HDFS-8573. Move creation of restartMeta file logic from BlockReceiver to ReplicaInPipeline. Contributed by Eddy Xu.

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

@@ -620,6 +620,9 @@ Release 2.8.0 - UNRELEASED
 
     HDFS-8549. Abort the balancer if an upgrade is in progress. (wang)
 
+    HDFS-8573. Move creation of restartMeta file logic from BlockReceiver to
+    ReplicaInPipeline. (Eddy Xu via wang)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than

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

@@ -23,7 +23,6 @@ import java.io.BufferedOutputStream;
 import java.io.Closeable;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
-import java.io.File;
 import java.io.FileDescriptor;
 import java.io.FileOutputStream;
 import java.io.IOException;
@@ -839,15 +838,8 @@ class BlockReceiver implements Closeable {
           // In case this datanode is shutting down for quick restart,
           // send a special ack upstream.
           if (datanode.isRestarting() && isClient && !isTransfer) {
-            File blockFile = ((ReplicaInPipeline)replicaInfo).getBlockFile();
-            File restartMeta = new File(blockFile.getParent()  + 
-                File.pathSeparator + "." + blockFile.getName() + ".restart");
-            if (restartMeta.exists() && !restartMeta.delete()) {
-              LOG.warn("Failed to delete restart meta file: " +
-                  restartMeta.getPath());
-            }
             try (Writer out = new OutputStreamWriter(
-                new FileOutputStream(restartMeta), "UTF-8")) {
+                replicaInfo.createRestartMetaStream(), "UTF-8")) {
               // write out the current time.
               out.write(Long.toString(Time.now() + restartBudget));
               out.flush();

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

@@ -20,6 +20,7 @@ package org.apache.hadoop.hdfs.server.datanode;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.OutputStream;
 import java.io.RandomAccessFile;
 
 import org.apache.hadoop.hdfs.protocol.Block;
@@ -287,7 +288,19 @@ public class ReplicaInPipeline extends ReplicaInfo
       throw e;
     }
   }
-  
+
+  @Override
+  public OutputStream createRestartMetaStream() throws IOException {
+    File blockFile = getBlockFile();
+    File restartMeta = new File(blockFile.getParent()  +
+        File.pathSeparator + "." + blockFile.getName() + ".restart");
+    if (restartMeta.exists() && !restartMeta.delete()) {
+      DataNode.LOG.warn("Failed to delete restart meta file: " +
+          restartMeta.getPath());
+    }
+    return new FileOutputStream(restartMeta);
+  }
+
   @Override
   public String toString() {
     return super.toString()

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

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hdfs.server.datanode;
 
 import java.io.IOException;
+import java.io.OutputStream;
 
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.ReplicaOutputStreams;
 import org.apache.hadoop.util.DataChecksum;
@@ -73,4 +74,13 @@ public interface ReplicaInPipelineInterface extends Replica {
    */
   public ReplicaOutputStreams createStreams(boolean isCreate,
       DataChecksum requestedChecksum) throws IOException;
+
+  /**
+   * Create an output stream to write restart metadata in case of datanode
+   * shutting down for quick restart.
+   *
+   * @return output stream for writing.
+   * @throws IOException if any error occurs
+   */
+  public OutputStream createRestartMetaStream() throws IOException;
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/SimulatedFSDataset.java

@@ -262,6 +262,11 @@ public class SimulatedFSDataset implements FsDatasetSpi<FsVolumeSpi> {
       }
     }
 
+    @Override
+    public OutputStream createRestartMetaStream() throws IOException {
+      return new SimulatedOutputStream();
+    }
+
     @Override
     synchronized public long getBlockId() {
       return theBlock.getBlockId();

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/extdataset/ExternalReplicaInPipeline.java

@@ -19,6 +19,8 @@
 package org.apache.hadoop.hdfs.server.datanode.extdataset;
 
 import java.io.IOException;
+import java.io.OutputStream;
+
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.ReplicaState;
 import org.apache.hadoop.hdfs.server.datanode.ChunkChecksum;
 import org.apache.hadoop.hdfs.server.datanode.ReplicaInPipelineInterface;
@@ -59,6 +61,11 @@ public class ExternalReplicaInPipeline implements ReplicaInPipelineInterface {
     return new ReplicaOutputStreams(null, null, requestedChecksum, false);
   }
 
+  @Override
+  public OutputStream createRestartMetaStream() throws IOException {
+    return null;
+  }
+
   @Override
   public long getBlockId() {
     return 0;