com.netflix.exhibitor.core.automanage.ClusterStatusTask.java Source code

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Here is the source code for com.netflix.exhibitor.core.automanage.ClusterStatusTask.java

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/*
 * Copyright 2012 Netflix, Inc.
 *
 *    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.netflix.exhibitor.core.automanage;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.netflix.exhibitor.core.Exhibitor;
import com.netflix.exhibitor.core.entities.ServerStatus;
import com.netflix.exhibitor.core.state.InstanceStateTypes;
import com.netflix.exhibitor.core.state.ServerList;
import com.netflix.exhibitor.core.state.ServerSpec;
import jsr166y.RecursiveTask;
import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.map.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.List;

public class ClusterStatusTask extends RecursiveTask<List<ServerStatus>> {
    private final Logger log = LoggerFactory.getLogger(getClass());
    private final Exhibitor exhibitor;
    private final List<ServerSpec> specs;
    private final ServerSpec us;

    public ClusterStatusTask(Exhibitor exhibitor, List<ServerSpec> specs) {
        this.exhibitor = exhibitor;
        this.specs = ImmutableList.copyOf(specs);
        us = Iterables.find(specs, ServerList.isUs(exhibitor.getThisJVMHostname()), null);
    }

    @Override
    protected List<ServerStatus> compute() {
        List<ServerStatus> statuses = Lists.newArrayList();

        int size = specs.size();
        switch (size) {
        case 0: {
            break; // nothing to do
        }

        case 1: {
            statuses.add(getStatus(specs.get(0)));
            break;
        }

        default: {
            List<ClusterStatusTask> tasks = Lists.newArrayList();
            for (List<ServerSpec> subList : Lists.partition(specs, size / 2)) {
                ClusterStatusTask task = new ClusterStatusTask(exhibitor, subList);
                task.fork();
                tasks.add(task);
            }

            for (ClusterStatusTask task : tasks) {
                statuses.addAll(task.join());
            }
            break;
        }
        }
        return statuses;
    }

    private ServerStatus getStatus(ServerSpec spec) {
        if (spec.equals(us)) {
            InstanceStateTypes state = exhibitor.getMonitorRunningInstance().getCurrentInstanceState();
            return new ServerStatus(spec.getHostname(), state.getCode(), state.getDescription(),
                    exhibitor.getMonitorRunningInstance().isCurrentlyLeader());
        }

        try {
            RemoteInstanceRequest request = new RemoteInstanceRequest(exhibitor, spec.getHostname());
            RemoteInstanceRequest.Result result = request.makeRequest(exhibitor.getRemoteInstanceRequestClient(),
                    "getStatus");

            ObjectMapper mapper = new ObjectMapper();
            JsonNode value = mapper.readTree(mapper.getJsonFactory().createJsonParser(result.remoteResponse));
            if (value.size() == 0) {
                return new ServerStatus(spec.getHostname(), InstanceStateTypes.DOWN.getCode(),
                        InstanceStateTypes.DOWN.getDescription(), false);
            }

            int code = value.get("state").getValueAsInt();
            String description = value.get("description").getTextValue();
            return new ServerStatus(spec.getHostname(), code, description, value.get("isLeader").getBooleanValue());
        } catch (IOException e) {
            log.error("Getting remote server status", e);
            throw new RuntimeException(e);
        }
    }
}