HBASE-21084 When cloning a snapshot including a split parent region, the split parent region of the cloned table will be online

hbase-server/src/main/java/org/apache/hadoop/hbase/master/procedure/CloneSnapshotProcedure.java

@@ -39,6 +39,8 @@ import org.apache.hadoop.hbase.errorhandling.ForeignExceptionDispatcher;
 import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
 import org.apache.hadoop.hbase.master.MasterFileSystem;
 import org.apache.hadoop.hbase.master.MetricsSnapshot;
+import org.apache.hadoop.hbase.master.RegionState;
+import org.apache.hadoop.hbase.master.assignment.AssignmentManager;
 import org.apache.hadoop.hbase.master.procedure.CreateTableProcedure.CreateHdfsRegions;
 import org.apache.hadoop.hbase.monitoring.MonitoredTask;
 import org.apache.hadoop.hbase.monitoring.TaskMonitor;
@@ -149,7 +151,26 @@ public class CloneSnapshotProcedure
           break;
         case CLONE_SNAPSHOT_ASSIGN_REGIONS:
           CreateTableProcedure.setEnablingState(env, getTableName());
-          addChildProcedure(env.getAssignmentManager().createRoundRobinAssignProcedures(newRegions));
+
+          // Separate newRegions to split regions and regions to assign
+          List<RegionInfo> splitRegions = new ArrayList<>();
+          List<RegionInfo> regionsToAssign = new ArrayList<>();
+          newRegions.forEach(ri -> {
+            if (ri.isOffline() && (ri.isSplit() || ri.isSplitParent())) {
+              splitRegions.add(ri);
+            } else {
+              regionsToAssign.add(ri);
+            }
+          });
+
+          // For split regions, add them to RegionStates
+          AssignmentManager am = env.getAssignmentManager();
+          splitRegions.forEach(ri ->
+            am.getRegionStates().updateRegionState(ri, RegionState.State.SPLIT)
+          );
+
+          addChildProcedure(env.getAssignmentManager()
+            .createRoundRobinAssignProcedures(regionsToAssign));
           setNextState(CloneSnapshotState.CLONE_SNAPSHOT_UPDATE_DESC_CACHE);
           break;
         case CLONE_SNAPSHOT_UPDATE_DESC_CACHE:

hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestCloneSnapshotFromClient.java

@@ -17,13 +17,19 @@
  */
 package org.apache.hadoop.hbase.client;
 
+import static org.junit.Assert.assertEquals;
+
 import java.io.IOException;
+import java.util.List;
+
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtility;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
 import org.apache.hadoop.hbase.NamespaceNotFoundException;
 import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.master.RegionState;
+import org.apache.hadoop.hbase.master.assignment.RegionStates;
 import org.apache.hadoop.hbase.master.snapshot.SnapshotManager;
 import org.apache.hadoop.hbase.snapshot.SnapshotDoesNotExistException;
 import org.apache.hadoop.hbase.snapshot.SnapshotTestingUtils;
@@ -160,7 +166,8 @@ public class TestCloneSnapshotFromClient {
   @Test(expected=SnapshotDoesNotExistException.class)
   public void testCloneNonExistentSnapshot() throws IOException, InterruptedException {
     String snapshotName = "random-snapshot-" + System.currentTimeMillis();
-    final TableName tableName = TableName.valueOf(name.getMethodName() + "-" + System.currentTimeMillis());
+    final TableName tableName = TableName.valueOf(name.getMethodName() + "-"
+      + System.currentTimeMillis());
     admin.cloneSnapshot(snapshotName, tableName);
   }
 
@@ -172,7 +179,8 @@ public class TestCloneSnapshotFromClient {
 
   @Test
   public void testCloneSnapshot() throws IOException, InterruptedException {
-    final TableName clonedTableName = TableName.valueOf(name.getMethodName() + "-" + System.currentTimeMillis());
+    final TableName clonedTableName = TableName.valueOf(name.getMethodName() + "-"
+      + System.currentTimeMillis());
     testCloneSnapshot(clonedTableName, snapshotName0, snapshot0Rows);
     testCloneSnapshot(clonedTableName, snapshotName1, snapshot1Rows);
     testCloneSnapshot(clonedTableName, emptySnapshot, 0);
@@ -196,7 +204,8 @@ public class TestCloneSnapshotFromClient {
   public void testCloneSnapshotCrossNamespace() throws IOException, InterruptedException {
     String nsName = "testCloneSnapshotCrossNamespace";
     admin.createNamespace(NamespaceDescriptor.create(nsName).build());
-    final TableName clonedTableName = TableName.valueOf(nsName, name.getMethodName() + "-" + System.currentTimeMillis());
+    final TableName clonedTableName = TableName.valueOf(nsName, name.getMethodName()
+      + "-" + System.currentTimeMillis());
     testCloneSnapshot(clonedTableName, snapshotName0, snapshot0Rows);
     testCloneSnapshot(clonedTableName, snapshotName1, snapshot1Rows);
     testCloneSnapshot(clonedTableName, emptySnapshot, 0);
@@ -208,7 +217,8 @@ public class TestCloneSnapshotFromClient {
   @Test
   public void testCloneLinksAfterDelete() throws IOException, InterruptedException {
     // Clone a table from the first snapshot
-    final TableName clonedTableName = TableName.valueOf(name.getMethodName() + "1-" + System.currentTimeMillis());
+    final TableName clonedTableName = TableName.valueOf(name.getMethodName() + "1-"
+      + System.currentTimeMillis());
     admin.cloneSnapshot(snapshotName0, clonedTableName);
     verifyRowCount(TEST_UTIL, clonedTableName, snapshot0Rows);
 
@@ -217,7 +227,8 @@ public class TestCloneSnapshotFromClient {
     admin.snapshot(snapshotName2, clonedTableName);
 
     // Clone the snapshot of the cloned table
-    final TableName clonedTableName2 = TableName.valueOf(name.getMethodName() + "2-" + System.currentTimeMillis());
+    final TableName clonedTableName2 = TableName.valueOf(name.getMethodName() + "2-"
+      + System.currentTimeMillis());
     admin.cloneSnapshot(snapshotName2, clonedTableName2);
     verifyRowCount(TEST_UTIL, clonedTableName2, snapshot0Rows);
     admin.disableTable(clonedTableName2);
@@ -244,7 +255,8 @@ public class TestCloneSnapshotFromClient {
     verifyRowCount(TEST_UTIL, clonedTableName2, snapshot0Rows);
 
     // Clone a new table from cloned
-    final TableName clonedTableName3 = TableName.valueOf(name.getMethodName() + "3-" + System.currentTimeMillis());
+    final TableName clonedTableName3 = TableName.valueOf(name.getMethodName() + "3-"
+      + System.currentTimeMillis());
     admin.cloneSnapshot(snapshotName2, clonedTableName3);
     verifyRowCount(TEST_UTIL, clonedTableName3, snapshot0Rows);
 
@@ -254,6 +266,49 @@ public class TestCloneSnapshotFromClient {
     admin.deleteSnapshot(snapshotName2);
   }
 
+  @Test
+  public void testCloneSnapshotAfterSplittingRegion() throws IOException, InterruptedException {
+    // Turn off the CatalogJanitor
+    admin.catalogJanitorSwitch(false);
+
+    try {
+      List<RegionInfo> regionInfos = admin.getRegions(tableName);
+      RegionReplicaUtil.removeNonDefaultRegions(regionInfos);
+
+      // Split the first region
+      splitRegion(regionInfos.get(0));
+
+      // Take a snapshot
+      admin.snapshot(snapshotName2, tableName);
+
+      // Clone the snapshot to another table
+      TableName clonedTableName = TableName.valueOf(name.getMethodName() + "-"
+        + System.currentTimeMillis());
+      admin.cloneSnapshot(snapshotName2, clonedTableName);
+      SnapshotTestingUtils.waitForTableToBeOnline(TEST_UTIL, clonedTableName);
+
+      RegionStates regionStates =
+        TEST_UTIL.getHBaseCluster().getMaster().getAssignmentManager().getRegionStates();
+
+      // The region count of the cloned table should be the same as the one of the original table
+      int openRegionCountOfOriginalTable =
+        regionStates.getRegionByStateOfTable(tableName).get(RegionState.State.OPEN).size();
+      int openRegionCountOfClonedTable =
+        regionStates.getRegionByStateOfTable(clonedTableName).get(RegionState.State.OPEN).size();
+      assertEquals(openRegionCountOfOriginalTable, openRegionCountOfClonedTable);
+
+      int splitRegionCountOfOriginalTable =
+        regionStates.getRegionByStateOfTable(tableName).get(RegionState.State.SPLIT).size();
+      int splitRegionCountOfClonedTable =
+        regionStates.getRegionByStateOfTable(clonedTableName).get(RegionState.State.SPLIT).size();
+      assertEquals(splitRegionCountOfOriginalTable, splitRegionCountOfClonedTable);
+
+      TEST_UTIL.deleteTable(clonedTableName);
+    } finally {
+      admin.catalogJanitorSwitch(true);
+    }
+  }
+
   // ==========================================================================
   //  Helpers
   // ==========================================================================
@@ -266,4 +321,9 @@ public class TestCloneSnapshotFromClient {
       long expectedRows) throws IOException {
     SnapshotTestingUtils.verifyRowCount(util, tableName, expectedRows);
   }
+
+  protected void splitRegion(final RegionInfo regionInfo) throws IOException {
+    byte[][] splitPoints = Bytes.split(regionInfo.getStartKey(), regionInfo.getEndKey(), 1);
+    admin.split(regionInfo.getTable(), splitPoints[1]);
+  }
 }