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.ambari.server.checks;
  
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Set;
  
  import org.apache.ambari.annotations.UpgradeCheckInfo;
  import org.apache.ambari.server.AmbariException;
  import org.apache.ambari.server.state.ConfigMergeHelper;
  import org.apache.ambari.server.state.ConfigMergeHelper.ThreeWayValue;
  import org.apache.ambari.server.state.StackId;
  import org.apache.ambari.spi.RepositoryVersion;
  import org.apache.ambari.spi.upgrade.UpgradeCheckDescription;
  import org.apache.ambari.spi.upgrade.UpgradeCheckRequest;
  import org.apache.ambari.spi.upgrade.UpgradeCheckResult;
  import org.apache.ambari.spi.upgrade.UpgradeCheckStatus;
  import org.apache.ambari.spi.upgrade.UpgradeCheckType;
  import org.apache.ambari.spi.upgrade.UpgradeType;
  import org.apache.commons.lang.StringUtils;
  
  import com.google.common.collect.ImmutableMap;
  import com.google.inject.Inject;
  import com.google.inject.Singleton;
  
  /**
   * Checks for configuration merge conflicts.
   */
  @Singleton
  @UpgradeCheckInfo(
      order = 99.0f,
      required = { UpgradeType.ROLLING, UpgradeType.NON_ROLLING, UpgradeType.HOST_ORDERED })
  public class ConfigurationMergeCheck extends ClusterCheck {
  
    @Inject
    ConfigMergeHelper m_mergeHelper;
  
    static final UpgradeCheckDescription CONFIG_MERGE = new UpgradeCheckDescription("CONFIG_MERGE",
        UpgradeCheckType.CLUSTER,
        "Configuration Merge Check",
        new ImmutableMap.Builder<String, String>()
          .put(UpgradeCheckDescription.DEFAULT,
              "The following config types will have values overwritten: %s").build());
  
    public ConfigurationMergeCheck() {
      super(CONFIG_MERGE);
    }
  
    /**
     * The following logic determines if a warning is generated for config merge
     * issues:
     * <ul>
     *   <li>A value that has been customized from HDP 2.2.x.x no longer exists in HDP 2.3.x.x</li>
     *   <li>A value that has been customized from HDP 2.2.x.x has changed its default value between HDP 2.2.x.x and HDP 2.3.x.x</li>
     * </ul>
     */
    @Override
    public UpgradeCheckResult perform(UpgradeCheckRequest request)
        throws AmbariException {
      UpgradeCheckResult result = new UpgradeCheckResult(this);
  
      RepositoryVersion repositoryVersion = request.getTargetRepositoryVersion();
  
      Map<String, Map<String, ThreeWayValue>> changes = m_mergeHelper.getConflicts(
          request.getClusterName(), new StackId(repositoryVersion.getStackId()));
  
      Set<String> failedTypes = new HashSet<>();
  
      for (Entry<String, Map<String, ThreeWayValue>> entry : changes.entrySet()) {
        for (Entry<String, ThreeWayValue> configEntry : entry.getValue().entrySet()) {
  
          ThreeWayValue twv = configEntry.getValue();
          if (null == twv.oldStackValue) { // !!! did not exist and in the map means changed
            failedTypes.add(entry.getKey());
  
            result.getFailedOn().add(entry.getKey() + "/" + configEntry.getKey());
  
            MergeDetail md = new MergeDetail();
            md.type = entry.getKey();
            md.property = configEntry.getKey();
            md.current = twv.savedValue;
            md.new_stack_value = twv.newStackValue;
            md.result_value = md.current;
            result.getFailedDetail().add(md);
  
          } else if (!twv.oldStackValue.equals(twv.savedValue)) {  // !!! value customized
            if (null == twv.newStackValue || // !!! not in new stack
                !twv.oldStackValue.equals(twv.newStackValue)) { // !!! or the default value changed
              failedTypes.add(entry.getKey());
  
              result.getFailedOn().add(entry.getKey() + "/" + configEntry.getKey());
  
              MergeDetail md = new MergeDetail();
              md.type = entry.getKey();
              md.property = configEntry.getKey();
              md.current = twv.savedValue;
              md.new_stack_value = twv.newStackValue;
              md.result_value = md.current;
              result.getFailedDetail().add(md);
            }
          }
        }
      }
  
      if (result.getFailedOn().size() > 0) {
        result.setStatus(UpgradeCheckStatus.WARNING);
        String failReason = getFailReason(result, request);
  
        result.setFailReason(String.format(failReason, StringUtils.join(
            failedTypes, ", ")));
  
      } else {
        result.setStatus(UpgradeCheckStatus.PASS);
      }
  
      return result;
    }
  
    /**
     * Used to represent specific detail about merge failures.
     */
    public static class MergeDetail {
      public String type = null;
      public String property = null;
      public String current = null;
      public String new_stack_value = null;
      public String result_value = null;
    }
  
  }
  