HBASE-23187 Update parent region state to SPLIT in meta (#732)

* HBASE-23187 Update parent region state to SPLIT in meta

hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/RegionStates.java

@@ -350,9 +350,13 @@ public class RegionStates {
     if (LOG.isTraceEnabled()) {
       LOG.trace("WORKING ON " + node + " " + node.getRegionInfo());
     }
-    if (node.isInState(State.SPLIT)) return false;
-    if (node.isInState(State.OFFLINE) && !offline) return false;
     final RegionInfo hri = node.getRegionInfo();
+    if (node.isInState(State.SPLIT) || hri.isSplit()) {
+      return false;
+    }
+    if ((node.isInState(State.OFFLINE) || hri.isOffline()) && !offline) {
+      return false;
+    }
     return (!hri.isOffline() && !hri.isSplit()) ||
         ((hri.isOffline() || hri.isSplit()) && offline);
   }

hbase-server/src/test/java/org/apache/hadoop/hbase/master/assignment/TestRegionSplit.java

@@ -0,0 +1,169 @@
+/**
+ * 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.hbase.master.assignment;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import java.io.IOException;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.HBaseClassTestRule;
+import org.apache.hadoop.hbase.HBaseTestingUtility;
+import org.apache.hadoop.hbase.StartMiniClusterOption;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.RegionInfo;
+import org.apache.hadoop.hbase.client.Table;
+import org.apache.hadoop.hbase.client.TableDescriptor;
+import org.apache.hadoop.hbase.master.procedure.MasterProcedureEnv;
+import org.apache.hadoop.hbase.master.procedure.MasterProcedureTestingUtility;
+import org.apache.hadoop.hbase.procedure2.ProcedureExecutor;
+import org.apache.hadoop.hbase.procedure2.ProcedureTestingUtility;
+import org.apache.hadoop.hbase.testclassification.LargeTests;
+import org.apache.hadoop.hbase.testclassification.MasterTests;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.util.JVMClusterUtil;
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.ClassRule;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+import org.junit.rules.TestName;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+@Category({MasterTests.class, LargeTests.class})
+public class TestRegionSplit {
+
+  @ClassRule
+  public static final HBaseClassTestRule CLASS_RULE =
+      HBaseClassTestRule.forClass(TestRegionSplit.class);
+
+  private static final Logger LOG = LoggerFactory.getLogger(TestRegionSplit.class);
+
+  protected static final HBaseTestingUtility UTIL = new HBaseTestingUtility();
+
+  private static String ColumnFamilyName = "cf";
+
+  private static final int startRowNum = 11;
+  private static final int rowCount = 60;
+
+  @Rule
+  public TestName name = new TestName();
+
+  private static void setupConf(Configuration conf) {
+  }
+
+  @BeforeClass
+  public static void setupCluster() throws Exception {
+    setupConf(UTIL.getConfiguration());
+    StartMiniClusterOption option =
+        StartMiniClusterOption.builder().numMasters(1).numRegionServers(3).numDataNodes(3).build();
+    UTIL.startMiniCluster(option);
+  }
+
+  @AfterClass
+  public static void cleanupTest() throws Exception {
+    try {
+      UTIL.shutdownMiniCluster();
+    } catch (Exception e) {
+      LOG.warn("failure shutting down cluster", e);
+    }
+  }
+
+  @Before
+  public void setup() throws Exception {
+    // Turn off the meta scanner so it don't remove parent on us.
+    UTIL.getHBaseCluster().getMaster().setCatalogJanitorEnabled(false);
+    // Disable compaction.
+    for (int i = 0; i < UTIL.getHBaseCluster().getLiveRegionServerThreads().size(); i++) {
+      UTIL.getHBaseCluster().getRegionServer(i).getCompactSplitThread().switchCompaction(false);
+    }
+  }
+
+  @After
+  public void tearDown() throws Exception {
+    for (TableDescriptor htd : UTIL.getAdmin().listTableDescriptors()) {
+      UTIL.deleteTable(htd.getTableName());
+    }
+  }
+
+  @Test
+  public void testSplitTableRegion() throws Exception {
+    final TableName tableName = TableName.valueOf(name.getMethodName());
+    final ProcedureExecutor<MasterProcedureEnv> procExec = getMasterProcedureExecutor();
+
+    RegionInfo[] regions =
+        MasterProcedureTestingUtility.createTable(procExec, tableName, null, ColumnFamilyName);
+    insertData(tableName);
+    int splitRowNum = startRowNum + rowCount / 2;
+    byte[] splitKey = Bytes.toBytes("" + splitRowNum);
+
+    assertTrue("not able to find a splittable region", regions != null);
+    assertTrue("not able to find a splittable region", regions.length == 1);
+
+    // Split region of the table
+    long procId = procExec.submitProcedure(
+        new SplitTableRegionProcedure(procExec.getEnvironment(), regions[0], splitKey));
+    // Wait the completion
+    ProcedureTestingUtility.waitProcedure(procExec, procId);
+    ProcedureTestingUtility.assertProcNotFailed(procExec, procId);
+
+    assertTrue("not able to split table", UTIL.getHBaseCluster().getRegions(tableName).size() == 2);
+
+    //disable table
+    UTIL.getAdmin().disableTable(tableName);
+    Thread.sleep(500);
+
+    //stop master
+    UTIL.getHBaseCluster().stopMaster(0);
+    UTIL.getHBaseCluster().waitOnMaster(0);
+    Thread.sleep(500);
+
+    //restart master
+    JVMClusterUtil.MasterThread t = UTIL.getHBaseCluster().startMaster();
+    Thread.sleep(500);
+
+    // enable table
+    UTIL.getAdmin().enableTable(tableName);
+    Thread.sleep(500);
+
+    assertEquals("Table region not correct.", 2,
+        UTIL.getHBaseCluster().getRegions(tableName).size());
+  }
+
+  private void insertData(final TableName tableName) throws IOException {
+    Table t = UTIL.getConnection().getTable(tableName);
+    Put p;
+    for (int i = 0; i < rowCount / 2; i++) {
+      p = new Put(Bytes.toBytes("" + (startRowNum + i)));
+      p.addColumn(Bytes.toBytes(ColumnFamilyName), Bytes.toBytes("q1"), Bytes.toBytes(i));
+      t.put(p);
+      p = new Put(Bytes.toBytes("" + (startRowNum + rowCount - i - 1)));
+      p.addColumn(Bytes.toBytes(ColumnFamilyName), Bytes.toBytes("q1"), Bytes.toBytes(i));
+      t.put(p);
+    }
+    UTIL.getAdmin().flush(tableName);
+  }
+
+  private ProcedureExecutor<MasterProcedureEnv> getMasterProcedureExecutor() {
+    return UTIL.getHBaseCluster().getMaster().getMasterProcedureExecutor();
+  }
+}