content: /*
   * 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.asterix.external.util;
  
  import java.net.InetAddress;
  import java.net.UnknownHostException;
  import java.util.Map;
  import java.util.Random;
  import java.util.Set;
  
  import org.apache.asterix.common.dataflow.ICcApplicationContext;
  import org.apache.asterix.common.exceptions.AsterixException;
  import org.apache.asterix.common.exceptions.ErrorCode;
  import org.apache.asterix.external.api.INodeResolver;
  
  /**
   * Resolves a value (DNS/IP Address) or a (Node Controller Id) to the id of a Node Controller running at the location.
   */
  public class NodeResolver implements INodeResolver {
      //TODO: change this call and replace by calling AsterixClusterProperties
      private final Random random = new Random();
  
      @Override
      public String resolveNode(ICcApplicationContext appCtx, String value, Map<InetAddress, Set<String>> ncMap,
              Set<String> ncs) throws AsterixException {
          if (ncs.contains(value)) {
              return value;
          }
          InetAddress ipAddress = null;
          try {
              ipAddress = InetAddress.getByName(value);
          } catch (UnknownHostException e) {
              throw new AsterixException(ErrorCode.NODE_RESOLVER_UNABLE_RESOLVE_HOST, e, value);
          }
          Set<String> nodeControllers = ncMap.get(ipAddress);
          if (nodeControllers == null || nodeControllers.isEmpty()) {
              throw new AsterixException(ErrorCode.NODE_RESOLVER_NO_NODE_CONTROLLERS, value);
          }
          return nodeControllers.toArray(new String[] {})[random.nextInt(nodeControllers.size())];
      }
  }
  