UpgradeAction05_06.java

/**
 * Copyright 2008 the original author or authors.
 *
 * Licensed 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 net.sf.katta.protocol.upgrade;

import java.util.List;

import net.sf.katta.operation.master.IndexReinitializeOperation;
import net.sf.katta.protocol.InteractionProtocol;
import net.sf.katta.protocol.metadata.IndexMetaData;
import net.sf.katta.util.ZkConfiguration;

import org.I0Itec.zkclient.ZkClient;
import org.I0Itec.zkclient.exception.ZkMarshallingError;
import org.I0Itec.zkclient.serialize.ZkSerializer;
import org.apache.hadoop.io.DataInputBuffer;
import org.apache.hadoop.io.DataOutputBuffer;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.io.Writable;
import org.apache.log4j.Logger;

class UpgradeAction05_06 implements UpgradeAction {

  private static final Logger LOG = Logger.getLogger(UpgradeAction05_06.class);

  @SuppressWarnings("deprecation")
  @Override
  public void upgrade(InteractionProtocol protocol) {
    ZkClient zkClient = protocol.getZkClient();
    ZkConfiguration zkConf = protocol.getZkConfiguration();
    ZkClient zkClientForWriables = new ZkClient(zkConf.getZKServers(), 5000, 5000, new WriteableZkSerializer(
            net.sf.katta.index.IndexMetaData.class));
    LOG.info("restoring indices meta data...");
    String oldIndicesPath = getOldIndicesPath(zkConf);
    List<String> indices = zkClient.getChildren(oldIndicesPath);
    LOG.info("found " + indices.size() + " old indices");
    for (String indexName : indices) {
      net.sf.katta.index.IndexMetaData oldIndexMD = zkClientForWriables.readData(oldIndicesPath + "/" + indexName);
      IndexMetaData newIndexMD = new IndexMetaData(indexName, oldIndexMD.getPath(), oldIndexMD.getReplicationLevel());
      IndexReinitializeOperation deployOperation = new IndexReinitializeOperation(newIndexMD);
      protocol.addMasterOperation(deployOperation);
      protocol.publishIndex(newIndexMD);
    }
    zkClientForWriables.close();

    LOG.info("deleting obsolete folders...");
    zkClient.deleteRecursive(zkConf.getZkRootPath() + "/" + "indexes");
    zkClient.deleteRecursive(zkConf.getZkRootPath() + "/" + "node-to-shard");
    zkClient.deleteRecursive(zkConf.getZkRootPath() + "/" + "shard-to-node");
    zkClient.deleteRecursive(zkConf.getZkRootPath() + "/" + "loadtest-nodes");
    zkClient.deleteRecursive(zkConf.getZkRootPath() + "/" + "server-metrics");
    zkClient.deleteRecursive(zkConf.getZkRootPath() + "/" + "shard-to-error");

    LOG.info("upgrade done");
  }

  protected static String getOldIndicesPath(ZkConfiguration zkConf) {
    return zkConf.getZkRootPath() + "/" + "indexes";
  }

  static class WriteableZkSerializer implements ZkSerializer {

    private final Class<? extends Writable> _writableClass;

    public WriteableZkSerializer(Class<? extends Writable> writableClass) {
      _writableClass = writableClass;
    }

    @Override
    public Object deserialize(byte[] bytes) throws ZkMarshallingError {
      DataInputBuffer buffer = new DataInputBuffer();
      buffer.reset(bytes, bytes.length);
      try {
        Writable instance = _writableClass.newInstance();
        instance.readFields(buffer);
        buffer.close();
        return instance;
      } catch (Exception e) {
        throw new ZkMarshallingError(e);
      }
    }

    @Override
    public byte[] serialize(Object data) throws ZkMarshallingError {
      DataOutputBuffer out = new DataOutputBuffer();
      try {
        ((Writable) data).write(out);
        return out.getData();
      } catch (Exception e) {
        throw new ZkMarshallingError(e);
      } finally {
        IOUtils.closeStream(out);
      }
    }

  }

}