/**
* 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.webapp.resources;
import java.io.IOException;
import java.util.Map;
import org.apache.log4j.Logger;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.JsonMappingException;
import org.restlet.Context;
import org.restlet.data.MediaType;
import org.restlet.data.Request;
import org.restlet.data.Response;
import org.restlet.data.Status;
import org.restlet.resource.Representation;
import org.restlet.resource.Resource;
import org.restlet.resource.StringRepresentation;
import org.restlet.resource.Variant;
import com.linkedin.helix.HelixDataAccessor;
import com.linkedin.helix.HelixException;
import com.linkedin.helix.PropertyKey;
import com.linkedin.helix.PropertyKey.Builder;
import com.linkedin.helix.ZNRecord;
import com.linkedin.helix.manager.zk.ZkClient;
import com.linkedin.helix.model.IdealState;
import com.linkedin.helix.tools.ClusterSetup;
import com.linkedin.helix.webapp.RestAdminApplication;
public class IdealStateResource extends Resource
{
private final static Logger LOG = Logger.getLogger(IdealStateResource.class);
public IdealStateResource(Context context, Request request, Response response)
{
super(context, request, response);
getVariants().add(new Variant(MediaType.TEXT_PLAIN));
getVariants().add(new Variant(MediaType.APPLICATION_JSON));
}
@Override
public boolean allowGet()
{
return true;
}
@Override
public boolean allowPost()
{
return true;
}
@Override
public boolean allowPut()
{
return false;
}
@Override
public boolean allowDelete()
{
return false;
}
@Override
public Representation represent(Variant variant)
{
StringRepresentation presentation = null;
try
{
String clusterName = (String) getRequest().getAttributes().get("clusterName");
String resourceName = (String) getRequest().getAttributes().get("resourceName");
presentation = getIdealStateRepresentation(clusterName, resourceName);
}
catch (Exception e)
{
String error = ClusterRepresentationUtil.getErrorAsJsonStringFromException(e);
presentation = new StringRepresentation(error, MediaType.APPLICATION_JSON);
LOG.error("", e);
}
return presentation;
}
StringRepresentation getIdealStateRepresentation(String clusterName, String resourceName) throws JsonGenerationException,
JsonMappingException,
IOException
{
Builder keyBuilder = new PropertyKey.Builder(clusterName);
ZkClient zkClient =
(ZkClient) getContext().getAttributes().get(RestAdminApplication.ZKCLIENT);
String message =
ClusterRepresentationUtil.getClusterPropertyAsString(zkClient,
clusterName,
keyBuilder.idealStates(resourceName),
MediaType.APPLICATION_JSON);
StringRepresentation representation =
new StringRepresentation(message, MediaType.APPLICATION_JSON);
return representation;
}
@Override
public void acceptRepresentation(Representation entity)
{
try
{
String clusterName = (String) getRequest().getAttributes().get("clusterName");
String resourceName = (String) getRequest().getAttributes().get("resourceName");
ZkClient zkClient =
(ZkClient) getContext().getAttributes().get(RestAdminApplication.ZKCLIENT);
ClusterSetup setupTool = new ClusterSetup(zkClient);
JsonParameters jsonParameters = new JsonParameters(entity);
String command = jsonParameters.getCommand();
if (command.equalsIgnoreCase(ClusterSetup.addIdealState))
{
ZNRecord newIdealState = jsonParameters.getExtraParameter(JsonParameters.NEW_IDEAL_STATE);
HelixDataAccessor accessor =
ClusterRepresentationUtil.getClusterDataAccessor(zkClient, clusterName);
accessor.setProperty(accessor.keyBuilder().idealStates(resourceName),
new IdealState(newIdealState));
}
else if (command.equalsIgnoreCase(ClusterSetup.rebalance))
{
int replicas =
Integer.parseInt(jsonParameters.getParameter(JsonParameters.REPLICAS));
if (jsonParameters.getParameter(JsonParameters.RESOURCE_KEY_PREFIX) != null)
{
setupTool.rebalanceStorageCluster(clusterName,
resourceName,
replicas,
jsonParameters.getParameter(JsonParameters.RESOURCE_KEY_PREFIX));
}
else
{
setupTool.rebalanceStorageCluster(clusterName, resourceName, replicas);
}
}
else if (command.equalsIgnoreCase(ClusterSetup.expandResource))
{
setupTool.expandResource(clusterName, resourceName);
}
else if (command.equalsIgnoreCase(ClusterSetup.addResourceProperty))
{
Map<String, String> parameterMap = jsonParameters.cloneParameterMap();
parameterMap.remove(JsonParameters.MANAGEMENT_COMMAND);
for (String key : parameterMap.keySet())
{
setupTool.addResourceProperty(clusterName,
resourceName,
key,
parameterMap.get(key));
}
}
else
{
throw new HelixException("Unsupported command: " + command
+ ". Should be one of [" + ClusterSetup.addIdealState + ", "
+ ClusterSetup.rebalance + ", " + ClusterSetup.expandResource + ", "
+ ClusterSetup.addResourceProperty + "]");
}
getResponse().setEntity(getIdealStateRepresentation(clusterName, resourceName));
getResponse().setStatus(Status.SUCCESS_OK);
}
catch (Exception e)
{
getResponse().setEntity(ClusterRepresentationUtil.getErrorAsJsonStringFromException(e),
MediaType.APPLICATION_JSON);
getResponse().setStatus(Status.SUCCESS_OK);
LOG.error("Error in posting " + entity, e);
}
}
}