org.apache.whirr.service.zookeeper.ZooKeeperService.java Source code

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Here is the source code for org.apache.whirr.service.zookeeper.ZooKeeperService.java

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/**
 * 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.whirr.service.zookeeper;

import static com.google.common.base.Preconditions.checkNotNull;
import static org.jclouds.compute.options.TemplateOptions.Builder.runScript;

import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.collect.Collections2;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.common.collect.Sets;

import java.io.IOException;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.whirr.service.ClusterSpec;
import org.apache.whirr.service.ComputeServiceBuilder;
import org.apache.whirr.service.RunUrlBuilder;
import org.apache.whirr.service.Service;
import org.apache.whirr.service.ServiceSpec;
import org.apache.whirr.service.Cluster.Instance;
import org.apache.whirr.service.ClusterSpec.InstanceTemplate;
import org.jclouds.compute.ComputeService;
import org.jclouds.compute.RunNodesException;
import org.jclouds.compute.RunScriptOnNodesException;
import org.jclouds.compute.domain.NodeMetadata;
import org.jclouds.compute.domain.OsFamily;
import org.jclouds.compute.domain.Template;

public class ZooKeeperService extends Service {

    public static final String ZOOKEEPER_ROLE = "zk";
    private static final int CLIENT_PORT = 2181;

    public ZooKeeperService(ServiceSpec serviceSpec) {
        super(serviceSpec);
    }

    @Override
    public ZooKeeperCluster launchCluster(ClusterSpec clusterSpec) throws IOException {

        ComputeService computeService = ComputeServiceBuilder.build(serviceSpec);

        byte[] bootScript = RunUrlBuilder.runUrls("sun/java/install", "apache/zookeeper/install");
        Template template = computeService.templateBuilder().osFamily(OsFamily.UBUNTU)
                .options(runScript(bootScript).installPrivateKey(serviceSpec.readPrivateKey())
                        .authorizePublicKey(serviceSpec.readPublicKey()).inboundPorts(22, CLIENT_PORT))
                .build();

        InstanceTemplate instanceTemplate = clusterSpec.getInstanceTemplate(ZOOKEEPER_ROLE);
        checkNotNull(instanceTemplate);
        int ensembleSize = instanceTemplate.getNumberOfInstances();
        Set<? extends NodeMetadata> nodeMap;
        try {
            nodeMap = computeService.runNodesWithTag(serviceSpec.getClusterName(), ensembleSize, template);
        } catch (RunNodesException e) {
            // TODO: can we do better here - proceed if ensemble is big enough?
            throw new IOException(e);
        }
        List<NodeMetadata> nodes = Lists.newArrayList(nodeMap);

        // Pass list of all servers in ensemble to configure script.
        // Position is significant: i-th server has id i.
        String servers = Joiner.on(' ').join(getPrivateIps(nodes));
        byte[] configureScript = RunUrlBuilder.runUrls("apache/zookeeper/post-configure " + servers);
        try {
            computeService.runScriptOnNodesWithTag(serviceSpec.getClusterName(), configureScript);
        } catch (RunScriptOnNodesException e) {
            // TODO: retry
            throw new IOException(e);
        }

        String hosts = Joiner.on(',').join(getHosts(nodes));
        return new ZooKeeperCluster(getInstances(nodes), hosts);
    }

    private List<String> getPrivateIps(List<NodeMetadata> nodes) {
        return Lists.transform(Lists.newArrayList(nodes), new Function<NodeMetadata, String>() {
            @Override
            public String apply(NodeMetadata node) {
                return Iterables.get(node.getPrivateAddresses(), 0).getHostAddress();
            }
        });
    }

    private Set<Instance> getInstances(List<NodeMetadata> nodes) {
        return Sets
                .newHashSet(Collections2.transform(Sets.newHashSet(nodes), new Function<NodeMetadata, Instance>() {
                    @Override
                    public Instance apply(NodeMetadata node) {
                        return new Instance(Collections.singleton(ZOOKEEPER_ROLE),
                                Iterables.get(node.getPublicAddresses(), 0),
                                Iterables.get(node.getPrivateAddresses(), 0));
                    }
                }));
    }

    private List<String> getHosts(List<NodeMetadata> nodes) {
        return Lists.transform(Lists.newArrayList(nodes), new Function<NodeMetadata, String>() {
            @Override
            public String apply(NodeMetadata node) {
                String publicIp = Iterables.get(node.getPublicAddresses(), 0).getHostName();
                return String.format("%s:%d", publicIp, CLIENT_PORT);
            }
        });
    }

}