/**
    * 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.regionserver;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  import static org.mockito.Mockito.mock;
  import static org.mockito.Mockito.when;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.Cell;
  import org.apache.hadoop.hbase.CellUtil;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HColumnDescriptor;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.HRegionInfo;
  import org.apache.hadoop.hbase.HTableDescriptor;
  import org.apache.hadoop.hbase.testclassification.SmallTests;
  import org.apache.hadoop.hbase.Stoppable;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.Durability;
  import org.apache.hadoop.hbase.client.Get;
  import org.apache.hadoop.hbase.client.Put;
  import org.apache.hadoop.hbase.client.Result;
  import org.apache.hadoop.hbase.wal.WALFactory;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.util.FSUtils;
  import org.apache.hadoop.hbase.util.StoppableImplementation;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  
  @Category(SmallTests.class)
  public class TestStoreFileRefresherChore {
  
    private HBaseTestingUtility TEST_UTIL;
    private Path testDir;
  
    @Before
    public void setUp() throws IOException {
      TEST_UTIL = new HBaseTestingUtility();
      testDir = TEST_UTIL.getDataTestDir("TestStoreFileRefresherChore");
      FSUtils.setRootDir(TEST_UTIL.getConfiguration(), testDir);
    }
  
    private HTableDescriptor getTableDesc(TableName tableName, byte[]... families) {
      HTableDescriptor htd = new HTableDescriptor(tableName);
      for (byte[] family : families) {
        HColumnDescriptor hcd = new HColumnDescriptor(family);
        // Set default to be three versions.
        hcd.setMaxVersions(Integer.MAX_VALUE);
        htd.addFamily(hcd);
      }
      return htd;
    }
  
    static class FailingHRegionFileSystem extends HRegionFileSystem {
      boolean fail = false;
      FailingHRegionFileSystem(Configuration conf, FileSystem fs, Path tableDir, HRegionInfo regionInfo) {
        super(conf, fs, tableDir, regionInfo);
      }
  
      @Override
      public Collection<StoreFileInfo> getStoreFiles(String familyName) throws IOException {
        if (fail) {
          throw new IOException("simulating FS failure");
        }
        return super.getStoreFiles(familyName);
      }
    }
  
    private Region initHRegion(HTableDescriptor htd, byte[] startKey, byte[] stopKey, int replicaId)
        throws IOException {
      Configuration conf = TEST_UTIL.getConfiguration();
      Path tableDir = FSUtils.getTableDir(testDir, htd.getTableName());
 
     HRegionInfo info = new HRegionInfo(htd.getTableName(), startKey, stopKey, false, 0, replicaId);
 
     HRegionFileSystem fs = new FailingHRegionFileSystem(conf, tableDir.getFileSystem(conf), tableDir,
       info);
     final Configuration walConf = new Configuration(conf);
     FSUtils.setRootDir(walConf, tableDir);
     final WALFactory wals = new WALFactory(walConf, null, "log_" + replicaId);
     HRegion region =
         new HRegion(fs, wals.getWAL(info.getEncodedNameAsBytes(), info.getTable().getNamespace()),
             conf, htd, null);
 
     region.initialize();
 
     return region;
   }
 
   private void putData(Region region, int startRow, int numRows, byte[] qf, byte[]... families)
       throws IOException {
     for (int i = startRow; i < startRow + numRows; i++) {
       Put put = new Put(Bytes.toBytes("" + i));
       put.setDurability(Durability.SKIP_WAL);
       for (byte[] family : families) {
         put.add(family, qf, null);
       }
       region.put(put);
     }
   }
 
   private void verifyDataExpectFail(Region newReg, int startRow, int numRows, byte[] qf,
       byte[]... families) throws IOException {
     boolean threw = false;
     try {
       verifyData(newReg, startRow, numRows, qf, families);
     } catch (AssertionError e) {
       threw = true;
     }
     if (!threw) {
       fail("Expected data verification to fail");
     }
   }
 
   private void verifyData(Region newReg, int startRow, int numRows, byte[] qf, byte[]... families)
       throws IOException {
     for (int i = startRow; i < startRow + numRows; i++) {
       byte[] row = Bytes.toBytes("" + i);
       Get get = new Get(row);
       for (byte[] family : families) {
         get.addColumn(family, qf);
       }
       Result result = newReg.get(get);
       Cell[] raw = result.rawCells();
       assertEquals(families.length, result.size());
       for (int j = 0; j < families.length; j++) {
         assertTrue(CellUtil.matchingRow(raw[j], row));
         assertTrue(CellUtil.matchingFamily(raw[j], families[j]));
         assertTrue(CellUtil.matchingQualifier(raw[j], qf));
       }
     }
   }
 
   static class StaleStorefileRefresherChore extends StorefileRefresherChore {
     boolean isStale = false;
     public StaleStorefileRefresherChore(int period, HRegionServer regionServer,
         Stoppable stoppable) {
       super(period, false, regionServer, stoppable);
     }
     @Override
     protected boolean isRegionStale(String encodedName, long time) {
       return isStale;
     }
   }
 
   @Test
   public void testIsStale() throws IOException {
     int period = 0;
     byte[][] families = new byte[][] {Bytes.toBytes("cf")};
     byte[] qf = Bytes.toBytes("cq");
 
     HRegionServer regionServer = mock(HRegionServer.class);
     List<Region> regions = new ArrayList<Region>();
     when(regionServer.getOnlineRegionsLocalContext()).thenReturn(regions);
     when(regionServer.getConfiguration()).thenReturn(TEST_UTIL.getConfiguration());
 
     HTableDescriptor htd = getTableDesc(TableName.valueOf("testIsStale"), families);
     htd.setRegionReplication(2);
 
     Region primary = initHRegion(htd, HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW, 0);
     Region replica1 = initHRegion(htd, HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW, 1);
     regions.add(primary);
     regions.add(replica1);
 
     StaleStorefileRefresherChore chore = new StaleStorefileRefresherChore(period, regionServer, new StoppableImplementation());
 
     // write some data to primary and flush
     putData(primary, 0, 100, qf, families);
     primary.flush(true);
     verifyData(primary, 0, 100, qf, families);
 
     verifyDataExpectFail(replica1, 0, 100, qf, families);
     chore.chore();
     verifyData(replica1, 0, 100, qf, families);
 
     // simulate an fs failure where we cannot refresh the store files for the replica
     ((FailingHRegionFileSystem)((HRegion)replica1).getRegionFileSystem()).fail = true;
 
     // write some more data to primary and flush
     putData(primary, 100, 100, qf, families);
     primary.flush(true);
     verifyData(primary, 0, 200, qf, families);
 
     chore.chore(); // should not throw ex, but we cannot refresh the store files
 
     verifyData(replica1, 0, 100, qf, families);
     verifyDataExpectFail(replica1, 100, 100, qf, families);
 
     chore.isStale = true;
     chore.chore(); //now after this, we cannot read back any value
     try {
       verifyData(replica1, 0, 100, qf, families);
       fail("should have failed with IOException");
     } catch(IOException ex) {
       // expected
     }
   }
 }