNameParam.DEFAULT)
           final OldSnapshotNameParam oldSnapshotName,
       @QueryParam(ExcludeDatanodesParam.NAME) @DefaultValue(ExcludeDatanodesParam.DEFAULT)
-          final ExcludeDatanodesParam excludeDatanodes
+          final ExcludeDatanodesParam excludeDatanodes,
+      @QueryParam(CreateFlagParam.NAME) @DefaultValue(CreateFlagParam.DEFAULT)
+          final CreateFlagParam createFlagParam
       ) throws IOException, InterruptedException {
     return put(ugi, delegation, username, doAsUser, ROOT, op, destination,
         owner, group, permission, overwrite, bufferSize, replication,
         blockSize, modificationTime, accessTime, renameOptions, createParent,
         delegationTokenArgument, aclPermission, xattrName, xattrValue,
-        xattrSetFlag, snapshotName, oldSnapshotName, excludeDatanodes);
+        xattrSetFlag, snapshotName, oldSnapshotName, excludeDatanodes, createFlagParam);
   }
 
   /** Handle HTTP PUT request. */
@@ -420,14 +422,16 @@ public class NamenodeWebHdfsMethods {
       @QueryParam(OldSnapshotNameParam.NAME) @DefaultValue(OldSnapshotNameParam.DEFAULT)
           final OldSnapshotNameParam oldSnapshotName,
       @QueryParam(ExcludeDatanodesParam.NAME) @DefaultValue(ExcludeDatanodesParam.DEFAULT)
-          final ExcludeDatanodesParam excludeDatanodes
+          final ExcludeDatanodesParam excludeDatanodes,
+      @QueryParam(CreateFlagParam.NAME) @DefaultValue(CreateFlagParam.DEFAULT)
+          final CreateFlagParam createFlagParam
       ) throws IOException, InterruptedException {
 
     init(ugi, delegation, username, doAsUser, path, op, destination, owner,
         group, permission, overwrite, bufferSize, replication, blockSize,
         modificationTime, accessTime, renameOptions, delegationTokenArgument,
         aclPermission, xattrName, xattrValue, xattrSetFlag, snapshotName,
-        oldSnapshotName, excludeDatanodes);
+        oldSnapshotName, excludeDatanodes, createFlagParam);
 
     return ugi.doAs(new PrivilegedExceptionAction<Response>() {
       @Override
@@ -438,7 +442,8 @@ public class NamenodeWebHdfsMethods {
               permission, overwrite, bufferSize, replication, blockSize,
               modificationTime, accessTime, renameOptions, createParent,
               delegationTokenArgument, aclPermission, xattrName, xattrValue,
-              xattrSetFlag, snapshotName, oldSnapshotName, excludeDatanodes);
+              xattrSetFlag, snapshotName, oldSnapshotName, excludeDatanodes,
+              createFlagParam);
         } finally {
           reset();
         }
@@ -472,7 +477,8 @@ public class NamenodeWebHdfsMethods {
       final XAttrSetFlagParam xattrSetFlag,
       final SnapshotNameParam snapshotName,
       final OldSnapshotNameParam oldSnapshotName,
-      final ExcludeDatanodesParam exclDatanodes
+      final ExcludeDatanodesParam exclDatanodes,
+      final CreateFlagParam createFlagParam
       ) throws IOException, URISyntaxException {
 
     final Configuration conf = (Configuration)context.getAttribute(JspHelper.CURRENT_CONF);
@@ -485,7 +491,7 @@ public class NamenodeWebHdfsMethods {
       final URI uri = redirectURI(namenode, ugi, delegation, username,
           doAsUser, fullpath, op.getValue(), -1L, blockSize.getValue(conf),
           exclDatanodes.getValue(), permission, overwrite, bufferSize,
-          replication, blockSize);
+          replication, blockSize, createParent, createFlagParam);
       return Response.temporaryRedirect(uri).type(MediaType.APPLICATION_OCTET_STREAM).build();
     } 
     case MKDIRS:

hadoop-hdfs-project/hadoop-hdfs/src/site/markdown/WebHDFS.md

@@ -97,6 +97,7 @@ WebHDFS REST API
         * [Access Time](#Access_Time)
         * [Block Size](#Block_Size)
         * [Buffer Size](#Buffer_Size)
+        * [Create Flag](#Create_Flag)
         * [Create Parent](#Create_Parent)
         * [Delegation](#Delegation)
         * [Destination](#Destination)
@@ -1633,14 +1634,30 @@ See also: [`CREATE`](#Create_and_Write_to_a_File)
 
 See also: [`CREATE`](#Create_and_Write_to_a_File), [`APPEND`](#Append_to_a_File), [`OPEN`](#Open_and_Read_a_File)
 
+### Create Flag
+
+| Name | `createflag` |
+|:---- |:---- |
+| Description | Enum of possible flags to process while creating a file |
+| Type | enumerated strings |
+| Default Value | \<empty\> |
+| Valid Values | Legal combinations of create, overwrite, append and sync_block |
+| Syntax | See note below |
+
+The following combinations are not valid:
+* append,create
+* create,append,overwrite
+
+See also: [`CREATE`](#Create_and_Write_to_a_File)
+
 ### Create Parent
 
 | Name | `createparent` |
 |:---- |:---- |
 | Description | If the parent directories do not exist, should they be created? |
 | Type | boolean |
-| Default Value | false |
-| Valid Values | true |
+| Default Value | true |
+| Valid Values | true, false |
 | Syntax | true |
 
 See also: [`CREATESYMLINK`](#Create_a_Symbolic_Link)

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFileCreation.java

@@ -33,6 +33,7 @@ import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_REPLICATION_KEY;
 import static org.apache.hadoop.test.MetricsAsserts.assertCounter;
 import static org.apache.hadoop.test.MetricsAsserts.getMetrics;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.junit.Assume.assumeTrue;
@@ -794,93 +795,94 @@ public class TestFileCreation {
     }
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
     FileSystem fs = cluster.getFileSystem();
-    final Path path = new Path("/" + Time.now()
-        + "-testFileCreationNonRecursive");
-    FSDataOutputStream out = null;
 
     try {
-      IOException expectedException = null;
-      final String nonExistDir = "/non-exist-" + Time.now();
-
-      fs.delete(new Path(nonExistDir), true);
-      EnumSet<CreateFlag> createFlag = EnumSet.of(CreateFlag.CREATE);
-      // Create a new file in root dir, should succeed
-      out = createNonRecursive(fs, path, 1, createFlag);
-      out.close();
-      // Create a file when parent dir exists as file, should fail
-      try {
-        createNonRecursive(fs, new Path(path, "Create"), 1, createFlag);
-      } catch (IOException e) {
-        expectedException = e;
-      }
-      assertTrue("Create a file when parent directory exists as a file"
-          + " should throw ParentNotDirectoryException ",
-          expectedException != null
-              && expectedException instanceof ParentNotDirectoryException);
-      fs.delete(path, true);
-      // Create a file in a non-exist directory, should fail
-      final Path path2 = new Path(nonExistDir + "/testCreateNonRecursive");
-      expectedException = null;
-      try {
-        createNonRecursive(fs, path2, 1, createFlag);
-      } catch (IOException e) {
-        expectedException = e;
-      }
-      assertTrue("Create a file in a non-exist dir using"
-          + " createNonRecursive() should throw FileNotFoundException ",
-          expectedException != null
-              && expectedException instanceof FileNotFoundException);
-
-      EnumSet<CreateFlag> overwriteFlag = 
-        EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE);
-      // Overwrite a file in root dir, should succeed
-      out = createNonRecursive(fs, path, 1, overwriteFlag);
-      out.close();
-      // Overwrite a file when parent dir exists as file, should fail
-      expectedException = null;
-      try {
-        createNonRecursive(fs, new Path(path, "Overwrite"), 1, overwriteFlag);
-      } catch (IOException e) {
-        expectedException = e;
-      }
-      assertTrue("Overwrite a file when parent directory exists as a file"
-          + " should throw ParentNotDirectoryException ",
-          expectedException != null
-              && expectedException instanceof ParentNotDirectoryException);
-      fs.delete(path, true);
-      // Overwrite a file in a non-exist directory, should fail
-      final Path path3 = new Path(nonExistDir + "/testOverwriteNonRecursive");
-      expectedException = null;
-      try {
-        createNonRecursive(fs, path3, 1, overwriteFlag);
-      } catch (IOException e) {
-        expectedException = e;
-      }
-      assertTrue("Overwrite a file in a non-exist dir using"
-          + " createNonRecursive() should throw FileNotFoundException ",
-          expectedException != null
-              && expectedException instanceof FileNotFoundException);
+      testFileCreationNonRecursive(fs);
     } finally {
       fs.close();
       cluster.shutdown();
     }
   }
 
-  // creates a file using DistributedFileSystem.createNonRecursive()
-  static FSDataOutputStream createNonRecursive(FileSystem fs, Path name,
+  // Worker method for testing non-recursive. Extracted to allow other
+  // FileSystem implementations to re-use the tests
+  public static void testFileCreationNonRecursive(FileSystem fs) throws IOException {
+    final Path path = new Path("/" + Time.now()
+        + "-testFileCreationNonRecursive");
+    FSDataOutputStream out = null;
+    IOException expectedException = null;
+    final String nonExistDir = "/non-exist-" + Time.now();
+
+    fs.delete(new Path(nonExistDir), true);
+    EnumSet<CreateFlag> createFlag = EnumSet.of(CreateFlag.CREATE);
+    // Create a new file in root dir, should succeed
+    assertNull(createNonRecursive(fs, path, 1, createFlag));
+
+    // Create a file when parent dir exists as file, should fail
+    expectedException = createNonRecursive(fs, new Path(path, "Create"), 1, createFlag);
+
+    assertTrue("Create a file when parent directory exists as a file"
+        + " should throw ParentNotDirectoryException ",
+        expectedException != null
+            && expectedException instanceof ParentNotDirectoryException);
+    fs.delete(path, true);
+    // Create a file in a non-exist directory, should fail
+    final Path path2 = new Path(nonExistDir + "/testCreateNonRecursive");
+    expectedException =  createNonRecursive(fs, path2, 1, createFlag);
+
+    assertTrue("Create a file in a non-exist dir using"
+        + " createNonRecursive() should throw FileNotFoundException ",
+        expectedException != null
+            && expectedException instanceof FileNotFoundException);
+
+    EnumSet<CreateFlag> overwriteFlag =
+      EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE);
+    // Overwrite a file in root dir, should succeed
+    assertNull(createNonRecursive(fs, path, 1, overwriteFlag));
+
+    // Overwrite a file when parent dir exists as file, should fail
+    expectedException = createNonRecursive(fs, new Path(path, "Overwrite"), 1, overwriteFlag);
+
+    assertTrue("Overwrite a file when parent directory exists as a file"
+        + " should throw ParentNotDirectoryException ",
+        expectedException != null
+            && expectedException instanceof ParentNotDirectoryException);
+    fs.delete(path, true);
+
+    // Overwrite a file in a non-exist directory, should fail
+    final Path path3 = new Path(nonExistDir + "/testOverwriteNonRecursive");
+    expectedException = createNonRecursive(fs, path3, 1, overwriteFlag);
+
+    assertTrue("Overwrite a file in a non-exist dir using"
+        + " createNonRecursive() should throw FileNotFoundException ",
+        expectedException != null
+            && expectedException instanceof FileNotFoundException);
+  }
+
+  // Attempts to create and close a file using FileSystem.createNonRecursive(),
+  // catching and returning an exception if one occurs or null
+  // if the operation is successful.
+  @SuppressWarnings("deprecation")
+  static IOException createNonRecursive(FileSystem fs, Path name,
       int repl, EnumSet<CreateFlag> flag) throws IOException {
-    System.out.println("createNonRecursive: Created " + name + " with " + repl
-        + " replica.");
-    FSDataOutputStream stm = ((DistributedFileSystem) fs).createNonRecursive(
-        name, FsPermission.getDefault(), flag, fs.getConf().getInt(
-            CommonConfigurationKeys.IO_FILE_BUFFER_SIZE_KEY, 4096), (short) repl,  blockSize, null);
-    return stm;
+    try {
+      System.out.println("createNonRecursive: Attempting to create " + name +
+          " with " + repl + " replica.");
+      int bufferSize = fs.getConf()
+          .getInt(CommonConfigurationKeys.IO_FILE_BUFFER_SIZE_KEY, 4096);
+      FSDataOutputStream stm = fs.createNonRecursive(name,
+          FsPermission.getDefault(), flag, bufferSize, (short) repl,  blockSize,
+          null);
+      stm.close();
+    } catch (IOException e) {
+      return e;
+    }
+    return null;
   }
-  
 
-/**
- * Test that file data becomes available before file is closed.
- */
+  /**
+   * Test that file data becomes available before file is closed.
+  */
   @Test
   public void testFileCreationSimulated() throws IOException {
     simulatedStorage = true;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/web/TestWebHDFS.java

@@ -51,6 +51,7 @@ import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.TestDFSClientRetries;
+import org.apache.hadoop.hdfs.TestFileCreation;
 import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.hdfs.server.namenode.snapshot.SnapshotTestHelper;
@@ -430,6 +431,30 @@ public class TestWebHDFS {
     }
   }
 
+  @Test
+  public void testWebHdfsCreateNonRecursive() throws IOException, URISyntaxException {
+    MiniDFSCluster cluster = null;
+    final Configuration conf = WebHdfsTestUtil.createConf();
+    WebHdfsFileSystem webHdfs = null;
+
+    try {
+      cluster = new MiniDFSCluster.Builder(conf).build();
+      cluster.waitActive();
+
+      webHdfs = WebHdfsTestUtil.getWebHdfsFileSystem(conf, WebHdfsConstants.WEBHDFS_SCHEME);
+
+      TestFileCreation.testFileCreationNonRecursive(webHdfs);
+
+    } finally {
+      if(webHdfs != null) {
+       webHdfs.close();
+      }
+
+      if(cluster != null) {
+        cluster.shutdown();
+      }
+    }
+  }
   /**
    * Test snapshot rename through WebHdfs
    */