CheckIndicesOperation.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.operation.master;

import java.util.List;

import net.sf.katta.master.MasterContext;
import net.sf.katta.operation.OperationId;
import net.sf.katta.operation.node.OperationResult;
import net.sf.katta.protocol.InteractionProtocol;
import net.sf.katta.protocol.metadata.IndexDeployError;
import net.sf.katta.protocol.metadata.IndexMetaData;
import net.sf.katta.protocol.metadata.IndexDeployError.ErrorType;

public class CheckIndicesOperation extends AbstractIndexOperation {

  private static final long serialVersionUID = 1L;

  @Override
  public List<OperationId> execute(MasterContext context, List<MasterOperation> runningOperations) throws Exception {
    InteractionProtocol protocol = context.getProtocol();
    List<String> liveNodes = protocol.getLiveNodes();
    List<String> indices = protocol.getIndices();

    for (String indexName : indices) {
      IndexMetaData indexMD = protocol.getIndexMD(indexName);
      if (indexMD != null) { // can be removed already
        if ((indexMD.hasDeployError() && isRecoverable(indexMD.getDeployError(), liveNodes.size()))
                || canAndShouldRegulateReplication(protocol, indexMD)) {
          protocol.addMasterOperation(new BalanceIndexOperation(indexName));
        }
      }
    }
    return null;
  }

  private boolean isRecoverable(IndexDeployError deployError, int nodeCount) {
    if (deployError.getErrorType() == ErrorType.NO_NODES_AVAILIBLE && nodeCount > 0) {
      return true;
    }
    return false;
  }

  @Override
  public void nodeOperationsComplete(MasterContext context, List<OperationResult> results) throws Exception {
    // nothing to do
  }

  @Override
  public ExecutionInstruction getExecutionInstruction(List<MasterOperation> runningOperations) throws Exception {
    for (MasterOperation operation : runningOperations) {
      if (operation instanceof CheckIndicesOperation) {
        return ExecutionInstruction.ADD_TO_QUEUE_TAIL;
      }
    }
    return ExecutionInstruction.EXECUTE;
  }

  @Override
  public String toString() {
    return getClass().getSimpleName() + ":" + Integer.toHexString(hashCode());
  }
}