org.trafodion.rest.zookeeper.ZkQuorumPeer.java Source code

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Here is the source code for org.trafodion.rest.zookeeper.ZkQuorumPeer.java

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/**
 *(C) Copyright 2015 Hewlett-Packard Development Company, L.P.
 *
 * 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 org.trafodion.rest.zookeeper;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.Properties;
import java.util.Map.Entry;

import org.apache.hadoop.conf.Configuration;
import org.trafodion.rest.util.RestConfiguration;
import org.trafodion.rest.util.Strings;
import org.apache.hadoop.net.DNS;
import org.apache.hadoop.util.StringUtils;
import org.apache.zookeeper.server.ServerConfig;
import org.apache.zookeeper.server.ZooKeeperServerMain;
import org.apache.zookeeper.server.quorum.QuorumPeerConfig;
import org.apache.zookeeper.server.quorum.QuorumPeerMain;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * DCS's version of ZooKeeper's QuorumPeer. When DCS is set to manage
 * ZooKeeper, this class is used to start up QuorumPeer instances. By doing
 * things in here rather than directly calling to ZooKeeper, we have more
 * control over the process. This class uses {@link ZKConfig} to parse the
 * zoo.cfg and inject variables from DCS's site.xml configuration in.
 */
public class ZkQuorumPeer {
    /**
     * Parse ZooKeeper configuration from DCS XML config and run a QuorumPeer.
     * @param args String[] of command line arguments. Not used.
     */
    private static final Log LOG = LogFactory.getLog(ZkQuorumPeer.class.getName());

    public ZkQuorumPeer() {
        Configuration conf = RestConfiguration.create();
        try {
            Properties zkProperties = ZKConfig.makeZKProps(conf);
            writeMyID(zkProperties);
            QuorumPeerConfig zkConfig = new QuorumPeerConfig();
            zkConfig.parseProperties(zkProperties);
            System.out.println("running Zookeeper");
            runZKServer(zkConfig);
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(-1);
        }
    }

    public static void main(String[] args) {
        ZkQuorumPeer qp = new ZkQuorumPeer();
    }

    private static void runZKServer(QuorumPeerConfig zkConfig) throws UnknownHostException, IOException {
        if (zkConfig.isDistributed()) {
            QuorumPeerMain qp = new QuorumPeerMain();
            qp.runFromConfig(zkConfig);
        } else {
            ZooKeeperServerMain zk = new ZooKeeperServerMain();
            ServerConfig serverConfig = new ServerConfig();
            serverConfig.readFrom(zkConfig);
            zk.runFromConfig(serverConfig);
        }
    }

    private static boolean addressIsLocalHost(String address) {
        return address.equals("localhost") || address.equals("127.0.0.1");
    }

    static void writeMyID(Properties properties) throws IOException {
        long myId = -1;

        Configuration conf = RestConfiguration.create();
        String myAddress = Strings
                .domainNamePointerToHostName(DNS.getDefaultHost(conf.get("rest.zookeeper.dns.interface", "default"),
                        conf.get("rest.zookeeper.dns.nameserver", "default")));

        List<String> ips = new ArrayList<String>();

        // Add what could be the best (configured) match
        ips.add(myAddress.contains(".") ? myAddress : StringUtils.simpleHostname(myAddress));

        // For all nics get all hostnames and IPs
        Enumeration<?> nics = NetworkInterface.getNetworkInterfaces();
        while (nics.hasMoreElements()) {
            Enumeration<?> rawAdrs = ((NetworkInterface) nics.nextElement()).getInetAddresses();
            while (rawAdrs.hasMoreElements()) {
                InetAddress inet = (InetAddress) rawAdrs.nextElement();
                ips.add(StringUtils.simpleHostname(inet.getHostName()));
                ips.add(inet.getHostAddress());
            }
        }

        for (Entry<Object, Object> entry : properties.entrySet()) {
            String key = entry.getKey().toString().trim();
            String value = entry.getValue().toString().trim();
            if (key.startsWith("server.")) {
                int dot = key.indexOf('.');
                long id = Long.parseLong(key.substring(dot + 1));
                String[] parts = value.split(":");
                String address = parts[0];
                if (addressIsLocalHost(address) || ips.contains(address)) {
                    myId = id;
                    break;
                }
            }
        }

        // Set the max session timeout from the provided client-side timeout
        properties.setProperty("maxSessionTimeout", conf.get("zookeeper.session.timeout", "180000"));

        if (myId == -1) {
            throw new IOException(
                    "Could not find my address: " + myAddress + " in list of ZooKeeper quorum servers");
        }

        String dataDirStr = properties.get("dataDir").toString().trim();
        File dataDir = new File(dataDirStr);
        if (!dataDir.isDirectory()) {
            if (!dataDir.mkdirs()) {
                throw new IOException("Unable to create data dir " + dataDir);
            }
        }

        File myIdFile = new File(dataDir, "myid");
        PrintWriter w = new PrintWriter(myIdFile);
        w.println(myId);
        w.close();
    }
}