package org.apache.helix.webapp.resources;
/*
* 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.
*/
import java.util.Map;
import org.apache.helix.HelixAdmin;
import org.apache.helix.ZNRecord;
import org.apache.helix.manager.zk.ZKHelixAdmin;
import org.apache.helix.manager.zk.ZkClient;
import org.apache.helix.model.ClusterConstraints.ConstraintType;
import org.apache.helix.tools.ClusterSetup;
import org.apache.helix.webapp.RestAdminApplication;
import org.apache.log4j.Logger;
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;
public class ConstraintResource extends Resource {
private final static Logger LOG = Logger.getLogger(ConstraintResource.class);
public ConstraintResource(Context context, Request request, Response response)
{
super(context, request, response);
getVariants().add(new Variant(MediaType.TEXT_PLAIN));
getVariants().add(new Variant(MediaType.APPLICATION_JSON));
setModifiable(true);
}
// TODO move to a util function
String getValue(String key)
{
return (String) getRequest().getAttributes().get(key);
}
@Override
public Representation represent(Variant variant)
{
StringRepresentation representation = null;
String clusterName = getValue("clusterName");
String constraintTypeStr = getValue("constraintType").toUpperCase();
String constraintId = getValue("constraintId");
try {
ConstraintType constraintType = ConstraintType.valueOf(constraintTypeStr);
ZkClient zkClient =
(ZkClient) getContext().getAttributes().get(RestAdminApplication.ZKCLIENT);
// ClusterSetup setupTool = new ClusterSetup(zkClient);
HelixAdmin admin = new ZKHelixAdmin(zkClient); // setupTool.getClusterManagementTool();
ZNRecord record = admin.getConstraints(clusterName, constraintType).getRecord();
if (constraintId == null) {
// get all message constraints
representation = new StringRepresentation(ClusterRepresentationUtil.ZNRecordToJson(record),
MediaType.APPLICATION_JSON);
} else {
// get a specific constraint
Map<String, String> constraint = record.getMapField(constraintId);
if (constraint == null) {
representation = new StringRepresentation("No constraint of type: "
+ constraintType + " associated with id: " + constraintId, MediaType.APPLICATION_JSON);
} else {
ZNRecord subRecord = new ZNRecord(record.getId());
subRecord.setMapField(constraintId, constraint);
representation = new StringRepresentation(ClusterRepresentationUtil.ZNRecordToJson(subRecord),
MediaType.APPLICATION_JSON);
}
}
}
catch (IllegalArgumentException e) {
representation = new StringRepresentation("constraint-type: " + constraintTypeStr + " not recognized.",
MediaType.APPLICATION_JSON);
}
catch (Exception e)
{
String error = ClusterRepresentationUtil.getErrorAsJsonStringFromException(e);
representation = new StringRepresentation(error, MediaType.APPLICATION_JSON);
LOG.error("", e);
}
return representation;
}
@Override
public void acceptRepresentation(Representation entity)
{
String clusterName = getValue("clusterName");
String constraintTypeStr = getValue("constraintType").toUpperCase();
String constraintId = getValue("constraintId");
try {
ZkClient zkClient =
(ZkClient) getContext().getAttributes().get(RestAdminApplication.ZKCLIENT);
ClusterSetup setupTool = new ClusterSetup(zkClient);
JsonParameters jsonParameters = new JsonParameters(entity);
String constraintAttrStr = jsonParameters.getParameter(JsonParameters.CONSTRAINT_ATTRIBUTES);
setupTool.setConstraint(clusterName, constraintTypeStr, constraintId, constraintAttrStr);
}
catch (Exception e)
{
LOG.error("Error in posting " + entity, e);
getResponse().setEntity(ClusterRepresentationUtil.getErrorAsJsonStringFromException(e),
MediaType.APPLICATION_JSON);
getResponse().setStatus(Status.SUCCESS_OK);
}
}
@Override
public void removeRepresentations()
{
String clusterName = getValue("clusterName");
String constraintTypeStr = getValue("constraintType").toUpperCase();
String constraintId = getValue("constraintId");
try {
ZkClient zkClient =
(ZkClient) getContext().getAttributes().get(RestAdminApplication.ZKCLIENT);
ClusterSetup setupTool = new ClusterSetup(zkClient);
setupTool.removeConstraint(clusterName, constraintTypeStr, constraintId);
}
catch (Exception e)
{
LOG.error("Error in deleting ", e);
getResponse().setEntity(ClusterRepresentationUtil.getErrorAsJsonStringFromException(e),
MediaType.APPLICATION_JSON);
getResponse().setStatus(Status.SUCCESS_OK);
}
}
}