/**
* Copyright (C) 2012 LinkedIn Inc <opensource@linkedin.com>
*
* 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 com.linkedin.helix.controller.stages;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.log4j.Logger;
import com.linkedin.helix.HelixDataAccessor;
import com.linkedin.helix.HelixManager;
import com.linkedin.helix.PropertyKey;
import com.linkedin.helix.controller.pipeline.AbstractBaseStage;
import com.linkedin.helix.controller.pipeline.StageException;
import com.linkedin.helix.model.ExternalView;
import com.linkedin.helix.model.Partition;
import com.linkedin.helix.model.Resource;
import com.linkedin.helix.monitoring.mbeans.ClusterStatusMonitor;
public class ExternalViewComputeStage extends AbstractBaseStage
{
private static Logger log = Logger.getLogger(ExternalViewComputeStage.class);
@Override
public void process(ClusterEvent event) throws Exception
{
long startTime = System.currentTimeMillis();
log.info("START ExternalViewComputeStage.process()");
HelixManager manager = event.getAttribute("helixmanager");
Map<String, Resource> resourceMap =
event.getAttribute(AttributeName.RESOURCES.toString());
ClusterDataCache cache = event.getAttribute("ClusterDataCache");
if (manager == null || resourceMap == null || cache == null)
{
throw new StageException("Missing attributes in event:" + event
+ ". Requires ClusterManager|RESOURCES|DataCache");
}
HelixDataAccessor dataAccessor = manager.getHelixDataAccessor();
CurrentStateOutput currentStateOutput =
event.getAttribute(AttributeName.CURRENT_STATE.toString());
List<ExternalView> newExtViews = new ArrayList<ExternalView>();
List<PropertyKey> keys = new ArrayList<PropertyKey>();
for (String resourceName : resourceMap.keySet())
{
ExternalView view = new ExternalView(resourceName);
// if resource ideal state has bucket size, set it
// otherwise resource has been dropped, use bucket size from current state instead
Resource resource = resourceMap.get(resourceName);
if (resource.getBucketSize() > 0)
{
view.setBucketSize(resource.getBucketSize());
} else
{
view.setBucketSize(currentStateOutput.getBucketSize(resourceName));
}
for (Partition partition : resource.getPartitions())
{
Map<String, String> currentStateMap =
currentStateOutput.getCurrentStateMap(resourceName, partition);
if (currentStateMap != null && currentStateMap.size() > 0)
{
// Set<String> disabledInstances
// = cache.getDisabledInstancesForResource(resource.toString());
for (String instance : currentStateMap.keySet())
{
// if (!disabledInstances.contains(instance))
// {
view.setState(partition.getPartitionName(),
instance,
currentStateMap.get(instance));
// }
}
}
}
// Update cluster status monitor mbean
ClusterStatusMonitor clusterStatusMonitor =
(ClusterStatusMonitor) event.getAttribute("clusterStatusMonitor");
if (clusterStatusMonitor != null)
{
clusterStatusMonitor.onExternalViewChange(view,
cache._idealStateMap.get(view.getResourceName()));
}
// compare the new external view with current one, set only on different
Map<String, ExternalView> curExtViews =
dataAccessor.getChildValuesMap(manager.getHelixDataAccessor()
.keyBuilder()
.externalViews());
ExternalView curExtView = curExtViews.get(resourceName);
if (curExtView == null || !curExtView.getRecord().equals(view.getRecord()))
{
keys.add(manager.getHelixDataAccessor().keyBuilder().externalView(resourceName));
newExtViews.add(view);
// dataAccessor.setProperty(PropertyType.EXTERNALVIEW, view,
// resourceName);
}
}
if (newExtViews.size() > 0)
{
dataAccessor.setChildren(keys, newExtViews);
}
long endTime = System.currentTimeMillis();
log.info("END ExternalViewComputeStage.process(). took: " + (endTime - startTime) + " ms");
}
}