HDFS-14064. WEBHDFS: Support Enable/Disable EC Policy. Contributed by Ayush Saxena.

(cherry picked from commit 15d8f592b51d08a658e88c6a7a7596e0edf5793b)
(cherry picked from commit 7e10dd03b5)

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

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

@@ -1308,6 +1308,16 @@ public class WebHdfsFileSystem extends FileSystem
     new FsPathRunner(op, p).run();
   }
 
+  public void enableECPolicy(String policyName) throws IOException {
+    final HttpOpParam.Op op = PutOpParam.Op.ENABLEECPOLICY;
+    new FsPathRunner(op, null, new ECPolicyParam(policyName)).run();
+  }
+
+  public void disableECPolicy(String policyName) throws IOException {
+    final HttpOpParam.Op op = PutOpParam.Op.DISABLEECPOLICY;
+    new FsPathRunner(op, null, new ECPolicyParam(policyName)).run();
+  }
+
   @Override
   public Path createSnapshot(final Path path, final String snapshotName)
       throws IOException {

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

@@ -0,0 +1,42 @@
+/**
+ * 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;
+
+/** policy parameter. */
+public class ECPolicyParam extends StringParam {
+  /** Parameter name. */
+  public static final String NAME = "ecpolicy";
+  /** Default parameter value. */
+  public static final String DEFAULT = "";
+
+  private static final Domain DOMAIN = new Domain(NAME, null);
+
+  /**
+   * Constructor.
+   *
+   * @param str a string representation of the parameter value.
+   */
+  public ECPolicyParam(final String str) {
+    super(DOMAIN, str == null || str.equals(DEFAULT) ? null : str);
+  }
+
+  @Override
+  public String getName() {
+    return NAME;
+  }
+}

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

@@ -46,6 +46,9 @@ public class PutOpParam extends HttpOpParam<PutOpParam.Op> {
     SETXATTR(false, HttpURLConnection.HTTP_OK),
     REMOVEXATTR(false, HttpURLConnection.HTTP_OK),
 
+    ENABLEECPOLICY(false, HttpURLConnection.HTTP_OK),
+    DISABLEECPOLICY(false, HttpURLConnection.HTTP_OK),
+
     ALLOWSNAPSHOT(false, HttpURLConnection.HTTP_OK),
     DISALLOWSNAPSHOT(false, HttpURLConnection.HTTP_OK),
     CREATESNAPSHOT(false, HttpURLConnection.HTTP_OK),

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterWebHdfsMethods.java

@@ -54,6 +54,7 @@ import org.apache.hadoop.hdfs.web.resources.CreateParentParam;
 import org.apache.hadoop.hdfs.web.resources.DelegationParam;
 import org.apache.hadoop.hdfs.web.resources.DestinationParam;
 import org.apache.hadoop.hdfs.web.resources.DoAsParam;
+import org.apache.hadoop.hdfs.web.resources.ECPolicyParam;
 import org.apache.hadoop.hdfs.web.resources.ExcludeDatanodesParam;
 import org.apache.hadoop.hdfs.web.resources.FsActionParam;
 import org.apache.hadoop.hdfs.web.resources.GetOpParam;
@@ -215,7 +216,8 @@ public class RouterWebHdfsMethods extends NamenodeWebHdfsMethods {
       final ExcludeDatanodesParam exclDatanodes,
       final CreateFlagParam createFlagParam,
       final NoRedirectParam noredirectParam,
-      final StoragePolicyParam policyName
+      final StoragePolicyParam policyName,
+      final ECPolicyParam ecpolicy
   ) throws IOException, URISyntaxException {
 
     switch(op.getValue()) {
@@ -252,6 +254,8 @@ public class RouterWebHdfsMethods extends NamenodeWebHdfsMethods {
     case RENAMESNAPSHOT:
     case DISALLOWSNAPSHOT:
     case SETSTORAGEPOLICY:
+    case ENABLEECPOLICY:
+    case DISABLEECPOLICY:
     {
       // Whitelist operations that can handled by NamenodeWebHdfsMethods
       return super.put(ugi, delegation, username, doAsUser, fullpath, op,
@@ -260,7 +264,7 @@ public class RouterWebHdfsMethods extends NamenodeWebHdfsMethods {
           accessTime, renameOptions, createParent, delegationTokenArgument,
           aclPermission, xattrName, xattrValue, xattrSetFlag, snapshotName,
           oldSnapshotName, exclDatanodes, createFlagParam, noredirectParam,
-          policyName);
+          policyName, ecpolicy);
     }
     default:
       throw new UnsupportedOperationException(op + " is not supported");

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

@@ -500,14 +500,16 @@ public class NamenodeWebHdfsMethods {
       @QueryParam(NoRedirectParam.NAME) @DefaultValue(NoRedirectParam.DEFAULT)
           final NoRedirectParam noredirect,
       @QueryParam(StoragePolicyParam.NAME) @DefaultValue(StoragePolicyParam
-          .DEFAULT) final StoragePolicyParam policyName
+          .DEFAULT) final StoragePolicyParam policyName,
+      @QueryParam(ECPolicyParam.NAME) @DefaultValue(ECPolicyParam
+              .DEFAULT) final ECPolicyParam ecpolicy
       ) throws IOException, InterruptedException {
     return put(ugi, delegation, username, doAsUser, ROOT, op, destination,
         owner, group, permission, unmaskedPermission, overwrite, bufferSize,
         replication, blockSize, modificationTime, accessTime, renameOptions,
         createParent, delegationTokenArgument, aclPermission, xattrName,
         xattrValue, xattrSetFlag, snapshotName, oldSnapshotName,
-        excludeDatanodes, createFlagParam, noredirect, policyName);
+        excludeDatanodes, createFlagParam, noredirect, policyName, ecpolicy);
   }
 
   /** Validate all required params. */
@@ -587,7 +589,9 @@ public class NamenodeWebHdfsMethods {
       @QueryParam(NoRedirectParam.NAME) @DefaultValue(NoRedirectParam.DEFAULT)
           final NoRedirectParam noredirect,
       @QueryParam(StoragePolicyParam.NAME) @DefaultValue(StoragePolicyParam
-          .DEFAULT) final StoragePolicyParam policyName
+          .DEFAULT) final StoragePolicyParam policyName,
+      @QueryParam(ECPolicyParam.NAME) @DefaultValue(ECPolicyParam.DEFAULT)
+      final ECPolicyParam ecpolicy
       ) throws IOException, InterruptedException {
 
     init(ugi, delegation, username, doAsUser, path, op, destination, owner,
@@ -607,7 +611,7 @@ public class NamenodeWebHdfsMethods {
               renameOptions, createParent, delegationTokenArgument,
               aclPermission, xattrName, xattrValue, xattrSetFlag,
               snapshotName, oldSnapshotName, excludeDatanodes,
-              createFlagParam, noredirect, policyName);
+              createFlagParam, noredirect, policyName, ecpolicy);
       }
     });
   }
@@ -642,7 +646,8 @@ public class NamenodeWebHdfsMethods {
       final ExcludeDatanodesParam exclDatanodes,
       final CreateFlagParam createFlagParam,
       final NoRedirectParam noredirectParam,
-      final StoragePolicyParam policyName
+      final StoragePolicyParam policyName,
+      final ECPolicyParam ecpolicy
       ) throws IOException, URISyntaxException {
     final Configuration conf = (Configuration)context.getAttribute(JspHelper.CURRENT_CONF);
     final ClientProtocol cp = getRpcClientProtocol();
@@ -803,6 +808,16 @@ public class NamenodeWebHdfsMethods {
       cp.setStoragePolicy(fullpath, policyName.getValue());
       return Response.ok().type(MediaType.APPLICATION_OCTET_STREAM).build();
     }
+    case ENABLEECPOLICY:
+      validateOpParams(op, ecpolicy);
+      cp.enableErasureCodingPolicy(ecpolicy.getValue());
+      return Response.ok().type(MediaType.APPLICATION_OCTET_STREAM).build();
+
+    case DISABLEECPOLICY:
+      validateOpParams(op, ecpolicy);
+      cp.disableErasureCodingPolicy(ecpolicy.getValue());
+      return Response.ok().type(MediaType.APPLICATION_OCTET_STREAM).build();
+
     default:
       throw new UnsupportedOperationException(op + " is not supported");
     }

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

@@ -69,6 +69,8 @@ The HTTP REST API supports the complete [FileSystem](../../api/org/apache/hadoop
     * [`SETXATTR`](#Set_XAttr) (see [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).setXAttr)
     * [`REMOVEXATTR`](#Remove_XAttr) (see [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).removeXAttr)
     * [`SETSTORAGEPOLICY`](#Set_Storage_Policy) (see [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).setStoragePolicy)
+    * [`ENABLEECPOLICY`](#Enable_EC_Policy) (see [HDFSErasureCoding](./HDFSErasureCoding.html#Administrative_commands).enablePolicy)
+    * [`DISABLEECPOLICY`](#Disable_EC_Policy) (see [HDFSErasureCoding](./HDFSErasureCoding.html#Administrative_commands).disablePolicy)
 *   HTTP POST
     * [`APPEND`](#Append_to_a_File) (see [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).append)
     * [`CONCAT`](#Concat_Files) (see [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).concat)
@@ -1316,6 +1318,37 @@ See also: [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).getXAttrs
 
 See also: [FileSystem](../../api/org/apache/hadoop/fs/FileSystem.html).listXAttrs
 
+Erasure Coding Operations
+-------------------------
+
+### Enable EC Policy
+
+* Submit a HTTP PUT request.
+
+        curl -i -X PUT "http://<HOST>:<PORT>/webhdfs/v1/?op=ENABLEECPOLICY
+                                      &ecpolicy=<policy>"
+
+    The client receives a response with zero content length:
+
+        HTTP/1.1 200 OK
+        Content-Length: 0
+
+See also: [HDFSErasureCoding](./HDFSErasureCoding.html#Administrative_commands).enablePolicy)
+
+### Disable EC Policy
+
+* Submit a HTTP PUT request.
+
+        curl -i -X PUT "http://<HOST>:<PORT>/webhdfs/v1/?op=DISABLEECPOLICY
+                                      &ecpolicy=<policy>"
+
+    The client receives a response with zero content length:
+
+        HTTP/1.1 200 OK
+        Content-Length: 0
+
+See also: [HDFSErasureCoding](./HDFSErasureCoding.html#Administrative_commands).disablePolicy)
+
 Snapshot Operations
 -------------------
 
@@ -2851,6 +2884,18 @@ See also: [Create and Write to a File](#Create_and_Write_to_a_File)
 
 See also: [`SETSTORAGEPOLICY`](#Set_Storage_Policy)
 
+### Erasure Coding Policy
+
+| Name | `ecpolicy` |
+|:---- |:---- |
+| Description | The name of the erasure coding policy. |
+| Type | String |
+| Default Value | \<empty\> |
+| Valid Values | Any valid erasure coding policy name;  |
+| Syntax | Any string. |
+
+See also: [`ENABLEECPOLICY`](#Enable_EC_Policy) or [`DISABLEECPOLICY`](#Disable_EC_Policy)
+
 ### Start After
 
 | Name | `startAfter` |

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

@@ -47,6 +47,8 @@ import java.net.URL;
 import java.nio.charset.StandardCharsets;
 import java.security.PrivilegedExceptionAction;
 import java.util.Arrays;
+import java.util.Collection;
+import java.util.Iterator;
 import java.util.Random;
 
 import com.google.common.collect.ImmutableList;
@@ -85,6 +87,7 @@ import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
 import org.apache.hadoop.hdfs.protocol.BlockStoragePolicy;
 import org.apache.hadoop.hdfs.protocol.DSQuotaExceededException;
 import org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy;
+import org.apache.hadoop.hdfs.protocol.ErasureCodingPolicyInfo;
 import org.apache.hadoop.hdfs.protocol.SystemErasureCodingPolicies;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport;
@@ -1549,6 +1552,49 @@ public class TestWebHDFS {
     }
   }
 
+  private void checkECPolicyState(Collection<ErasureCodingPolicyInfo> policies,
+      String ecpolicy, String state) {
+    Iterator<ErasureCodingPolicyInfo> itr = policies.iterator();
+    boolean found = false;
+    while (policies.iterator().hasNext()) {
+      ErasureCodingPolicyInfo policy = itr.next();
+      if (policy.getPolicy().getName().equals(ecpolicy)) {
+        found = true;
+        if (state.equals("disable")) {
+          Assert.assertTrue(policy.isDisabled());
+        } else if (state.equals("enable")) {
+          Assert.assertTrue(policy.isEnabled());
+        }
+        break;
+      }
+    }
+    Assert.assertTrue(found);
+  }
+
+  // Test For Enable/Disable EC Policy in DFS.
+  @Test
+  public void testEnableDisableECPolicy() throws Exception {
+    Configuration conf = new HdfsConfiguration();
+    try (MiniDFSCluster cluster =
+        new MiniDFSCluster.Builder(conf).numDataNodes(0).build()) {
+      cluster.waitActive();
+      final DistributedFileSystem dfs = cluster.getFileSystem();
+      final WebHdfsFileSystem webHdfs = WebHdfsTestUtil
+          .getWebHdfsFileSystem(conf, WebHdfsConstants.WEBHDFS_SCHEME);
+      String policy = "RS-10-4-1024k";
+
+      // Check for Enable EC policy via WEBHDFS.
+      dfs.disableErasureCodingPolicy(policy);
+      checkECPolicyState(dfs.getAllErasureCodingPolicies(), policy, "disable");
+      webHdfs.enableECPolicy("RS-10-4-1024k");
+      checkECPolicyState(dfs.getAllErasureCodingPolicies(), policy, "enable");
+
+      // Check for Disable EC policy via WEBHDFS.
+      webHdfs.disableECPolicy(policy);
+      checkECPolicyState(dfs.getAllErasureCodingPolicies(), policy, "disable");
+    }
+  }
+
   @Test
   public void testWebHdfsAppend() throws Exception {
     MiniDFSCluster cluster = null;

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

@@ -505,6 +505,14 @@ public class TestParam {
     Assert.assertEquals("COLD", p.getValue());
   }
 
+  @Test
+  public void testECPolicyParam() {
+    ECPolicyParam p = new ECPolicyParam(ECPolicyParam.DEFAULT);
+    Assert.assertEquals(null, p.getValue());
+    p = new ECPolicyParam("RS-6-3-1024k");
+    Assert.assertEquals("RS-6-3-1024k", p.getValue());
+  }
+
   @Test
   public void testHttpOpParams() {
     try {