/**
    * 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.snapshot;
  
  import static org.junit.Assert.assertFalse;
  
  import java.io.IOException;
  import java.util.Collection;
  import java.util.HashSet;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.HRegionInfo;
  import org.apache.hadoop.hbase.snapshot.SnapshotReferenceUtil;
  import org.apache.hadoop.hbase.snapshot.SnapshotTestingUtils;
  import org.apache.hadoop.hbase.testclassification.SmallTests;
  import org.apache.hadoop.hbase.snapshot.SnapshotDescriptionUtils;
  import org.apache.hadoop.hbase.util.FSUtils;
  import org.junit.AfterClass;
  import org.junit.BeforeClass;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  
  /**
   * Test that the snapshot hfile cleaner finds hfiles referenced in a snapshot
   */
  @Category(SmallTests.class)
  public class TestSnapshotHFileCleaner {
  
    private static final Log LOG = LogFactory.getLog(TestSnapshotFileCache.class);
    private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
    private static final String TABLE_NAME_STR = "testSnapshotManifest";
    private static final String SNAPSHOT_NAME_STR = "testSnapshotManifest-snapshot";
    private static Path rootDir;
    private static FileSystem fs;
  
    /**
     * Setup the test environment
     */
    @BeforeClass
    public static void setup() throws Exception {
      Configuration conf = TEST_UTIL.getConfiguration();
      rootDir = FSUtils.getRootDir(conf);
      fs = FileSystem.get(conf);
    }
  
    @AfterClass
    public static void cleanup() throws IOException {
      // cleanup
      fs.delete(rootDir, true);
    }
  
    @Test
    public void testFindsSnapshotFilesWhenCleaning() throws IOException {
      Configuration conf = TEST_UTIL.getConfiguration();
      FSUtils.setRootDir(conf, TEST_UTIL.getDataTestDir());
      Path rootDir = FSUtils.getRootDir(conf);
      Path archivedHfileDir = new Path(TEST_UTIL.getDataTestDir(), HConstants.HFILE_ARCHIVE_DIRECTORY);
  
      FileSystem fs = FileSystem.get(conf);
      SnapshotHFileCleaner cleaner = new SnapshotHFileCleaner();
      cleaner.setConf(conf);
  
      // write an hfile to the snapshot directory
      String snapshotName = "snapshot";
      TableName tableName = TableName.valueOf("table");
      Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, rootDir);
      HRegionInfo mockRegion = new HRegionInfo(tableName);
      Path regionSnapshotDir = new Path(snapshotDir, mockRegion.getEncodedName());
      Path familyDir = new Path(regionSnapshotDir, "family");
      // create a reference to a supposedly valid hfile
      String hfile = "fd1e73e8a96c486090c5cec07b4894c4";
      Path refFile = new Path(familyDir, hfile);
  
      // make sure the reference file exists
      fs.create(refFile);
  
      // create the hfile in the archive
     fs.mkdirs(archivedHfileDir);
     fs.createNewFile(new Path(archivedHfileDir, hfile));
 
     // make sure that the file isn't deletable
     assertFalse(cleaner.isFileDeletable(fs.getFileStatus(refFile)));
   }
 
   class SnapshotFiles implements SnapshotFileCache.SnapshotFileInspector {
     public Collection<String> filesUnderSnapshot(final Path snapshotDir) throws IOException {
       Collection<String> files =  new HashSet<String>();
       files.addAll(SnapshotReferenceUtil.getHFileNames(TEST_UTIL.getConfiguration(), fs, snapshotDir));
       return files;
     }
   }
 
   /**
    * If there is a corrupted region manifest, it should throw out CorruptedSnapshotException,
    * instead of an IOException
    */
   @Test
   public void testCorruptedRegionManifest() throws IOException {
     SnapshotTestingUtils.SnapshotMock
         snapshotMock = new SnapshotTestingUtils.SnapshotMock(TEST_UTIL.getConfiguration(), fs, rootDir);
     SnapshotTestingUtils.SnapshotMock.SnapshotBuilder builder = snapshotMock.createSnapshotV2(
         SNAPSHOT_NAME_STR, TABLE_NAME_STR);
     builder.addRegionV2();
     builder.corruptOneRegionManifest();
 
     fs.delete(SnapshotDescriptionUtils.getWorkingSnapshotDir(rootDir), true);
   }
 
   /**
    * If there is a corrupted data manifest, it should throw out CorruptedSnapshotException,
    * instead of an IOException
    */
   @Test
   public void testCorruptedDataManifest() throws IOException {
     SnapshotTestingUtils.SnapshotMock
         snapshotMock = new SnapshotTestingUtils.SnapshotMock(TEST_UTIL.getConfiguration(), fs, rootDir);
     SnapshotTestingUtils.SnapshotMock.SnapshotBuilder builder = snapshotMock.createSnapshotV2(
         SNAPSHOT_NAME_STR, TABLE_NAME_STR);
     builder.addRegionV2();
     // consolidate to generate a data.manifest file
     builder.consolidate();
     builder.corruptDataManifest();
 
     fs.delete(SnapshotDescriptionUtils.getWorkingSnapshotDir(rootDir), true);
   }
 }