/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.rest.action.admin.cluster;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.admin.cluster.node.tasks.list.ListTasksRequest;
import org.elasticsearch.action.admin.cluster.node.tasks.list.ListTasksResponse;
import org.elasticsearch.client.node.NodeClient;
import org.elasticsearch.cluster.node.DiscoveryNodes;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.rest.BaseRestHandler;
import org.elasticsearch.rest.BytesRestResponse;
import org.elasticsearch.rest.RestChannel;
import org.elasticsearch.rest.RestController;
import org.elasticsearch.rest.RestRequest;
import org.elasticsearch.rest.RestResponse;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.rest.action.RestBuilderListener;
import org.elasticsearch.rest.action.RestToXContentListener;
import org.elasticsearch.tasks.TaskId;
import java.io.IOException;
import java.util.function.Supplier;
import static org.elasticsearch.rest.RestRequest.Method.GET;
public class RestListTasksAction extends BaseRestHandler {
private final Supplier<DiscoveryNodes> nodesInCluster;
public RestListTasksAction(Settings settings, RestController controller, Supplier<DiscoveryNodes> nodesInCluster) {
super(settings);
this.nodesInCluster = nodesInCluster;
controller.registerHandler(GET, "/_tasks", this);
}
@Override
public RestChannelConsumer prepareRequest(final RestRequest request, final NodeClient client) throws IOException {
final ListTasksRequest listTasksRequest = generateListTasksRequest(request);
final String groupBy = request.param("group_by", "nodes");
return channel -> client.admin().cluster().listTasks(listTasksRequest,
listTasksResponseListener(nodesInCluster, groupBy, channel));
}
public static ListTasksRequest generateListTasksRequest(RestRequest request) {
boolean detailed = request.paramAsBoolean("detailed", false);
String[] nodes = Strings.splitStringByCommaToArray(request.param("nodes"));
String[] actions = Strings.splitStringByCommaToArray(request.param("actions"));
TaskId parentTaskId = new TaskId(request.param("parent_task_id"));
boolean waitForCompletion = request.paramAsBoolean("wait_for_completion", false);
TimeValue timeout = request.paramAsTime("timeout", null);
ListTasksRequest listTasksRequest = new ListTasksRequest();
listTasksRequest.setNodes(nodes);
listTasksRequest.setDetailed(detailed);
listTasksRequest.setActions(actions);
listTasksRequest.setParentTaskId(parentTaskId);
listTasksRequest.setWaitForCompletion(waitForCompletion);
listTasksRequest.setTimeout(timeout);
return listTasksRequest;
}
/**
* Standard listener for extensions of {@link ListTasksResponse} that supports {@code group_by=nodes}.
*/
public static <T extends ListTasksResponse> ActionListener<T> listTasksResponseListener(
Supplier<DiscoveryNodes> nodesInCluster,
String groupBy,
final RestChannel channel) {
if ("nodes".equals(groupBy)) {
return new RestBuilderListener<T>(channel) {
@Override
public RestResponse buildResponse(T response, XContentBuilder builder) throws Exception {
builder.startObject();
response.toXContentGroupedByNode(builder, channel.request(), nodesInCluster.get());
builder.endObject();
return new BytesRestResponse(RestStatus.OK, builder);
}
};
} else if ("parents".equals(groupBy)) {
return new RestToXContentListener<>(channel);
} else {
throw new IllegalArgumentException("[group_by] must be one of [nodes] or [parents] but was [" + groupBy + "]");
}
}
@Override
public boolean canTripCircuitBreaker() {
return false;
}
}