src/agent/subagents/bind9/src/main/java/com/github/tomaskir/netxms/subagents/bind9/collection/Collector.java

   1 package com.github.tomaskir.netxms.subagents.bind9.collection;
   2
   3 import com.github.tomaskir.netxms.subagents.bind9.Parameters;
   4 import com.github.tomaskir.netxms.subagents.bind9.exceptions.StatsFileRemovalException;
   5 import lombok.Builder;
   6 import org.netxms.agent.SubAgent;
   7
   8 import java.io.IOException;
   9 import java.nio.charset.StandardCharsets;
  10 import java.nio.file.Files;
  11 import java.nio.file.NoSuchFileException;
  12 import java.nio.file.Path;
  13 import java.util.List;
  14 import java.util.concurrent.locks.ReadWriteLock;
  15
  16 /**
  17  * @author Tomas Kirnak
  18  * @since 2.1-M1
  19  */
  20 public final class Collector implements Runnable {
  21
  22     private final long collectionInterval;
  23     private final Path statsFile;
  24     private final Parameters supportedParameters;
  25     private final CollectionResult result;
  26     private final ReadWriteLock dataCollectionLock;
  27
  28     private long lastCollection = 0;
  29     private boolean threadRunning = true;
  30
  31     // constructor
  32     @Builder
  33     public Collector(long collectionInterval, Path statsFile, Parameters supportedParameters,
  34                      CollectionResult result, ReadWriteLock dataCollectionLock) {
  35         this.collectionInterval = collectionInterval;
  36         this.statsFile = statsFile;
  37         this.supportedParameters = supportedParameters;
  38         this.result = result;
  39         this.dataCollectionLock = dataCollectionLock;
  40     }
  41
  42     public void terminate() {
  43         threadRunning = false;
  44     }
  45
  46     @Override
  47     public void run() {
  48         long now;
  49         Process rndc;
  50         List<String> lines;
  51
  52         while (threadRunning) {
  53             now = System.currentTimeMillis() / 1000;
  54
  55             if (now > lastCollection + collectionInterval) {
  56                 // remove existing statistics file
  57                 try {
  58                     statsFileCleanup();
  59                 } catch (StatsFileRemovalException e) {
  60                     SubAgent.writeLog(SubAgent.LogLevel.WARNING,
  61                             "Failed to delete bind9 statistics file, error: '" + e.getCause().getMessage() + "'");
  62
  63                     result.setCollectionError(true);
  64                     updateLastCollectionTime();
  65                     continue;
  66                 }
  67
  68                 // run "rndc stats" to generate new statistics file
  69                 try {
  70                     rndc = Runtime.getRuntime().exec("rndc stats");
  71                 } catch (IOException e) {
  72                     SubAgent.writeLog(SubAgent.LogLevel.ERROR,
  73                             "Failed to run 'rndc stats', error: '" + e.getMessage() + "'");
  74
  75                     result.setCollectionError(true);
  76                     updateLastCollectionTime();
  77                     continue;
  78                 }
  79
  80                 // wait for "rndc stats" to finish
  81                 try {
  82                     rndc.waitFor();
  83                 } catch (InterruptedException ignored) {
  84                     rndc.destroy();
  85                     continue;
  86                 }
  87
  88                 // check for errors
  89                 if (rndc.exitValue() != 0) {
  90                     SubAgent.writeLog(SubAgent.LogLevel.ERROR,
  91                             "'rndc stats' exited with a non-0 exit code value");
  92
  93                     result.setCollectionError(true);
  94                     updateLastCollectionTime();
  95                     continue;
  96                 }
  97
  98                 // load stats from the stats file
  99                 try {
 100                     lines = Files.readAllLines(statsFile, StandardCharsets.UTF_8);
 101                 } catch (IOException e) {
 102                     SubAgent.writeLog(SubAgent.LogLevel.WARNING,
 103                             "Unable to read bind9 statistics file, error: '" + e.getMessage() + "'");
 104
 105                     result.setCollectionError(true);
 106                     updateLastCollectionTime();
 107                     continue;
 108                 }
 109
 110                 // lock data collection lock for writing
 111                 dataCollectionLock.writeLock().lock();
 112
 113                 // remove previous values in result
 114                 result.getResult().clear();
 115
 116                 // for every parameter supported by this plugin
 117                 for (String[] entry : supportedParameters.getList()) {
 118                     // search all lines
 119                     for (String line : lines) {
 120                         int index = line.indexOf(entry[2]);
 121
 122                         // if attribute found
 123                         if (index != -1) {
 124                             // get value of the attribute
 125                             String value = line.substring(0, index).trim();
 126
 127                             // insert into the result map
 128                             result.getResult().put(entry[0], value);
 129
 130                             break;
 131                         }
 132                     }
 133                 }
 134
 135                 result.setCollectionError(false);
 136                 updateLastCollectionTime();
 137
 138                 // unlock data collection lock
 139                 dataCollectionLock.writeLock().unlock();
 140             }
 141
 142             try {
 143                 Thread.sleep(100);
 144             } catch (InterruptedException ignored) {
 145             }
 146         }
 147     }
 148
 149     private void statsFileCleanup() throws StatsFileRemovalException {
 150         try {
 151             Files.delete(statsFile);
 152         } catch (NoSuchFileException ignored) {
 153             // if the file doesn't exist, we do nothing
 154         } catch (IOException e) {
 155             throw new StatsFileRemovalException(e);
 156         }
 157     }
 158
 159     private void updateLastCollectionTime() {
 160         lastCollection = System.currentTimeMillis() / 1000;
 161     }
 162
 163 }