storm.mesos.logviewer.LogViewerController.java Source code

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Here is the source code for storm.mesos.logviewer.LogViewerController.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 storm.mesos.logviewer;

import org.apache.storm.Config;
import com.google.common.base.Optional;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.IOException;
import java.lang.ProcessBuilder.Redirect;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Map;

public class LogViewerController {
    private static final Logger LOG = LoggerFactory.getLogger(LogViewerController.class);
    protected Process process;
    protected SocketUrlDetection urlDetector;
    protected Integer port;

    public LogViewerController(Map conf) {
        port = Optional.fromNullable((Number) conf.get(Config.LOGVIEWER_PORT)).or(8000).intValue();
        setUrlDetector(new SocketUrlDetection(port));
    }

    /**
     * Start up the logviewer, but before that is done a check is made to
     * see if an existing logviewer (or process) is on the same port and report
     * and error if so.
     */
    public void start() {
        try {
            if (!exists()) {
                launchLogViewer();
            } else {
                LOG.error("Failed to start logviewer because there is something on its port");
            }
        } catch (Exception e) {
            LOG.error("Failed to start logviewer", e);
        }
    }

    public void stop() {
        getProcess().destroy();
    }

    public boolean exists() {
        return getUrlDetector().isReachable();
    }

    public SocketUrlDetection getUrlDetector() {
        return urlDetector;
    }

    public void setUrlDetector(SocketUrlDetection urlDetector) {
        this.urlDetector = urlDetector;
    }

    protected Process getProcess() {
        return process;
    }

    protected void setProcess(Process process) {
        this.process = process;
    }

    protected void launchLogViewer() throws IOException {
        ProcessBuilder pb = createProcessBuilder();
        setProcess(pb.start());
    }

    /**
     * Create a process builder to launch the log viewer
     * @param logDirectory
     * @return
     */
    protected ProcessBuilder createProcessBuilder() {
        ProcessBuilder pb = new ProcessBuilder(Paths.get(System.getProperty("user.dir"), "/bin/storm").toString(),
                "logviewer", "-c", "storm.log.dir=" + System.getenv("MESOS_SANDBOX") + "/logs", "-c",
                Config.LOGVIEWER_PORT + "=" + port);

        // If anything goes wrong at startup we want to see it.
        Path logPath = Paths.get(System.getenv("MESOS_SANDBOX"), "/logs");
        if (!logPath.toFile().exists() && !logPath.toFile().mkdirs()) {
            throw new RuntimeException("Couldn't create log directory");
        }
        File log = Paths.get(System.getenv("MESOS_SANDBOX"), "/logs/logviewer-startup.log").toFile();
        pb.redirectErrorStream(true);
        pb.redirectOutput(Redirect.appendTo(log));
        return pb;
    }
}