/*******************************************************************************
* Copyright (c) 2007, 2014 Massimiliano Ziccardi
*
* 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 it.jnrpe.plugin;
import it.jnrpe.ICommandLine;
import it.jnrpe.Status;
import it.jnrpe.plugins.Metric;
import it.jnrpe.plugins.MetricGatheringException;
import it.jnrpe.plugins.PluginBase;
import it.jnrpe.plugins.annotations.Option;
import it.jnrpe.plugins.annotations.Plugin;
import it.jnrpe.plugins.annotations.PluginOptions;
import it.jnrpe.utils.BadThresholdException;
import it.jnrpe.utils.StreamManager;
import it.jnrpe.utils.thresholds.ThresholdsEvaluatorBuilder;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
/**
* This plugin checks the number of users currently logged in on the local
* system and generates a critical or an error status according to the passed-in
* thresholds.
*
* @author Frederico Campos
*
*/
@Plugin(name = "CHECK_USERS", description = "This plugin checks the number of users currently logged in on the\n"
+ "local system and generates an error if the number exceeds the thresholds specified.\n"
+ "EXAMPLES\n"
+ "The example will be based upon the following command definition (ini file)\n\n"
+
"check_user : CHECK_USER --warning $ARG1$ --critical $ARG2$\n\n"
+
"* Example 1 (Windows and Unix)\n"
+ "The following example will give a WARNING if the number of logged in users exceeds 10 and a CRITICAL message if the number of users exceeds 20\n\n"
+
"check_nrpe -H myjnrpeserver -c check_users -a '10:!20:'")
@PluginOptions({
@Option(shortName = "w", longName = "warning", description = "Set WARNING status if more than INTEGER users are logged in", required = false, hasArgs = true, argName = "warning", optionalArgs = false, option = "warning"),
@Option(shortName = "c", longName = "critical", description = "Set CRITICAL status if more than INTEGER users are logged in", required = false, hasArgs = true, argName = "critical", optionalArgs = false, option = "critical"),
@Option(shortName = "T", longName = "th", description = "Configure a threshold. Format : metric={metric},ok={range},warn={range},crit={range},unit={unit},prefix={SI prefix}", required = false, hasArgs = true, argName = "critical", optionalArgs = false, option = "th") })
public class CheckUsers extends PluginBase {
@Override
public void configureThresholdEvaluatorBuilder(final ThresholdsEvaluatorBuilder thrb, final ICommandLine cl) throws BadThresholdException {
if (cl.hasOption("th")) {
super.configureThresholdEvaluatorBuilder(thrb, cl);
} else {
thrb.withLegacyThreshold("users", null, cl.getOptionValue("warning"), cl.getOptionValue("critical"));
}
}
@Override
public Collection<Metric> gatherMetrics(ICommandLine cl) throws MetricGatheringException {
List<Metric> metricList = new ArrayList<Metric>();
String os = System.getProperty("os.name").toLowerCase();
try {
if (os.contains("linux")) {
metricList.add(new Metric("users", "", new BigDecimal(getLinuxLoggedInUsers()), null, null));
} else if (os.contains("windows")) {
metricList.add(new Metric("users", "", new BigDecimal(getWindowsLoggedInUsers()), null, null));
}
return metricList;
} catch (IOException e) {
String message = e.getMessage();
LOG.warn(getContext(), "CheckUser plugin execution error: " + message, e);
throw new MetricGatheringException("An error has occurred : " + message, Status.UNKNOWN, e);
}
}
/**
* Get list of logged in users for linux.
*
* @return The number of logged in users
* @throws IOException
* -
*/
private int getLinuxLoggedInUsers() throws IOException {
String command = "/usr/bin/users";
List<String> users = new ArrayList<String>();
ProcessBuilder builder = new ProcessBuilder();
Process proc = null;
proc = builder.command(command).start();
StreamManager sm = new StreamManager();
try {
InputStream stdin = sm.handle(proc.getInputStream());
Reader isr = sm.handle(new InputStreamReader(stdin, "UTF-8"));
BufferedReader br = (BufferedReader) sm.handle(new BufferedReader(isr));
String line = null;
while ((line = br.readLine()) != null) {
users.add(line);
}
return users.size();
} finally {
// Close all the streams/readers
sm.closeAll();
}
}
/**
* Get list of logged in users for windows by counting the number of
* explorer.exe processes.
*
* @return The number of logged in windows users
* @throws IOException
* -
*/
private int getWindowsLoggedInUsers() throws IOException {
String command = System.getenv("windir") + "\\system32\\" + "tasklist.exe";
int userCount = 0;
ProcessBuilder builder = new ProcessBuilder();
Process proc = null;
proc = builder.command(command).start();
StreamManager sm = new StreamManager();
try {
InputStream stdin = sm.handle(proc.getInputStream());
Reader isr = sm.handle(new InputStreamReader(stdin));
BufferedReader br = (BufferedReader) sm.handle(new BufferedReader(isr));
String line = null;
while ((line = br.readLine()) != null) {
if (line.contains("explorer.exe")) {
userCount++;
}
}
return userCount;
} finally {
sm.closeAll();
}
}
@Override
protected String getPluginName() {
return "CHECK_USERS";
}
}