Esempio n. 1
0
  public static void cloneTable(
      Instance instance, String srcTableId, String tableId, VolumeManager volumeManager)
      throws Exception {

    Connector conn =
        instance.getConnector(
            SystemCredentials.get().getPrincipal(), SystemCredentials.get().getToken());
    BatchWriter bw = conn.createBatchWriter(MetadataTable.NAME, new BatchWriterConfig());

    while (true) {

      try {
        initializeClone(srcTableId, tableId, conn, bw);

        // the following loop looks changes in the file that occurred during the copy.. if files
        // were dereferenced then they could have been GCed

        while (true) {
          int rewrites = checkClone(srcTableId, tableId, conn, bw);

          if (rewrites == 0) break;
        }

        bw.flush();
        break;

      } catch (TabletIterator.TabletDeletedException tde) {
        // tablets were merged in the src table
        bw.flush();

        // delete what we have cloned and try again
        deleteTable(tableId, false, SystemCredentials.get(), null);

        log.debug(
            "Tablets merged in table " + srcTableId + " while attempting to clone, trying again");

        UtilWaitThread.sleep(100);
      }
    }

    // delete the clone markers and create directory entries
    Scanner mscanner = conn.createScanner(MetadataTable.NAME, Authorizations.EMPTY);
    mscanner.setRange(new KeyExtent(new Text(tableId), null, null).toMetadataRange());
    mscanner.fetchColumnFamily(ClonedColumnFamily.NAME);

    int dirCount = 0;

    for (Entry<Key, Value> entry : mscanner) {
      Key k = entry.getKey();
      Mutation m = new Mutation(k.getRow());
      m.putDelete(k.getColumnFamily(), k.getColumnQualifier());
      String dir =
          volumeManager.choose(ServerConstants.getTablesDirs())
              + "/"
              + tableId
              + new String(FastFormat.toZeroPaddedString(dirCount++, 8, 16, "/c-".getBytes()));
      TabletsSection.ServerColumnFamily.DIRECTORY_COLUMN.put(m, new Value(dir.getBytes()));
      bw.addMutation(m);
    }

    bw.close();
  }