/**
* 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.api.handlers;
import org.apache.ambari.server.api.query.Query;
import org.apache.ambari.server.api.resources.*;
import org.apache.ambari.server.api.services.*;
import org.apache.ambari.server.api.services.persistence.PersistenceManager;
import org.apache.ambari.server.api.services.persistence.PersistenceManagerImpl;
import org.apache.ambari.server.api.util.TreeNode;
import org.apache.ambari.server.controller.spi.ClusterController;
import org.apache.ambari.server.controller.spi.Predicate;
import org.apache.ambari.server.controller.spi.RequestStatus;
import org.apache.ambari.server.controller.spi.Resource;
import org.apache.ambari.server.controller.utilities.ClusterControllerHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Set;
/**
* Base handler for operations that persist state to the back-end.
*/
public abstract class BaseManagementHandler implements RequestHandler {
/**
* Logger instance.
*/
protected final static Logger LOG =
LoggerFactory.getLogger(BaseManagementHandler.class);
public static final String RESOURCES_NODE_NAME = "resources";
/**
* PersistenceManager implementation.
*/
PersistenceManager m_pm = new PersistenceManagerImpl(getClusterController());
/**
* Constructor.
*/
protected BaseManagementHandler() {
}
@Override
public Result handleRequest(Request request) {
Query query = request.getResource().getQuery();
Predicate queryPredicate = request.getQueryPredicate();
query.setRenderer(request.getRenderer());
if (queryPredicate != null) {
query.setUserPredicate(queryPredicate);
}
return persist(request.getResource(), request.getBody());
}
/**
* Create a result from a request status.
*
* @param requestStatus the request status to build the result from.
*
* @return a Result instance for the provided request status
*/
protected Result createResult(RequestStatus requestStatus) {
boolean isSynchronous = requestStatus.getStatus() == RequestStatus.Status.Complete;
Result result = new ResultImpl(isSynchronous);
TreeNode<Resource> tree = result.getResultTree();
if (! isSynchronous) {
tree.addChild(requestStatus.getRequestResource(), "request");
}
Set<Resource> setResources = requestStatus.getAssociatedResources();
if (! setResources.isEmpty()) {
TreeNode<Resource> resourcesNode = tree.addChild(null, RESOURCES_NODE_NAME);
resourcesNode.setProperty("isCollection", "true");
int count = 1;
for (Resource resource : setResources) {
//todo: provide a more meaningful node name
resourcesNode.addChild(resource, resource.getType() + ":" + count++);
}
}
return result;
}
//todo: inject ClusterController, PersistenceManager
/**
* Get the cluster controller instance.
*
* @return cluster controller
*/
protected ClusterController getClusterController() {
return ClusterControllerHelper.getClusterController();
}
/**
* Get the persistence manager instance.
*
* @return persistence manager
*/
protected PersistenceManager getPersistenceManager() {
return m_pm;
}
/**
* Persist the operation to the back end.
*
* @param resource associated resource
* @param body associated request body
*
* @return the result of the persist operation
*/
protected abstract Result persist(ResourceInstance resource, RequestBody body);
}