org.apache.hadoop.hbase.snapshot.SnapshotDescriptionUtils#getWorkingSnapshotDir ( )源码实例Demo

/**
 * Take a snapshot using the specified handler.
 * On failure the snapshot temporary working directory is removed.
 * NOTE: prepareToTakeSnapshot() called before this one takes care of the rejecting the
 *       snapshot request if the table is busy with another snapshot/restore operation.
 * @param snapshot the snapshot description
 * @param handler the snapshot handler
 */
private synchronized void snapshotTable(SnapshotDescription snapshot,
    final TakeSnapshotHandler handler) throws IOException {
  try {
    handler.prepare();
    this.executorService.submit(handler);
    this.snapshotHandlers.put(TableName.valueOf(snapshot.getTable()), handler);
  } catch (Exception e) {
    // cleanup the working directory by trying to delete it from the fs.
    Path workingDir = SnapshotDescriptionUtils.getWorkingSnapshotDir(snapshot, rootDir,
        master.getConfiguration());
    FileSystem workingDirFs = workingDir.getFileSystem(master.getConfiguration());
    try {
      if (!workingDirFs.delete(workingDir, true)) {
        LOG.error("Couldn't delete working directory (" + workingDir + " for snapshot:" +
            ClientSnapshotDescriptionUtils.toString(snapshot));
      }
    } catch (IOException e1) {
      LOG.error("Couldn't delete working directory (" + workingDir + " for snapshot:" +
          ClientSnapshotDescriptionUtils.toString(snapshot));
    }
    // fail the snapshot
    throw new SnapshotCreationException("Could not build snapshot handler", e,
      ProtobufUtil.createSnapshotDesc(snapshot));
  }
}
 

@Override
public void setConf(final Configuration conf) {
  super.setConf(conf);
  try {
    long cacheRefreshPeriod = conf.getLong(HFILE_CACHE_REFRESH_PERIOD_CONF_KEY,
      DEFAULT_HFILE_CACHE_REFRESH_PERIOD);
    final FileSystem fs = CommonFSUtils.getCurrentFileSystem(conf);
    Path rootDir = CommonFSUtils.getRootDir(conf);
    Path workingDir = SnapshotDescriptionUtils.getWorkingSnapshotDir(rootDir, conf);
    FileSystem workingFs = workingDir.getFileSystem(conf);

    cache = new SnapshotFileCache(fs, rootDir, workingFs, workingDir, cacheRefreshPeriod,
      cacheRefreshPeriod, "snapshot-hfile-cleaner-cache-refresher",
      new SnapshotFileCache.SnapshotFileInspector() {
          @Override
          public Collection<String> filesUnderSnapshot(final FileSystem fs,
            final Path snapshotDir)
              throws IOException {
            return SnapshotReferenceUtil.getHFileNames(conf, fs, snapshotDir);
          }
        });
  } catch (IOException e) {
    LOG.error("Failed to create cleaner util", e);
  }
}
 

/**
 * Cleans up any snapshots in the snapshot/.tmp directory that were left from failed
 * snapshot attempts.
 *
 * @throws IOException if we can't reach the filesystem
 */
private void resetTempDir() throws IOException {
  // cleanup any existing snapshots.
  Path tmpdir = SnapshotDescriptionUtils.getWorkingSnapshotDir(rootDir,
      master.getConfiguration());
  FileSystem tmpFs = tmpdir.getFileSystem(master.getConfiguration());
  if (!tmpFs.delete(tmpdir, true)) {
    LOG.warn("Couldn't delete working snapshot directory: " + tmpdir);
  }
}
 

@BeforeClass
public static void startCluster() throws Exception {
  initCommon();

  // Set the snapshot working directory to be on another filesystem.
  conf.set(SnapshotDescriptionUtils.SNAPSHOT_WORKING_DIR,
    "file://" + new Path(TEMP_DIR, ".tmpDir").toUri());
  workingDir = SnapshotDescriptionUtils.getWorkingSnapshotDir(rootDir, conf);
  workingFs = workingDir.getFileSystem(conf);
}
 

@BeforeClass
public static void startCluster() throws Exception {
  initCommon();
  workingDir = SnapshotDescriptionUtils.getWorkingSnapshotDir(rootDir, conf);
  workingFs = workingDir.getFileSystem(conf);
}
 

/**
 * Create a snapshot file cache for all snapshots under the specified [root]/.snapshot on the
 * filesystem.
 * <p>
 * Immediately loads the file cache.
 * @param conf to extract the configured {@link FileSystem} where the snapshots are stored and
 *          hbase root directory
 * @param cacheRefreshPeriod frequency (ms) with which the cache should be refreshed
 * @param cacheRefreshDelay amount of time to wait for the cache to be refreshed
 * @param refreshThreadName name of the cache refresh thread
 * @param inspectSnapshotFiles Filter to apply to each snapshot to extract the files.
 * @throws IOException if the {@link FileSystem} or root directory cannot be loaded
 */
public SnapshotFileCache(Configuration conf, long cacheRefreshPeriod, long cacheRefreshDelay,
  String refreshThreadName, SnapshotFileInspector inspectSnapshotFiles) throws IOException {
  this(CommonFSUtils.getCurrentFileSystem(conf), CommonFSUtils.getRootDir(conf),
    SnapshotDescriptionUtils.getWorkingSnapshotDir(CommonFSUtils.getRootDir(conf), conf).
      getFileSystem(conf),
    SnapshotDescriptionUtils.getWorkingSnapshotDir(CommonFSUtils.getRootDir(conf), conf),
    cacheRefreshPeriod, cacheRefreshDelay, refreshThreadName, inspectSnapshotFiles);
}