Examples with XRow org.opennms.netmgt.rrd.model.XRow used on opensource projects

Example 1 with XRow

use of org.opennms.netmgt.rrd.model.XRow in project opennms by OpenNMS.

the class RrdtoolXportFetchStrategy method fetchMeasurements.

/**
     * {@inheritDoc}
     */
@Override
protected FetchResults fetchMeasurements(long start, long end, long step, int maxrows, Map<Source, String> rrdsBySource, Map<String, Object> constants) throws RrdException {
    String rrdBinary = System.getProperty("rrd.binary");
    if (rrdBinary == null) {
        throw new RrdException("No RRD binary is set.");
    }
    final long startInSeconds = (long) Math.floor(start / 1000);
    final long endInSeconds = (long) Math.floor(end / 1000);
    long stepInSeconds = (long) Math.floor(step / 1000);
    // The step must be strictly positive
    if (stepInSeconds <= 0) {
        stepInSeconds = 1;
    }
    final CommandLine cmdLine = new CommandLine(rrdBinary);
    cmdLine.addArgument("xport");
    cmdLine.addArgument("--step");
    cmdLine.addArgument("" + stepInSeconds);
    cmdLine.addArgument("--start");
    cmdLine.addArgument("" + startInSeconds);
    cmdLine.addArgument("--end");
    cmdLine.addArgument("" + endInSeconds);
    if (maxrows > 0) {
        cmdLine.addArgument("--maxrows");
        cmdLine.addArgument("" + maxrows);
    }
    // Use labels without spaces when executing the xport command
    // These are mapped back to the requested labels in the response
    final Map<String, String> labelMap = Maps.newHashMap();
    int k = 0;
    for (final Map.Entry<Source, String> entry : rrdsBySource.entrySet()) {
        final Source source = entry.getKey();
        final String rrdFile = entry.getValue();
        final String tempLabel = Integer.toString(++k);
        labelMap.put(tempLabel, source.getLabel());
        cmdLine.addArgument(String.format("DEF:%s=%s:%s:%s", tempLabel, Utils.escapeColons(rrdFile), Utils.escapeColons(source.getEffectiveDataSource()), source.getAggregation()));
        cmdLine.addArgument(String.format("XPORT:%s:%s", tempLabel, tempLabel));
    }
    // Use commons-exec to execute rrdtool
    final DefaultExecutor executor = new DefaultExecutor();
    // Capture stdout/stderr
    final ByteArrayOutputStream stdout = new ByteArrayOutputStream();
    final ByteArrayOutputStream stderr = new ByteArrayOutputStream();
    executor.setStreamHandler(new PumpStreamHandler(stdout, stderr, null));
    // Fail if we get a non-zero exit code
    executor.setExitValue(0);
    // Fail if the process takes too long
    final ExecuteWatchdog watchdog = new ExecuteWatchdog(XPORT_TIMEOUT_MS);
    executor.setWatchdog(watchdog);
    // Export
    RrdXport rrdXport;
    try {
        LOG.debug("Executing: {}", cmdLine);
        executor.execute(cmdLine);
        final XMLReader xmlReader = XMLReaderFactory.createXMLReader();
        xmlReader.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
        final SAXSource source = new SAXSource(xmlReader, new InputSource(new StringReader(stdout.toString())));
        final JAXBContext jc = JAXBContext.newInstance(RrdXport.class);
        final Unmarshaller u = jc.createUnmarshaller();
        rrdXport = (RrdXport) u.unmarshal(source);
    } catch (IOException e) {
        throw new RrdException("An error occured while executing '" + StringUtils.join(cmdLine.toStrings(), " ") + "' with stderr: " + stderr.toString(), e);
    } catch (SAXException | JAXBException e) {
        throw new RrdException("The output generated by 'rrdtool xport' could not be parsed.", e);
    }
    final int numRows = rrdXport.getRows().size();
    final int numColumns = rrdXport.getMeta().getLegends().size();
    final long xportStartInMs = rrdXport.getMeta().getStart() * 1000;
    final long xportStepInMs = rrdXport.getMeta().getStep() * 1000;
    final long[] timestamps = new long[numRows];
    final double[][] values = new double[numColumns][numRows];
    // Convert rows to columns
    int i = 0;
    for (final XRow row : rrdXport.getRows()) {
        // Derive the timestamp from the start and step since newer versions
        // of rrdtool no longer include it as part of the rows
        timestamps[i] = xportStartInMs + xportStepInMs * i;
        for (int j = 0; j < numColumns; j++) {
            if (row.getValues() == null) {
                // NMS-7710: Avoid NPEs, in certain cases the list of values may be null
                throw new RrdException("The output generated by 'rrdtool xport' was not recognized. Try upgrading your rrdtool binaries.");
            }
            values[j][i] = row.getValues().get(j);
        }
        i++;
    }
    // Map the columns by label
    // The legend entries are in the same order as the column values
    final Map<String, double[]> columns = Maps.newHashMapWithExpectedSize(numColumns);
    i = 0;
    for (String label : rrdXport.getMeta().getLegends()) {
        columns.put(labelMap.get(label), values[i++]);
    }
    return new FetchResults(timestamps, columns, xportStepInMs, constants);
}