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 * 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
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package org.apache.hadoop.hbase.master;

import static org.junit.jupiter.api.Assertions.assertEquals;

import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.hadoop.hbase.HBaseTestingUtility;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.MiniHBaseCluster;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.StartMiniClusterOption;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.master.hbck.HbckChore;
import org.apache.hadoop.hbase.master.hbck.HbckReport;
import org.apache.hadoop.hbase.regionserver.HRegion;
import org.apache.hadoop.hbase.regionserver.HRegionServer;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.apache.hadoop.hbase.shaded.protobuf.generated.ProcedureProtos;

public abstract class AbstractTestMasterRegionMutation {

  private static final Logger LOG = LoggerFactory.getLogger(AbstractTestMasterRegionMutation.class);

  protected static final HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
  protected static ServerName rs0;

  protected static final AtomicBoolean ERROR_OUT = new AtomicBoolean(false);
  protected static final AtomicInteger ERROR_COUNTER = new AtomicInteger(0);
  protected static final AtomicBoolean FIRST_TIME_ERROR = new AtomicBoolean(true);

  protected static void setUpBeforeClass(int numMasters, Class<? extends HRegion> regionImplClass)
    throws Exception {
    TEST_UTIL.getConfiguration().setClass(HConstants.REGION_IMPL, regionImplClass, HRegion.class);
    StartMiniClusterOption.Builder builder = StartMiniClusterOption.builder();
    builder.numMasters(numMasters).numRegionServers(3);
    TEST_UTIL.startMiniCluster(builder.build());
    MiniHBaseCluster cluster = TEST_UTIL.getHBaseCluster();
    rs0 = cluster.getRegionServer(0).getServerName();
    TEST_UTIL.getAdmin().balancerSwitch(false, true);
  }

  protected static void tearDownAfterClass() throws Exception {
    TEST_UTIL.shutdownMiniCluster();
  }

  @BeforeEach
  public void setUp(TestInfo testInfo) throws Exception {
    final TableName tableName = TableName.valueOf(testInfo.getTestMethod().get().getName());
    TableDescriptor tableDesc = TableDescriptorBuilder.newBuilder(tableName)
      .setColumnFamily(ColumnFamilyDescriptorBuilder.of("fam1")).build();
    int startKey = 0;
    int endKey = 80000;
    TEST_UTIL.getAdmin().createTable(tableDesc, Bytes.toBytes(startKey), Bytes.toBytes(endKey), 9);
  }

  @Test
  public void testMasterRegionMutations() throws Exception {
    HbckChore hbckChore = new HbckChore(TEST_UTIL.getHBaseCluster().getMaster());
    MiniHBaseCluster cluster = TEST_UTIL.getHBaseCluster();

    HRegionServer hRegionServer0 = cluster.getRegionServer(0);
    HRegionServer hRegionServer1 = cluster.getRegionServer(1);
    HRegionServer hRegionServer2 = cluster.getRegionServer(2);
    int numRegions0 = hRegionServer0.getNumberOfOnlineRegions();
    int numRegions1 = hRegionServer1.getNumberOfOnlineRegions();
    int numRegions2 = hRegionServer2.getNumberOfOnlineRegions();

    hbckChore.choreForTesting();
    HbckReport hbckReport = hbckChore.getLastReport();
    assertEquals(0, hbckReport.getInconsistentRegions().size());
    assertEquals(0, hbckReport.getOrphanRegionsOnFS().size());
    assertEquals(0, hbckReport.getOrphanRegionsOnRS().size());

    // procedure state store update encounters retriable error, master abort is not required
    ERROR_OUT.set(true);

    // move one region from server 1 to server 0
    TEST_UTIL.getAdmin()
      .move(hRegionServer1.getRegions().get(0).getRegionInfo().getEncodedNameAsBytes(), rs0);

    // procedure state store update encounters retriable error, however all retries are exhausted.
    // This leads to the trigger of active master abort and hence master failover.
    ERROR_OUT.set(true);

    // move one region from server 2 to server 0
    TEST_UTIL.getAdmin()
      .move(hRegionServer2.getRegions().get(0).getRegionInfo().getEncodedNameAsBytes(), rs0);

    HMaster master = TEST_UTIL.getHBaseCluster().getMaster();

    // Ensure:
    // 1. num of regions before and after master abort remain same
    // 2. all procedures are successfully completed
    TEST_UTIL.waitFor(5000, 1000, () -> {
      LOG.info("numRegions0: {} , numRegions1: {} , numRegions2: {}", numRegions0, numRegions1,
        numRegions2);
      LOG.info("Online regions - server0 : {} , server1: {} , server2: {}",
        cluster.getRegionServer(0).getNumberOfOnlineRegions(),
        cluster.getRegionServer(1).getNumberOfOnlineRegions(),
        cluster.getRegionServer(2).getNumberOfOnlineRegions());
      LOG.info("Num of successfully completed procedures: {} , num of all procedures: {}",
        master.getMasterProcedureExecutor().getProcedures().stream()
          .filter(masterProcedureEnvProcedure -> masterProcedureEnvProcedure.getState()
              == ProcedureProtos.ProcedureState.SUCCESS)
          .count(),
        master.getMasterProcedureExecutor().getProcedures().size());
      return (numRegions0 + numRegions1 + numRegions2)
          == (cluster.getRegionServer(0).getNumberOfOnlineRegions()
            + cluster.getRegionServer(1).getNumberOfOnlineRegions()
            + cluster.getRegionServer(2).getNumberOfOnlineRegions())
        && master.getMasterProcedureExecutor().getProcedures().stream()
          .filter(masterProcedureEnvProcedure -> masterProcedureEnvProcedure.getState()
              == ProcedureProtos.ProcedureState.SUCCESS)
          .count() == master.getMasterProcedureExecutor().getProcedures().size();
    });

    // Ensure we have no inconsistent regions
    TEST_UTIL.waitFor(5000, 1000, () -> {
      HbckChore hbck = new HbckChore(TEST_UTIL.getHBaseCluster().getMaster());
      hbck.choreForTesting();
      HbckReport report = hbck.getLastReport();
      return report.getInconsistentRegions().isEmpty() && report.getOrphanRegionsOnFS().isEmpty()
        && report.getOrphanRegionsOnRS().isEmpty();
    });
  }
}
