com.blackberry.logdriver.LockedFsShell.java Source code

Introduction

Here is the source code for com.blackberry.logdriver.LockedFsShell.java

Source

/** Copyright (c) 2014 BlackBerry Limited
 *
 *  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.blackberry.logdriver;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FsShell;
import org.apache.hadoop.util.ToolRunner;
import org.apache.zookeeper.KeeperException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.blackberry.logdriver.fs.PathInfo;
import com.blackberry.logdriver.locks.LockUtil;

public class LockedFsShell {
    private static final Logger LOG = LoggerFactory.getLogger(LockedFsShell.class);

    public static void main(String[] args) {
        // The required args are zkConnectString, dcNumber, service, date, hour,
        // component and an arbitrary number of commands.
        if (args.length < 7) {
            printUsage();
            System.exit(1);
        }

        String zkConnectString = args[0];
        String dcNumber = args[1];
        String service = args[2];
        String date = args[3];
        String hour = args[4];
        String component = args[5];

        // Set the configuration correctly, so we can reach zookeeper
        Configuration conf = new Configuration();
        conf.set("zk.connect.string", zkConnectString);

        try {
            LockUtil lockUtil = new LockUtil(conf);

            PathInfo pathInfo = new PathInfo();
            pathInfo.setDcNumber(dcNumber);
            pathInfo.setService(service);
            pathInfo.setDate(date);
            pathInfo.setHour(hour);
            pathInfo.setComponent(component);

            String lockPath = lockUtil.getLockPath(pathInfo);

            // Get the write lock
            while (true) {
                try {
                    lockUtil.acquireWriteLock(lockPath);
                    break;
                } catch (KeeperException.ConnectionLossException e) {
                    LOG.warn("Lost connection to ZooKeeper.  Retrying.", e);
                }
            }

            // Run the commands
            int res = 0;

            for (int i = 6; i < args.length; i++) {
                String[] fsShellArgs = args[i].split("\\s+");
                LOG.info("Calling FsShell with args {}", args[i]);
                FsShell shell = new FsShell();
                try {
                    res = ToolRunner.run(shell, fsShellArgs);
                } finally {
                    shell.close();
                }

                if (res != 0) {
                    break;
                }
            }

            // Release the write lock
            while (true) {
                try {
                    lockUtil.releaseWriteLock(lockPath);
                    break;
                } catch (KeeperException.ConnectionLossException e) {
                    LOG.warn("Lost connection to ZooKeeper.  Retrying.", e);
                }
            }

            if (res != 0) {
                LOG.error("Bad return value ({}) from FsShell", res);
                System.exit(res);
            }

        } catch (Exception e) {
            e.printStackTrace();
            System.exit(1);
        }
    }

    private static void printUsage() {
        System.out.println(
                "Usage: " + LockedFsShell.class.getSimpleName() + " <zkConnectString> <dcNumber> <service> "
                        + "<yyyymmdd> <hh> <component> <command> [<command> ...]");
    }

}