HDFS-9645. DiskBalancer: Add Query RPC. (Contributed by Anu Engineer)

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientDatanodeProtocol.java

@@ -30,6 +30,7 @@ import org.apache.hadoop.hdfs.security.token.block.BlockTokenSelector;
 import org.apache.hadoop.security.KerberosInfo;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.TokenInfo;
+import org.apache.hadoop.hdfs.server.datanode.WorkStatus;
 
 /** An client-datanode protocol for block recovery
  */
@@ -177,4 +178,9 @@ public interface ClientDatanodeProtocol {
    */
   void cancelDiskBalancePlan(String planID) throws IOException;
 
+
+  /**
+   * Gets the status of an executing diskbalancer Plan.
+   */
+  WorkStatus queryDiskBalancerPlan() throws IOException;
 }

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocolPB/ClientDatanodeProtocolTranslatorPB.java

@@ -54,7 +54,10 @@ import org.apache.hadoop.hdfs.protocol.proto.ReconfigurationProtocolProtos.Start
 import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.TriggerBlockReportRequestProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.SubmitDiskBalancerPlanRequestProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.CancelPlanRequestProto;
+import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.QueryPlanStatusRequestProto;
+import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.QueryPlanStatusResponseProto;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
+import org.apache.hadoop.hdfs.server.datanode.WorkStatus;
 import org.apache.hadoop.ipc.ProtobufHelper;
 import org.apache.hadoop.ipc.ProtobufRpcEngine;
 import org.apache.hadoop.ipc.ProtocolMetaInterface;
@@ -377,4 +380,23 @@ public class ClientDatanodeProtocolTranslatorPB implements
       throw ProtobufHelper.getRemoteException(e);
     }
   }
+
+  /**
+   * Gets the status of an executing diskbalancer Plan.
+   */
+  @Override
+  public WorkStatus queryDiskBalancerPlan() throws IOException {
+    try {
+      QueryPlanStatusRequestProto request =
+          QueryPlanStatusRequestProto.newBuilder().build();
+      QueryPlanStatusResponseProto response =
+          rpcProxy.queryDiskBalancerPlan(NULL_CONTROLLER, request);
+      return new WorkStatus(response.hasResult() ? response.getResult() : 0,
+          response.hasPlanID() ? response.getPlanID() : null,
+          response.hasStatus() ? response.getStatus() : null,
+          response.hasCurrentStatus() ? response.getCurrentStatus() : null);
+    } catch (ServiceException e) {
+      throw ProtobufHelper.getRemoteException(e);
+    }
+  }
 }

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/server/datanode/WorkStatus.java

@@ -0,0 +1,85 @@
+/*
+ * 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.server.datanode;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
+/**
+ * Helper class that reports how much work has has been done by the node.
+ */
+@InterfaceAudience.Private
+public class WorkStatus {
+  private int result;
+  private String planID;
+  private String status;
+  private String currentState;
+
+  /**
+   * Constructs a workStatus Object.
+   *
+   * @param result       - int
+   * @param planID       - Plan ID
+   * @param status       - Current Status
+   * @param currentState - Current State
+   */
+  public WorkStatus(int result, String planID, String status,
+                    String currentState) {
+    this.result = result;
+    this.planID = planID;
+    this.status = status;
+    this.currentState = currentState;
+  }
+
+  /**
+   * Returns result.
+   *
+   * @return long
+   */
+  public int getResult() {
+    return result;
+  }
+
+  /**
+   * Returns planID.
+   *
+   * @return String
+   */
+  public String getPlanID() {
+    return planID;
+  }
+
+  /**
+   * Returns Status.
+   *
+   * @return String
+   */
+  public String getStatus() {
+    return status;
+  }
+
+  /**
+   * Gets current Status.
+   *
+   * @return - Json String
+   */
+  public String getCurrentState() {
+    return currentState;
+  }
+}

hadoop-hdfs-project/hadoop-hdfs-client/src/main/proto/ClientDatanodeProtocol.proto

@@ -180,6 +180,26 @@ message CancelPlanRequestProto {
 message CancelPlanResponseProto {
 }
 
+
+/**
+ * This message allows a client to query data node to see
+ * if a disk balancer plan is executing and if so what is
+ * the status.
+ */
+message QueryPlanStatusRequestProto {
+}
+
+/**
+ * This message describes a plan if it is in progress
+ */
+message QueryPlanStatusResponseProto {
+  optional uint32 result = 1;
+  optional string status = 2;
+  optional string planID = 3;
+  optional string currentStatus = 4;
+
+}
+
 /**
  * Protocol used from client to the Datanode.
  * See the request and response for details of rpc call.
@@ -249,4 +269,10 @@ service ClientDatanodeProtocolService {
    */
   rpc cancelDiskBalancerPlan(CancelPlanRequestProto)
       returns (CancelPlanResponseProto);
+
+  /**
+   * Gets the status of an executing Plan
+   */
+  rpc queryDiskBalancerPlan(QueryPlanStatusRequestProto)
+      returns (QueryPlanStatusResponseProto);
 }

hadoop-hdfs-project/hadoop-hdfs/HDFS-1312_CHANGES.txt

@@ -19,3 +19,5 @@ HDFS-1312 Change Log
     HDFS-9595. DiskBalancer: Add cancelPlan RPC. (Anu Engineer via
     Arpit Agarwal)
 
+    HDFS-9645. DiskBalancer: Add Query RPC. (Anu Engineer via Arpit Agarwal)
+

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/ClientDatanodeProtocolServerSideTranslatorPB.java

@@ -51,9 +51,12 @@ import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.Submit
 import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.SubmitDiskBalancerPlanResponseProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.CancelPlanRequestProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.CancelPlanResponseProto;
+import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.QueryPlanStatusRequestProto;
+import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.QueryPlanStatusResponseProto;
 
 import com.google.protobuf.RpcController;
 import com.google.protobuf.ServiceException;
+import org.apache.hadoop.hdfs.server.datanode.WorkStatus;
 
 /**
  * Implementation for protobuf service that forwards requests
@@ -281,4 +284,24 @@ public class ClientDatanodeProtocolServerSideTranslatorPB implements
     }
   }
 
+  /**
+   * Gets the status of an executing Plan.
+   */
+  @Override
+  public QueryPlanStatusResponseProto queryDiskBalancerPlan(
+      RpcController controller,  QueryPlanStatusRequestProto request)
+      throws ServiceException {
+    try {
+      WorkStatus result = impl.queryDiskBalancerPlan();
+      return QueryPlanStatusResponseProto
+          .newBuilder()
+          .setResult(result.getResult())
+          .setPlanID(result.getPlanID())
+          .setStatus(result.getStatus())
+          .setCurrentStatus(result.getCurrentState())
+          .build();
+    } catch (Exception e) {
+      throw new ServiceException(e);
+    }
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -3317,4 +3317,9 @@ public class DataNode extends ReconfigurableBase
     throw new DiskbalancerException("Not Implemented", 0);
   }
 
+  @Override
+  public WorkStatus queryDiskBalancerPlan() throws IOException {
+    checkSuperuserPrivilege();
+    throw new DiskbalancerException("Not Implemented", 0);
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/diskbalancer/TestDiskBalancerRPC.java

@@ -35,6 +35,7 @@ import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
 
+import java.io.IOException;
 import java.net.URI;
 
 public class TestDiskBalancerRPC {
@@ -43,6 +44,7 @@ public class TestDiskBalancerRPC {
 
   private MiniDFSCluster cluster;
   private Configuration conf;
+
   @Before
   public void setUp() throws Exception {
     conf = new HdfsConfiguration();
@@ -113,11 +115,51 @@ public class TestDiskBalancerRPC {
 
     // Since submitDiskBalancerPlan is not implemented yet, it throws an
     // Exception, this will be modified with the actual implementation.
-    thrown.expect(DiskbalancerException.class);
-    dataNode.submitDiskBalancerPlan(planHash, planVersion, 10, plan.toJson());
-
+    try {
+      dataNode.submitDiskBalancerPlan(planHash, planVersion, 10, plan.toJson());
+    } catch (DiskbalancerException ex) {
+      // Let us ignore this for time being.
+    }
     thrown.expect(DiskbalancerException.class);
     dataNode.cancelDiskBalancePlan(planHash);
 
   }
+
+  @Test
+  public void TestQueryTestRpc() throws Exception {
+    final int dnIndex = 0;
+    cluster.restartDataNode(dnIndex);
+    cluster.waitActive();
+    ClusterConnector nameNodeConnector =
+        ConnectorFactory.getCluster(cluster.getFileSystem(0).getUri(), conf);
+
+    DiskBalancerCluster diskBalancerCluster = new DiskBalancerCluster
+        (nameNodeConnector);
+    diskBalancerCluster.readClusterInfo();
+    Assert.assertEquals(cluster.getDataNodes().size(),
+        diskBalancerCluster.getNodes().size());
+    diskBalancerCluster.setNodesToProcess(diskBalancerCluster.getNodes());
+    DiskBalancerDataNode node = diskBalancerCluster.getNodes().get(0);
+    GreedyPlanner planner = new GreedyPlanner(10.0f, node);
+    NodePlan plan = new NodePlan(node.getDataNodeName(), node.getDataNodePort
+        ());
+    planner.balanceVolumeSet(node, node.getVolumeSets().get("DISK"), plan);
+
+    final int planVersion = 0; // So far we support only one version.
+    DataNode dataNode = cluster.getDataNodes().get(dnIndex);
+    String planHash = DigestUtils.sha512Hex(plan.toJson());
+
+    // Since submitDiskBalancerPlan is not implemented yet, it throws an
+    // Exception, this will be modified with the actual implementation.
+    try {
+      dataNode.submitDiskBalancerPlan(planHash, planVersion, 10, plan.toJson());
+    } catch (DiskbalancerException ex) {
+      // Let us ignore this for time being.
+    }
+
+    // TODO : This will be fixed when we have implementation for this
+    // function in server side.
+    thrown.expect(DiskbalancerException.class);
+    dataNode.queryDiskBalancerPlan();
+  }
 }