Fix #183 by sorting multi-action RPCs by row key as well as region so that

if a later version of HBase is used that sorts the requests on receipt then
the RPCs will still match up with the responses.

Signed-off-by: Chris Larsen <clarsen@yahoo-inc.com>

Author: manolama

src/MultiAction.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2010-2016  The Async HBase Authors.  All rights reserved.
+ * Copyright (C) 2010-2018  The Async HBase Authors.  All rights reserved.
  * This file is part of Async HBase.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -45,6 +45,11 @@
  * <p>
  * This RPC is guaranteed to be sent atomically (but HBase doesn't guarantee
  * that it will apply it atomically).
+ * <p>
+ * Before serializing, the RPCs are sorted by region and (as of 1.8.1)
+ * by row key (to fix issues with 
+ * https://issues.apache.org/jira/browse/HBASE-17924) so that the 
+ * responses can be matched to the original RPC.
  */
 final class MultiAction extends HBaseRpc implements HBaseRpc.IsEdit {
 
@@ -70,7 +75,7 @@ final class MultiAction extends HBaseRpc implements HBaseRpc.IsEdit {
   private static final byte[] MULTI = { 'm', 'u', 'l', 't', 'i' };
 
   /** RPC method name for HBase 0.95 and above.  */
-  private static final byte[] MMULTI = { 'M', 'u', 'l', 't', 'i' };
+  static final byte[] MMULTI = { 'M', 'u', 'l', 't', 'i' };
 
   /** Template for NSREs.  */
   private static final NotServingRegionException NSRE =
@@ -214,7 +219,7 @@ ChannelBuffer serialize(final byte server_version) {
     }
 
     // we create a new RegionAction for each region.
-    Collections.sort(batch, SORT_BY_REGION);
+    Collections.sort(batch, SORT_BY_REGION_AND_KEY);
     final MultiRequest.Builder req = MultiRequest.newBuilder();
     RegionAction.Builder actions = null;
     byte[] prev_region = HBaseClient.EMPTY_ARRAY;
@@ -508,24 +513,30 @@ public int compare(final BatchableRpc a, final BatchableRpc b) {
   }
 
   /**
-   * Sorts {@link BatchableRpc}s appropriately for HBase 0.95+ multi-action.
+   * Sorts {@link BatchableRpc}s appropriately for HBase 0.95+ multi-action
+   * as well as 1.3x where the response is also sorted by key.
    */
-  static final RegionComparator SORT_BY_REGION = new RegionComparator();
+  static final RegionAndKeyComparator SORT_BY_REGION_AND_KEY = 
+      new RegionAndKeyComparator();
 
   /**
    * Sorts {@link BatchableRpc}s by region.
    * Used with HBase 0.95+ only.
    */
-  private static final class RegionComparator
+  private static final class RegionAndKeyComparator
     implements Comparator<BatchableRpc> {
 
-    private RegionComparator() {  // Can't instantiate outside of this class.
+    private RegionAndKeyComparator() {  // Can't instantiate outside of this class.
     }
 
     @Override
     /** Compares two RPCs.  */
     public int compare(final BatchableRpc a, final BatchableRpc b) {
-      return Bytes.memcmp(a.getRegion().name(), b.getRegion().name());
+      int region_cmp = Bytes.memcmp(a.getRegion().name(), b.getRegion().name());
+      if (region_cmp != 0) {
+        return region_cmp;
+      }
+      return Bytes.memcmp(a.key, b.key);
     }
 
   }

test/TestMultiAction.java

@@ -26,6 +26,7 @@
  */
 package org.hbase.async;
 
+import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
@@ -40,7 +41,9 @@
 import java.util.Collections;
 import java.util.List;
 
+import org.hbase.async.generated.ClientPB.MultiRequest;
 import org.hbase.async.generated.ClientPB.MultiResponse;
+import org.hbase.async.generated.ClientPB.RegionAction;
 import org.hbase.async.generated.ClientPB.RegionActionResult;
 import org.hbase.async.generated.ClientPB.ResultOrException;
 import org.hbase.async.generated.ClientPB.RegionActionResult.Builder;
@@ -212,6 +215,48 @@ public void addErrors() throws Exception {
   }
 
   // NOTE: The following are tests for HBase 0.96 and up
+  
+  @Test
+  public void serdesOrdering() throws Exception {
+    PutRequest put1 = new PutRequest(TABLE, concat(KEY, new byte[] { 2 }), 
+        FAMILY, QUALIFIER, VALUE);
+    put1.region = region;
+    PutRequest put2 = new PutRequest(TABLE, KEY, FAMILY, "myqual".getBytes(), VALUE);
+    put2.region = region;
+    PutRequest put3 = new PutRequest(TABLE, concat(KEY, new byte[] { 2 }), 
+        FAMILY, "myqual".getBytes(), VALUE);
+    put3.region = region2;
+    PutRequest put4 = new PutRequest(TABLE, KEY, FAMILY, "myqual".getBytes(), VALUE);
+    put4.region = region2;
+    MultiAction multi = new MultiAction();
+    multi.add(put1);
+    multi.add(put2);
+    multi.add(put3);
+    multi.add(put4);
+    
+    ChannelBuffer buffer = multi.serialize(RegionClient.SERVER_VERSION_095_OR_ABOVE);
+    buffer.readerIndex(4 + 19 + MultiAction.MMULTI.length);
+    HBaseRpc.readProtoBufVarint(buffer);
+    byte[] bytes = new byte[buffer.writerIndex() - buffer.readerIndex()];
+    buffer.readBytes(bytes);
+    MultiRequest parsed = MultiRequest.parseFrom(bytes);
+    assertEquals(2, parsed.getRegionActionCount());
+    
+    RegionAction actions = parsed.getRegionAction(0);
+    assertEquals(2, actions.getActionCount());
+    assertArrayEquals(region.name(), actions.getRegion().getValue().toByteArray());
+    assertArrayEquals(KEY, actions.getAction(0).getMutation().getRow().toByteArray());
+    assertArrayEquals(concat(KEY, new byte[] { 2 }), 
+        actions.getAction(1).getMutation().getRow().toByteArray());
+    
+    actions = parsed.getRegionAction(1);
+    assertEquals(2, actions.getActionCount());
+    assertArrayEquals(region2.name(), actions.getRegion().getValue().toByteArray());
+    assertArrayEquals(KEY, actions.getAction(0).getMutation().getRow().toByteArray());
+    assertArrayEquals(concat(KEY, new byte[] { 2 }), 
+        actions.getAction(1).getMutation().getRow().toByteArray());
+  }
+  
   @Test
   public void deserializePuts() throws Exception {
     final List<ResultOrException> results = new ArrayList<ResultOrException>(2);
@@ -870,7 +915,7 @@ public void deserializeMultiRegionOneFailed() throws Exception {
     multi.add(put2);
     multi.add(put3);
     multi.add(put4);
-    Collections.sort(multi.batch(), MultiAction.SORT_BY_REGION);
+    Collections.sort(multi.batch(), MultiAction.SORT_BY_REGION_AND_KEY);
 
     final MultiAction.Response decoded = 
         (MultiAction.Response)multi.deserialize(
@@ -916,7 +961,7 @@ public void deserializeMultiRegionTwoFailed() throws Exception {
     multi.add(put2);
     multi.add(put3);
     multi.add(put4);
-    Collections.sort(multi.batch(), MultiAction.SORT_BY_REGION);
+    Collections.sort(multi.batch(), MultiAction.SORT_BY_REGION_AND_KEY);
 
     final MultiAction.Response decoded = 
         (MultiAction.Response)multi.deserialize(