HDDS-141. Remove PipeLine Class from SCM and move the data field in the Pipeline to ContainerInfo. Contributed by Shashikant Banerjee.

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/common/helpers/ContainerInfo.java

@@ -19,6 +19,7 @@
 package org.apache.hadoop.hdds.scm.container.common.helpers;
 
 import com.fasterxml.jackson.annotation.JsonAutoDetect;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.PropertyAccessor;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectWriter;
@@ -30,6 +31,7 @@ import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
 import org.apache.hadoop.util.Time;
 
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.Comparator;
 
 import static java.lang.Math.max;
@@ -63,6 +65,13 @@ public class ContainerInfo
   private String owner;
   private long containerID;
   private long deleteTransactionId;
+  /**
+   * Allows you to maintain private data on ContainerInfo. This is not
+   * serialized via protobuf, just allows us to maintain some private data.
+   */
+  @JsonIgnore
+  private byte[] data;
+
   ContainerInfo(
       long containerID,
       HddsProtos.LifeCycleState state,
@@ -295,6 +304,29 @@ public class ContainerInfo
     return WRITER.writeValueAsString(this);
   }
 
+  /**
+   * Returns private data that is set on this containerInfo.
+   *
+   * @return blob, the user can interpret it any way they like.
+   */
+  public byte[] getData() {
+    if (this.data != null) {
+      return Arrays.copyOf(this.data, this.data.length);
+    } else {
+      return null;
+    }
+  }
+
+  /**
+   * Set private data on ContainerInfo object.
+   *
+   * @param data -- private data.
+   */
+  public void setData(byte[] data) {
+    if (data != null) {
+      this.data = Arrays.copyOf(data, data.length);
+    }
+  }
   /**
    * Builder class for ContainerInfo.
    */

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/common/helpers/Pipeline.java

@@ -27,14 +27,14 @@ import com.fasterxml.jackson.databind.ObjectWriter;
 import com.fasterxml.jackson.databind.ser.FilterProvider;
 import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter;
 import com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider;
-import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import org.apache.hadoop.hdds.protocol.DatanodeDetails;
 import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
 
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Map;
+import java.util.TreeMap;
 import java.util.List;
 
 /**
@@ -46,7 +46,7 @@ public class Pipeline {
 
   static {
     ObjectMapper mapper = new ObjectMapper();
-    String[] ignorableFieldNames = {"data"};
+    String[] ignorableFieldNames = {"leaderID", "datanodes"};
     FilterProvider filters = new SimpleFilterProvider()
         .addFilter(PIPELINE_INFO, SimpleBeanPropertyFilter
             .serializeAllExcept(ignorableFieldNames));
@@ -57,38 +57,66 @@ public class Pipeline {
     WRITER = mapper.writer(filters);
   }
 
-  private PipelineChannel pipelineChannel;
-  /**
-   * Allows you to maintain private data on pipelines. This is not serialized
-   * via protobuf, just allows us to maintain some private data.
-   */
   @JsonIgnore
-  private byte[] data;
+  private String leaderID;
+  @JsonIgnore
+  private Map<String, DatanodeDetails> datanodes;
+  private HddsProtos.LifeCycleState lifeCycleState;
+  private HddsProtos.ReplicationType type;
+  private HddsProtos.ReplicationFactor factor;
+  private String name;
+  // TODO: change to long based id
+  //private long id;
+
   /**
    * Constructs a new pipeline data structure.
    *
-   * @param pipelineChannel - transport information for this container
+   * @param leaderID       -  Leader datanode id
+   * @param lifeCycleState  - Pipeline State
+   * @param replicationType - Replication protocol
+   * @param replicationFactor - replication count on datanodes
+   * @param name  - pipelineName
    */
-  public Pipeline(PipelineChannel pipelineChannel) {
-    this.pipelineChannel = pipelineChannel;
-    data = null;
+  public Pipeline(String leaderID, HddsProtos.LifeCycleState lifeCycleState,
+      HddsProtos.ReplicationType replicationType,
+      HddsProtos.ReplicationFactor replicationFactor, String name) {
+    this.leaderID = leaderID;
+    this.lifeCycleState = lifeCycleState;
+    this.type = replicationType;
+    this.factor = replicationFactor;
+    this.name = name;
+    datanodes = new TreeMap<>();
   }
 
   /**
    * Gets pipeline object from protobuf.
    *
-   * @param pipeline - ProtoBuf definition for the pipeline.
+   * @param pipelineProto - ProtoBuf definition for the pipeline.
    * @return Pipeline Object
    */
-  public static Pipeline getFromProtoBuf(HddsProtos.Pipeline pipeline) {
-    Preconditions.checkNotNull(pipeline);
-    PipelineChannel pipelineChannel =
-        PipelineChannel.getFromProtoBuf(pipeline.getPipelineChannel());
-    return new Pipeline(pipelineChannel);
+  public static Pipeline getFromProtoBuf(
+      HddsProtos.Pipeline pipelineProto) {
+    Preconditions.checkNotNull(pipelineProto);
+    Pipeline pipeline =
+        new Pipeline(pipelineProto.getLeaderID(),
+            pipelineProto.getState(),
+            pipelineProto.getType(),
+            pipelineProto.getFactor(),
+            pipelineProto.getName());
+
+    for (HddsProtos.DatanodeDetailsProto dataID :
+        pipelineProto.getMembersList()) {
+      pipeline.addMember(DatanodeDetails.getFromProtoBuf(dataID));
+    }
+    return pipeline;
   }
 
+  /**
+   * returns the replication count.
+   * @return Replication Factor
+   */
   public HddsProtos.ReplicationFactor getFactor() {
-    return pipelineChannel.getFactor();
+    return factor;
   }
 
   /**
@@ -98,19 +126,34 @@ public class Pipeline {
    */
   @JsonIgnore
   public DatanodeDetails getLeader() {
-    return pipelineChannel.getDatanodes().get(pipelineChannel.getLeaderID());
+    return getDatanodes().get(leaderID);
   }
 
+  public void addMember(DatanodeDetails datanodeDetails) {
+    datanodes.put(datanodeDetails.getUuid().toString(),
+        datanodeDetails);
+  }
+
+  public Map<String, DatanodeDetails> getDatanodes() {
+    return datanodes;
+  }
   /**
    * Returns the leader host.
    *
    * @return First Machine.
    */
   public String getLeaderHost() {
-    return pipelineChannel.getDatanodes()
-        .get(pipelineChannel.getLeaderID()).getHostName();
+    return getDatanodes()
+        .get(leaderID).getHostName();
   }
 
+  /**
+   *
+   * @return lead
+   */
+  public String getLeaderID() {
+    return leaderID;
+  }
   /**
    * Returns all machines that make up this pipeline.
    *
@@ -118,7 +161,7 @@ public class Pipeline {
    */
   @JsonIgnore
   public List<DatanodeDetails> getMachines() {
-    return new ArrayList<>(pipelineChannel.getDatanodes().values());
+    return new ArrayList<>(getDatanodes().values());
   }
 
   /**
@@ -128,7 +171,7 @@ public class Pipeline {
    */
   public List<String> getDatanodeHosts() {
     List<String> dataHosts = new ArrayList<>();
-    for (DatanodeDetails id : pipelineChannel.getDatanodes().values()) {
+    for (DatanodeDetails id :getDatanodes().values()) {
       dataHosts.add(id.getHostName());
     }
     return dataHosts;
@@ -143,37 +186,22 @@ public class Pipeline {
   public HddsProtos.Pipeline getProtobufMessage() {
     HddsProtos.Pipeline.Builder builder =
         HddsProtos.Pipeline.newBuilder();
-    builder.setPipelineChannel(this.pipelineChannel.getProtobufMessage());
-    return builder.build();
-  }
-
-  /**
-   * Returns private data that is set on this pipeline.
-   *
-   * @return blob, the user can interpret it any way they like.
-   */
-  public byte[] getData() {
-    if (this.data != null) {
-      return Arrays.copyOf(this.data, this.data.length);
-    } else {
-      return null;
+    for (DatanodeDetails datanode : datanodes.values()) {
+      builder.addMembers(datanode.getProtoBufMessage());
     }
-  }
+    builder.setLeaderID(leaderID);
 
-  @VisibleForTesting
-  public PipelineChannel getPipelineChannel() {
-    return pipelineChannel;
-  }
+    if (this.getLifeCycleState() != null) {
+      builder.setState(this.getLifeCycleState());
+    }
+    if (this.getType() != null) {
+      builder.setType(this.getType());
+    }
 
-  /**
-   * Set private data on pipeline.
-   *
-   * @param data -- private data.
-   */
-  public void setData(byte[] data) {
-    if (data != null) {
-      this.data = Arrays.copyOf(data, data.length);
+    if (this.getFactor() != null) {
+      builder.setFactor(this.getFactor());
     }
+    return builder.build();
   }
 
   /**
@@ -182,7 +210,7 @@ public class Pipeline {
    * @return - LifeCycleStates.
    */
   public HddsProtos.LifeCycleState getLifeCycleState() {
-    return pipelineChannel.getLifeCycleState();
+    return lifeCycleState;
   }
 
   /**
@@ -191,7 +219,7 @@ public class Pipeline {
    * @return - Name of the pipeline
    */
   public String getPipelineName() {
-    return pipelineChannel.getName();
+    return name;
   }
 
   /**
@@ -200,16 +228,16 @@ public class Pipeline {
    * @return type - Standalone, Ratis, Chained.
    */
   public HddsProtos.ReplicationType getType() {
-    return pipelineChannel.getType();
+    return type;
   }
 
   @Override
   public String toString() {
     final StringBuilder b = new StringBuilder(getClass().getSimpleName())
         .append("[");
-    pipelineChannel.getDatanodes().keySet().stream()
+    getDatanodes().keySet().stream()
         .forEach(id -> b.
-            append(id.endsWith(pipelineChannel.getLeaderID()) ? "*" + id : id));
+            append(id.endsWith(getLeaderID()) ? "*" + id : id));
     b.append(" name:").append(getPipelineName());
     if (getType() != null) {
       b.append(" type:").append(getType().toString());

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/common/helpers/PipelineChannel.java

@@ -1,124 +0,0 @@
-/**
- * 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
- * <p>
- * http://www.apache.org/licenses/LICENSE-2.0
- * <p>
- * 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.hdds.scm.container.common.helpers;
-
-import com.fasterxml.jackson.annotation.JsonIgnore;
-import com.google.common.base.Preconditions;
-import org.apache.hadoop.hdds.protocol.DatanodeDetails;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos.LifeCycleState;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos.ReplicationFactor;
-import org.apache.hadoop.hdds.protocol.proto.HddsProtos.ReplicationType;
-
-import java.util.Map;
-import java.util.TreeMap;
-
-/**
- * PipelineChannel information for a {@link Pipeline}.
- */
-public class PipelineChannel {
-  @JsonIgnore
-  private String leaderID;
-  @JsonIgnore
-  private Map<String, DatanodeDetails> datanodes;
-  private LifeCycleState lifeCycleState;
-  private ReplicationType type;
-  private ReplicationFactor factor;
-  private String name;
-  // TODO: change to long based id
-  //private long id;
-
-  public PipelineChannel(String leaderID, LifeCycleState lifeCycleState,
-      ReplicationType replicationType, ReplicationFactor replicationFactor,
-      String name) {
-    this.leaderID = leaderID;
-    this.lifeCycleState = lifeCycleState;
-    this.type = replicationType;
-    this.factor = replicationFactor;
-    this.name = name;
-    datanodes = new TreeMap<>();
-  }
-
-  public String getLeaderID() {
-    return leaderID;
-  }
-
-  public Map<String, DatanodeDetails> getDatanodes() {
-    return datanodes;
-  }
-
-  public LifeCycleState getLifeCycleState() {
-    return lifeCycleState;
-  }
-
-  public ReplicationType getType() {
-    return type;
-  }
-
-  public ReplicationFactor getFactor() {
-    return factor;
-  }
-
-  public String getName() {
-    return name;
-  }
-
-  public void addMember(DatanodeDetails datanodeDetails) {
-    datanodes.put(datanodeDetails.getUuid().toString(),
-        datanodeDetails);
-  }
-
-  @JsonIgnore
-  public HddsProtos.PipelineChannel getProtobufMessage() {
-    HddsProtos.PipelineChannel.Builder builder =
-        HddsProtos.PipelineChannel.newBuilder();
-    for (DatanodeDetails datanode : datanodes.values()) {
-      builder.addMembers(datanode.getProtoBufMessage());
-    }
-    builder.setLeaderID(leaderID);
-
-    if (this.getLifeCycleState() != null) {
-      builder.setState(this.getLifeCycleState());
-    }
-    if (this.getType() != null) {
-      builder.setType(this.getType());
-    }
-
-    if (this.getFactor() != null) {
-      builder.setFactor(this.getFactor());
-    }
-    return builder.build();
-  }
-
-  public static PipelineChannel getFromProtoBuf(
-      HddsProtos.PipelineChannel transportProtos) {
-    Preconditions.checkNotNull(transportProtos);
-    PipelineChannel pipelineChannel =
-        new PipelineChannel(transportProtos.getLeaderID(),
-            transportProtos.getState(),
-            transportProtos.getType(),
-            transportProtos.getFactor(),
-            transportProtos.getName());
-
-    for (HddsProtos.DatanodeDetailsProto dataID :
-        transportProtos.getMembersList()) {
-      pipelineChannel.addMember(DatanodeDetails.getFromProtoBuf(dataID));
-    }
-    return pipelineChannel;
-  }
-}

hadoop-hdds/common/src/main/proto/hdds.proto

@@ -40,7 +40,7 @@ message Port {
     required uint32 value = 2;
 }
 
-message PipelineChannel {
+message Pipeline {
     required string leaderID = 1;
     repeated DatanodeDetailsProto members = 2;
     optional LifeCycleState state = 3 [default = OPEN];
@@ -49,12 +49,6 @@ message PipelineChannel {
     optional string name = 6;
 }
 
-// A pipeline is composed of PipelineChannel (Ratis/StandAlone) that back a
-// container.
-message Pipeline {
-    required PipelineChannel pipelineChannel = 2;
-}
-
 message KeyValue {
     required string key = 1;
     optional string value = 2;

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/container/closer/ContainerCloser.java

@@ -127,12 +127,12 @@ public class ContainerCloser {
     // to SCM. In that case also, data node will ignore this command.
 
     HddsProtos.Pipeline pipeline = info.getPipeline();
-    for (HddsProtos.DatanodeDetailsProto datanodeDetails : pipeline
-        .getPipelineChannel().getMembersList()) {
+    for (HddsProtos.DatanodeDetailsProto datanodeDetails :
+        pipeline.getMembersList()) {
       nodeManager.addDatanodeCommand(
           DatanodeDetails.getFromProtoBuf(datanodeDetails).getUuid(),
           new CloseContainerCommand(info.getContainerID(),
-              pipeline.getPipelineChannel().getType()));
+              pipeline.getType()));
     }
     if (!commandIssued.containsKey(info.getContainerID())) {
       commandIssued.put(info.getContainerID(),

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/PipelineManager.java

@@ -17,7 +17,6 @@
 package org.apache.hadoop.hdds.scm.pipelines;
 
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdds.protocol.DatanodeDetails;
 import org.apache.hadoop.hdds.protocol.proto.HddsProtos.LifeCycleState;
 import org.apache.hadoop.hdds.protocol.proto.HddsProtos.ReplicationFactor;
@@ -36,12 +35,12 @@ import java.util.concurrent.atomic.AtomicInteger;
 public abstract class PipelineManager {
   private static final Logger LOG =
       LoggerFactory.getLogger(PipelineManager.class);
-  private final List<PipelineChannel> activePipelineChannels;
-  private final AtomicInteger conduitsIndex;
+  private final List<Pipeline> activePipelines;
+  private final AtomicInteger pipelineIndex;
 
   public PipelineManager() {
-    activePipelineChannels = new LinkedList<>();
-    conduitsIndex = new AtomicInteger(0);
+    activePipelines = new LinkedList<>();
+    pipelineIndex = new AtomicInteger(0);
   }
 
   /**
@@ -59,9 +58,9 @@ public abstract class PipelineManager {
     /**
      * In the Ozone world, we have a very simple policy.
      *
-     * 1. Try to create a pipelineChannel if there are enough free nodes.
+     * 1. Try to create a pipeline if there are enough free nodes.
      *
-     * 2. This allows all nodes to part of a pipelineChannel quickly.
+     * 2. This allows all nodes to part of a pipeline quickly.
      *
      * 3. if there are not enough free nodes, return conduits in a
      * round-robin fashion.
@@ -70,28 +69,28 @@ public abstract class PipelineManager {
      * Create a new placement policy that returns conduits in round robin
      * fashion.
      */
-    PipelineChannel pipelineChannel =
-        allocatePipelineChannel(replicationFactor);
-    if (pipelineChannel != null) {
-      LOG.debug("created new pipelineChannel:{} for container with " +
+    Pipeline pipeline =
+        allocatePipeline(replicationFactor);
+    if (pipeline != null) {
+      LOG.debug("created new pipeline:{} for container with " +
               "replicationType:{} replicationFactor:{}",
-          pipelineChannel.getName(), replicationType, replicationFactor);
-      activePipelineChannels.add(pipelineChannel);
+          pipeline.getPipelineName(), replicationType, replicationFactor);
+      activePipelines.add(pipeline);
     } else {
-      pipelineChannel =
-          findOpenPipelineChannel(replicationType, replicationFactor);
-      if (pipelineChannel != null) {
-        LOG.debug("re-used pipelineChannel:{} for container with " +
+      pipeline =
+          findOpenPipeline(replicationType, replicationFactor);
+      if (pipeline != null) {
+        LOG.debug("re-used pipeline:{} for container with " +
                 "replicationType:{} replicationFactor:{}",
-            pipelineChannel.getName(), replicationType, replicationFactor);
+            pipeline.getPipelineName(), replicationType, replicationFactor);
       }
     }
-    if (pipelineChannel == null) {
-      LOG.error("Get pipelineChannel call failed. We are not able to find" +
-              "free nodes or operational pipelineChannel.");
+    if (pipeline == null) {
+      LOG.error("Get pipeline call failed. We are not able to find" +
+              "free nodes or operational pipeline.");
       return null;
     } else {
-      return new Pipeline(pipelineChannel);
+      return pipeline;
     }
   }
 
@@ -106,19 +105,19 @@ public abstract class PipelineManager {
     }
   }
 
-  public abstract PipelineChannel allocatePipelineChannel(
+  public abstract Pipeline allocatePipeline(
       ReplicationFactor replicationFactor) throws IOException;
 
   /**
-   * Find a PipelineChannel that is operational.
+   * Find a Pipeline that is operational.
    *
    * @return - Pipeline or null
    */
-  private PipelineChannel findOpenPipelineChannel(
+  private Pipeline findOpenPipeline(
       ReplicationType type, ReplicationFactor factor) {
-    PipelineChannel pipelineChannel = null;
+    Pipeline pipeline = null;
     final int sentinal = -1;
-    if (activePipelineChannels.size() == 0) {
+    if (activePipelines.size() == 0) {
       LOG.error("No Operational conduits found. Returning null.");
       return null;
     }
@@ -126,26 +125,26 @@ public abstract class PipelineManager {
     int nextIndex = sentinal;
     for (; startIndex != nextIndex; nextIndex = getNextIndex()) {
       // Just walk the list in a circular way.
-      PipelineChannel temp =
-          activePipelineChannels
+      Pipeline temp =
+          activePipelines
               .get(nextIndex != sentinal ? nextIndex : startIndex);
-      // if we find an operational pipelineChannel just return that.
+      // if we find an operational pipeline just return that.
       if ((temp.getLifeCycleState() == LifeCycleState.OPEN) &&
           (temp.getFactor() == factor) && (temp.getType() == type)) {
-        pipelineChannel = temp;
+        pipeline = temp;
         break;
       }
     }
-    return pipelineChannel;
+    return pipeline;
   }
 
   /**
-   * gets the next index of the PipelineChannel to get.
+   * gets the next index of the Pipeline to get.
    *
    * @return index in the link list to get.
    */
   private int getNextIndex() {
-    return conduitsIndex.incrementAndGet() % activePipelineChannels.size();
+    return pipelineIndex.incrementAndGet() % activePipelines.size();
   }
 
   /**

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/PipelineSelector.java

@@ -20,7 +20,6 @@ import com.google.common.base.Preconditions;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdds.scm.ScmConfigKeys;
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdds.scm.container.placement.algorithms
     .ContainerPlacementPolicy;
 import org.apache.hadoop.hdds.scm.container.placement.algorithms
@@ -85,20 +84,20 @@ public class PipelineSelector {
    * The first of the list will be the leader node.
    * @return pipeline corresponding to nodes
    */
-  public static PipelineChannel newPipelineFromNodes(
+  public static Pipeline newPipelineFromNodes(
       List<DatanodeDetails> nodes, LifeCycleState state,
       ReplicationType replicationType, ReplicationFactor replicationFactor,
       String name) {
     Preconditions.checkNotNull(nodes);
     Preconditions.checkArgument(nodes.size() > 0);
     String leaderId = nodes.get(0).getUuidString();
-    PipelineChannel
-        pipelineChannel = new PipelineChannel(leaderId, state, replicationType,
+    Pipeline
+        pipeline = new Pipeline(leaderId, state, replicationType,
         replicationFactor, name);
     for (DatanodeDetails node : nodes) {
-      pipelineChannel.addMember(node);
+      pipeline.addMember(node);
     }
-    return pipelineChannel;
+    return pipeline;
   }
 
   /**

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/ratis/RatisManagerImpl.java

@@ -20,7 +20,6 @@ import com.google.common.base.Preconditions;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdds.scm.XceiverClientRatis;
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdds.scm.container.placement.algorithms
     .ContainerPlacementPolicy;
 import org.apache.hadoop.hdds.scm.node.NodeManager;
@@ -68,12 +67,12 @@ public class RatisManagerImpl extends PipelineManager {
   }
 
   /**
-   * Allocates a new ratis PipelineChannel from the free nodes.
+   * Allocates a new ratis Pipeline from the free nodes.
    *
    * @param factor - One or Three
    * @return PipelineChannel.
    */
-  public PipelineChannel allocatePipelineChannel(ReplicationFactor factor) {
+  public Pipeline allocatePipeline(ReplicationFactor factor) {
     List<DatanodeDetails> newNodesList = new LinkedList<>();
     List<DatanodeDetails> datanodes = nodeManager.getNodes(NodeState.HEALTHY);
     int count = getReplicationCount(factor);
@@ -87,22 +86,20 @@ public class RatisManagerImpl extends PipelineManager {
           // once a datanode has been added to a pipeline, exclude it from
           // further allocations
           ratisMembers.addAll(newNodesList);
-          LOG.info("Allocating a new ratis pipelineChannel of size: {}", count);
+          LOG.info("Allocating a new ratis pipeline of size: {}", count);
           // Start all channel names with "Ratis", easy to grep the logs.
           String conduitName = PREFIX +
               UUID.randomUUID().toString().substring(PREFIX.length());
-          PipelineChannel pipelineChannel =
+          Pipeline pipeline=
               PipelineSelector.newPipelineFromNodes(newNodesList,
               LifeCycleState.OPEN, ReplicationType.RATIS, factor, conduitName);
-          Pipeline pipeline =
-              new Pipeline(pipelineChannel);
           try (XceiverClientRatis client =
               XceiverClientRatis.newXceiverClientRatis(pipeline, conf)) {
             client.createPipeline(pipeline.getPipelineName(), newNodesList);
           } catch (IOException e) {
             return null;
           }
-          return pipelineChannel;
+          return pipeline;
         }
       }
     }

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/standalone/StandaloneManagerImpl.java

@@ -17,7 +17,7 @@
 package org.apache.hadoop.hdds.scm.pipelines.standalone;
 
 import com.google.common.base.Preconditions;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
+import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
 import org.apache.hadoop.hdds.scm.container.placement.algorithms
     .ContainerPlacementPolicy;
 import org.apache.hadoop.hdds.scm.node.NodeManager;
@@ -67,12 +67,12 @@ public class StandaloneManagerImpl extends PipelineManager {
 
 
   /**
-   * Allocates a new standalone PipelineChannel from the free nodes.
+   * Allocates a new standalone Pipeline from the free nodes.
    *
    * @param factor - One
-   * @return PipelineChannel.
+   * @return Pipeline.
    */
-  public PipelineChannel allocatePipelineChannel(ReplicationFactor factor) {
+  public Pipeline allocatePipeline(ReplicationFactor factor) {
     List<DatanodeDetails> newNodesList = new LinkedList<>();
     List<DatanodeDetails> datanodes = nodeManager.getNodes(NodeState.HEALTHY);
     int count = getReplicationCount(factor);

hadoop-hdds/server-scm/src/test/java/org/apache/hadoop/hdds/scm/block/TestDeletedBlockLog.java

@@ -23,7 +23,6 @@ import org.apache.hadoop.hdds.scm.container.ContainerMapping;
 import org.apache.hadoop.hdds.scm.container.Mapping;
 import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdds.conf.OzoneConfiguration;
 import org.apache.hadoop.hdds.protocol.DatanodeDetails;
@@ -357,11 +356,10 @@ public class TestDeletedBlockLog {
 
   private void mockContainerInfo(Mapping mappingService, long containerID,
       DatanodeDetails dd) throws IOException {
-    PipelineChannel pipelineChannel =
-        new PipelineChannel("fake", LifeCycleState.OPEN,
+    Pipeline pipeline =
+        new Pipeline("fake", LifeCycleState.OPEN,
             ReplicationType.STAND_ALONE, ReplicationFactor.ONE, "fake");
-    pipelineChannel.addMember(dd);
-    Pipeline pipeline = new Pipeline(pipelineChannel);
+    pipeline.addMember(dd);
 
     ContainerInfo.Builder builder = new ContainerInfo.Builder();
     builder.setPipeline(pipeline);

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/TestMiniOzoneCluster.java

@@ -28,7 +28,6 @@ import org.apache.hadoop.ozone.container.ozoneimpl.TestOzoneContainer;
 import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
 import org.apache.hadoop.hdds.scm.TestUtils;
 import org.apache.hadoop.hdds.scm.XceiverClient;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
 import org.apache.hadoop.test.PathUtils;
 import org.apache.hadoop.test.TestGenericTestUtils;
@@ -92,13 +91,12 @@ public class TestMiniOzoneCluster {
     for(HddsDatanodeService dn : datanodes) {
       // Create a single member pipe line
       DatanodeDetails datanodeDetails = dn.getDatanodeDetails();
-      final PipelineChannel pipelineChannel =
-          new PipelineChannel(datanodeDetails.getUuidString(),
+      final Pipeline pipeline =
+          new Pipeline(datanodeDetails.getUuidString(),
               HddsProtos.LifeCycleState.OPEN,
               HddsProtos.ReplicationType.STAND_ALONE,
               HddsProtos.ReplicationFactor.ONE, "test");
-      pipelineChannel.addMember(datanodeDetails);
-      Pipeline pipeline = new Pipeline(pipelineChannel);
+      pipeline.addMember(datanodeDetails);
 
       // Verify client is able to connect to the container
       try (XceiverClient client = new XceiverClient(pipeline, conf)){

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/container/ContainerTestHelper.java

@@ -37,7 +37,6 @@ import org.apache.hadoop.hdds.conf.OzoneConfiguration;
 import org.apache.hadoop.ozone.OzoneConsts;
 import org.apache.hadoop.ozone.container.common.helpers.ChunkInfo;
 import org.apache.hadoop.ozone.container.common.helpers.KeyData;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.apache.hadoop.util.Time;
@@ -136,14 +135,14 @@ public final class ContainerTestHelper {
     Preconditions.checkArgument(i.hasNext());
     final DatanodeDetails leader = i.next();
     String pipelineName = "TEST-" + UUID.randomUUID().toString().substring(3);
-    final PipelineChannel pipelineChannel =
-        new PipelineChannel(leader.getUuidString(), LifeCycleState.OPEN,
+    final Pipeline pipeline =
+        new Pipeline(leader.getUuidString(), LifeCycleState.OPEN,
             ReplicationType.STAND_ALONE, ReplicationFactor.ONE, pipelineName);
-    pipelineChannel.addMember(leader);
+    pipeline.addMember(leader);
     for(; i.hasNext();) {
-      pipelineChannel.addMember(i.next());
+      pipeline.addMember(i.next());
     }
-    return new Pipeline(pipelineChannel);
+    return pipeline;
   }
 
   /**
@@ -207,8 +206,6 @@ public final class ContainerTestHelper {
         ContainerProtos.WriteChunkRequestProto
             .newBuilder();
 
-    Pipeline newPipeline =
-        new Pipeline(pipeline.getPipelineChannel());
     writeRequest.setBlockID(blockID.getDatanodeBlockIDProtobuf());
 
     byte[] data = getData(datalen);
@@ -223,7 +220,7 @@ public final class ContainerTestHelper {
     request.setCmdType(ContainerProtos.Type.WriteChunk);
     request.setWriteChunk(writeRequest);
     request.setTraceID(UUID.randomUUID().toString());
-    request.setDatanodeUuid(newPipeline.getLeader().getUuidString());
+    request.setDatanodeUuid(pipeline.getLeader().getUuidString());
 
     return request.build();
   }
@@ -241,8 +238,6 @@ public final class ContainerTestHelper {
       throws Exception {
     ContainerProtos.PutSmallFileRequestProto.Builder smallFileRequest =
         ContainerProtos.PutSmallFileRequestProto.newBuilder();
-    Pipeline newPipeline =
-        new Pipeline(pipeline.getPipelineChannel());
     byte[] data = getData(dataLen);
     ChunkInfo info = getChunk(blockID.getLocalID(), 0, 0, dataLen);
     setDataChecksum(info, data);
@@ -266,7 +261,7 @@ public final class ContainerTestHelper {
     request.setCmdType(ContainerProtos.Type.PutSmallFile);
     request.setPutSmallFile(smallFileRequest);
     request.setTraceID(UUID.randomUUID().toString());
-    request.setDatanodeUuid(newPipeline.getLeader().getUuidString());
+    request.setDatanodeUuid(pipeline.getLeader().getUuidString());
     return request.build();
   }
 

hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/genesis/BenchMarkContainerStateMap.java

@@ -24,7 +24,6 @@ import org.apache.hadoop.hdds.protocol.proto.HddsProtos.ReplicationType;
 import org.apache.hadoop.hdds.protocol.DatanodeDetails;
 import org.apache.hadoop.hdds.scm.container.common.helpers.ContainerInfo;
 import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.hdds.scm.container.states.ContainerStateMap;
 import org.apache.hadoop.hdds.scm.exceptions.SCMException;
 import org.apache.hadoop.util.Time;
@@ -150,14 +149,14 @@ public class BenchMarkContainerStateMap {
     Preconditions.checkArgument(i.hasNext());
     final DatanodeDetails leader = i.next();
     String pipelineName = "TEST-" + UUID.randomUUID().toString().substring(5);
-    final PipelineChannel pipelineChannel =
-        new PipelineChannel(leader.getUuidString(), OPEN,
+    final Pipeline pipeline =
+        new Pipeline(leader.getUuidString(), OPEN,
             ReplicationType.STAND_ALONE, ReplicationFactor.ONE, pipelineName);
-    pipelineChannel.addMember(leader);
+    pipeline.addMember(leader);
     for (; i.hasNext();) {
-      pipelineChannel.addMember(i.next());
+      pipeline.addMember(i.next());
     }
-    return new Pipeline(pipelineChannel);
+    return pipeline;
   }
 
   @Benchmark

hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/genesis/BenchMarkDatanodeDispatcher.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.ozone.genesis;
 
+import org.apache.hadoop.hdds.scm.container.common.helpers.Pipeline;
 import org.apache.ratis.shaded.com.google.protobuf.ByteString;
 import org.apache.commons.codec.digest.DigestUtils;
 import org.apache.commons.io.FileUtils;
@@ -32,7 +33,6 @@ import org.apache.hadoop.ozone.container.common.impl.Dispatcher;
 import org.apache.hadoop.ozone.container.common.impl.KeyManagerImpl;
 import org.apache.hadoop.ozone.container.common.interfaces.ContainerManager;
 
-import org.apache.hadoop.hdds.scm.container.common.helpers.PipelineChannel;
 import org.apache.hadoop.util.Time;
 import org.openjdk.jmh.annotations.Benchmark;
 import org.openjdk.jmh.annotations.Level;
@@ -78,7 +78,7 @@ public class BenchMarkDatanodeDispatcher {
   private String baseDir;
   private String datanodeUuid;
   private Dispatcher dispatcher;
-  private PipelineChannel pipelineChannel;
+  private Pipeline pipeline;
   private ByteString data;
   private Random random;
   private AtomicInteger containerCount;
@@ -96,7 +96,7 @@ public class BenchMarkDatanodeDispatcher {
   @Setup(Level.Trial)
   public void initialize() throws IOException {
     datanodeUuid = UUID.randomUUID().toString();
-    pipelineChannel = new PipelineChannel("127.0.0.1",
+    pipeline = new Pipeline("127.0.0.1",
         LifeCycleState.OPEN, ReplicationType.STAND_ALONE,
         ReplicationFactor.ONE, "SA-" + UUID.randomUUID());
 

hadoop-ozone/tools/src/main/java/org/apache/hadoop/ozone/scm/cli/SQLCLI.java

@@ -519,11 +519,11 @@ public class SQLCLI  extends Configured implements Tool {
     LOG.info("Insert to sql container db, for container {}", containerID);
     String insertContainerInfo = String.format(
         INSERT_CONTAINER_INFO, containerID,
-        pipeline.getPipelineChannel().getLeaderID());
+        pipeline.getLeaderID());
     executeSQL(conn, insertContainerInfo);
 
     for (HddsProtos.DatanodeDetailsProto dd :
-        pipeline.getPipelineChannel().getMembersList()) {
+        pipeline.getMembersList()) {
       String uuid = dd.getUuid();
       if (!uuidChecked.contains(uuid)) {
         // we may also not use this checked set, but catch exception instead