TcpMonitor.java

/*******************************************************************************
 * This file is part of OpenNMS(R).
 *
 * Copyright (C) 2006-2011 The OpenNMS Group, Inc.
 * OpenNMS(R) is Copyright (C) 1999-2011 The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation, either version 3 of the License,
 * or (at your option) any later version.
 *
 * OpenNMS(R) is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OpenNMS(R).  If not, see:
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 *
 * For more information contact:
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package org.opennms.netmgt.poller.monitors;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.InterruptedIOException;
import java.net.ConnectException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NoRouteToHostException;
import java.net.Socket;
import java.util.Map;

import org.apache.log4j.Level;
import org.opennms.core.utils.InetAddressUtils;
import org.opennms.core.utils.ParameterMap;
import org.opennms.core.utils.TimeoutTracker;
import org.opennms.netmgt.model.PollStatus;
import org.opennms.netmgt.poller.Distributable;
import org.opennms.netmgt.poller.MonitoredService;
import org.opennms.netmgt.poller.NetworkInterface;
import org.opennms.netmgt.poller.NetworkInterfaceNotSupportedException;

/**
 * This class is designed to be used by the service poller framework to test the
 * availability of a generic TCP service on remote interfaces. The class
 * implements the ServiceMonitor interface that allows it to be used along with
 * other plug-ins by the service poller framework.
 *
 * @author Weave
 * @author <A HREF="mailto:tarus@opennms.org">Tarus Balog </A>
 * @author <A HREF="mike@opennms.org">Mike </A>
 * @author <A HREF="http://www.opennms.org/">OpenNMS </A>
 */

@Distributable
final public class TcpMonitor extends AbstractServiceMonitor {

    /**
     * Default port.
     */
    private static final int DEFAULT_PORT = -1;

    /**
     * Default retries.
     */
    private static final int DEFAULT_RETRY = 0;

    /**
     * Default timeout. Specifies how long (in milliseconds) to block waiting
     * for data from the monitored interface.
     */
    private static final int DEFAULT_TIMEOUT = 3000; // 3 second timeout on
                                                        // read()

    public static final String PARAMETER_BANNER = "banner";
    public static final String PARAMETER_PORT = "port";

    /**
     * {@inheritDoc}
     *
     * Poll the specified address for service availability.
     *
     * During the poll an attempt is made to connect on the specified port. If
     * the connection request is successful, the banner line generated by the
     * interface is parsed and if the banner text indicates that we are talking
     * to Provided that the interface's response is valid we set the service
     * status to SERVICE_AVAILABLE and return.
     */
    public PollStatus poll(MonitoredService svc, Map<String, Object> parameters) {
        NetworkInterface<InetAddress> iface = svc.getNetInterface();

        //
        // Process parameters
        //

        //
        // Get interface address from NetworkInterface
        //
        if (iface.getType() != NetworkInterface.TYPE_INET)
            throw new NetworkInterfaceNotSupportedException("Unsupported interface type, only TYPE_INET currently supported");

        TimeoutTracker tracker = new TimeoutTracker(parameters, DEFAULT_RETRY, DEFAULT_TIMEOUT);

        // Port
        //
        int port = ParameterMap.getKeyedInteger(parameters, PARAMETER_PORT, DEFAULT_PORT);
        if (port == DEFAULT_PORT) {
            throw new RuntimeException("TcpMonitor: required parameter 'port' is not present in supplied properties.");
        }

        // BannerMatch
        //
        String strBannerMatch = ParameterMap.getKeyedString(parameters, PARAMETER_BANNER, null);

        // Get the address instance.
        //
        InetAddress ipv4Addr = (InetAddress) iface.getAddress();

        final String hostAddress = InetAddressUtils.str(ipv4Addr);
		if (log().isDebugEnabled())
            log().debug("poll: address = " + hostAddress + ", port = " + port + ", " + tracker);

        // Give it a whirl
        //
        PollStatus serviceStatus = PollStatus.unavailable();

        for (tracker.reset(); tracker.shouldRetry() && !serviceStatus.isAvailable(); tracker.nextAttempt()) {
            Socket socket = null;
            try {
                
                tracker.startAttempt();

                socket = new Socket();
                socket.connect(new InetSocketAddress(ipv4Addr, port), tracker.getConnectionTimeout());
                socket.setSoTimeout(tracker.getSoTimeout());
                log().debug("TcpMonitor: connected to host: " + ipv4Addr + " on port: " + port);

                // We're connected, so upgrade status to unresponsive
                serviceStatus = PollStatus.unresponsive();

                if (strBannerMatch == null || strBannerMatch.length() == 0 || strBannerMatch.equals("*")) {
                    serviceStatus = PollStatus.available(tracker.elapsedTimeInMillis());
                    break;
                }

                BufferedReader rdr = new BufferedReader(new InputStreamReader(socket.getInputStream()));

                //
                // Tokenize the Banner Line, and check the first
                // line for a valid return.
                //
                String response = rdr.readLine();
                double responseTime = tracker.elapsedTimeInMillis();

                if (response == null)
                    continue;
                if (log().isDebugEnabled()) {
                    log().debug("poll: banner = " + response);
                    log().debug("poll: responseTime= " + responseTime + "ms");
                }

                if (response.indexOf(strBannerMatch) > -1) {
                    serviceStatus = PollStatus.available(responseTime);
                } else
                    serviceStatus = PollStatus.unavailable("Banner: '"+response+"' does not contain match string '"+strBannerMatch+"'");
            } catch (NoRouteToHostException e) {
            	serviceStatus = logDown(Level.WARN, "No route to host exception for address " + hostAddress, e);
                break; // Break out of for(;;)
            } catch (InterruptedIOException e) {
            	serviceStatus = logDown(Level.DEBUG, "did not connect to host with " + tracker);
            } catch (ConnectException e) {
            	serviceStatus = logDown(Level.DEBUG, "Connection exception for address: " + ipv4Addr, e);
            } catch (IOException e) {
            	serviceStatus = logDown(Level.DEBUG, "IOException while polling address: " + ipv4Addr, e);
            } finally {
                try {
                    // Close the socket
                    if (socket != null)
                        socket.close();
                } catch (IOException e) {
                    e.fillInStackTrace();
                    if (log().isDebugEnabled())
                        log().debug("poll: Error closing socket.", e);
                }
            }
        }

        //
        // return the status of the service
        //
        return serviceStatus;
    }

}