OVMS3/OVMS.V3/components/ovms_webserver/dev/metrics.htm

<!--
  Test/Development/Documentation page; install as plugin to test
-->

<div class="panel panel-primary">
  <div class="panel-heading">Metrics Displays Test/Demo</div>
  <div class="panel-body">

    <p>OVMS V3 is based on metrics. Metrics can be single numerical or textual values or complex values
      like sets and arrays. The web framework keeps all metrics in a global object, which can be read
      simply by e.g. <code>metrics["v.b.soc"]</code>.</p>

    <p>Metrics updates (as well as other updates) are sent to all DOM elements having the
      <code>receiver</code> class. To hook into these updates, simply add an event listener for
      <code>msg:metrics</code>. Listening to the event is not necessary if all you need is some metrics
      display. This is covered by the <code>metric</code> class family as shown here.</p>

    <p>
      <button type="button" class="btn btn-default action-gendata">Generate random data</button>
      <button type="button" class="btn btn-default action-showsrc">Show page source</button>
    </p>

    <hr/>

    <div class="receiver">

      <h4>Basic usage</h4>

      <p>All elements of class <code>metric</code> in a <code>receiver</code> are checked for the
        <code>data-metric</code> attribute. If no specific metric class is given, the metric value
        is simply set as the element text: <span class="metric" data-metric="m.net.provider">?</span>
        is your current network provider.</p>

      <h4>Text &amp; Number</h4>

      <p><code>number</code> &amp; <code>text</code> displays get the metric value set in their child of
        class <code>value</code>. They may additionally have labels and units. <code>data-prec</code> can
        be used on <code>number</code> to set the precision, <code>data-scale</code> to scale the raw
        values by a factor. They have fixed min widths and float by default, so you can simply put
        multiple displays into the same container:</p>

      <div class="clearfix">
        <div class="metric number" data-metric="v.e.throttle" data-prec="0">
          <span class="label">Throttle:</span>
          <span class="value">?</span>
          <span class="unit">%</span>
        </div>
        <div class="metric number" data-metric="v.b.12v.voltage.ref" data-prec="1">
          <span class="value">?</span>
          <span class="unit">V<sub>ref</sub></span>
        </div>
        <div class="metric text" data-metric="m.net.provider">
          <span class="label">Network:</span>
          <span class="value">?</span>
        </div>
      </div>

      <h4>Progress Bar</h4>

      <p>Bootstrap <code>progress</code> bars can be used as lightweight graphical indicators.
        Labels and units are available, also <code>data-prec</code> and <code>data-scale</code>.
        Again, all you need is a bit of markup:</p>

      <div class="clearfix">
        <div class="metric progress" data-metric="v.e.throttle" data-prec="0">
          <div class="progress-bar progress-bar-success value-low text-left" role="progressbar"
            aria-valuenow="0" aria-valuemin="0" aria-valuemax="100" style="width:0%">
            <div>
              <span class="label">Throttle:</span>
              <span class="value">?</span>
              <span class="unit">%</span>
            </div>
          </div>
        </div>
        <div class="metric progress" data-metric="v.b.12v.voltage.ref" data-prec="1">
          <div class="progress-bar progress-bar-info value-low text-left" role="progressbar"
            aria-valuenow="0" aria-valuemin="5" aria-valuemax="15" style="width:0%">
            <div>
              <span class="label">12V ref:</span>
              <span class="value">?</span>
              <span class="unit">V</span>
            </div>
          </div>
        </div>
      </div>
  
      <h4>Gauges &amp; Charts</h4>

      <p>The OVMS web framework has builtin support for the highly versatile <b>Highcharts library</b>
        with loads of chart types and options. <code>chart</code> metric examples:</p>

      <div class="row">
        <div class="col-sm-6">
          <div class="metric chart" data-metric="v.e.throttle" style="height:220px">
            <div class="chart-box gaugechart" id="throttle-gauge"/>
          </div>
        </div>
        <div class="col-sm-6">
          <div class="metric chart" data-metric="v.b.c.voltage,v.b.c.voltage.min" style="height:220px">
            <div class="chart-box barchart" id="cell-voltages"/>
          </div>
        </div>
      </div>

      <p><button type="button" class="btn btn-default action-gendata">Generate random data</button></p>

      <p>For charts, a little bit of scripting is necessary.
        The scripts for these charts contain the chart configuration, part of which is the update
        function you need to define. The update function translates metrics data into chart data.
        This is trivial for single values like the throttle, the cell voltage chart is an example
        on basic array processing.</p>

      <p>Also, while charts <em>can</em> be defined with few options, you'll <em>love</em> to explore
        all the features and fine tuning options provided by Highcharts. For inspiration,
        have a look at the <a target="_blank" href="https://www.highcharts.com/demo">Highcharts demos</a>
        and the <a target="_blank" href="https://www.highcharts.com/docs/">Highcharts documentation</a>.
        We're using <a target="_blank" href="https://www.highcharts.com/docs/chart-design-and-style/style-by-css">
        styled mode</a>, so some options don't apply, but everything can be styled by standard CSS.</p>

    </div>

  </div>
</div>

<script>
(function(){

  /* Get page source before chart rendering: */
  var pagesrc = $('#main').html();

  /* Init throttle gauge: */
  $("#throttle-gauge").chart({
    chart: {
      type: 'gauge',
      spacing: [0, 0, 0, 0],
      margin: [0, 0, 0, 0],
      animation: { duration: 500, easing: 'easeOutExpo' },
    },
    title: { text: "Throttle", verticalAlign: "middle", y: 75 },
    credits: { enabled: false },
    tooltip: { enabled: false },
    plotOptions: {
      gauge: { dataLabels: { enabled: false }, overshoot: 1 }
    },
    pane: [{
      startAngle: -125, endAngle: 125, size: '100%', center: ['50%', '60%']
    }],
    yAxis: [{
      title: { text: '%' },
      className: 'throttle',
      reversed: false,
      min: 0, max: 100,
      plotBands: [
        { from: 0, to: 60, className: 'green-band' },
        { from: 60, to: 80, className: 'yellow-band' },
        { from: 80, to: 100, className: 'red-band' },
      ],
      minorTickInterval: 'auto', minorTickLength: 5, minorTickPosition: 'inside',
      tickPixelInterval: 40, tickPosition: 'inside', tickLength: 13,
      labels: { step: 2, distance: -28, x: 0, y: 5, zIndex: 2 },
    }],
    series: [{
      name: 'Throttle', data: [0],
      className: 'throttle',
      animation: { duration: 0 },
      pivot: { radius: '10' },
      dial: { radius: '88%', topWidth: 1, baseLength: '20%', baseWidth: 10, rearLength: '20%' },
    }],
    /* Update method: */
    onUpdate: function(update) {
      // Create gauge data set from metric:
      var data = [ metrics["v.e.throttle"] ];
      // Update chart:
      this.series[0].setData(data);
    },
  });

  /* Init cell voltages chart */
  $("#cell-voltages").chart({
    chart: {
      type: 'column',
      animation: { duration: 500, easing: 'easeOutExpo' },
    },
    title: { text: "Cell Voltages" },
    credits: { enabled: false },
    tooltip: {
      enabled: true,
      shared: true,
      headerFormat: 'Cell #{point.key}:<br/>',
      pointFormat: '{series.name}: <b>{point.y}</b><br/>',
      valueSuffix: " V"
    },
    legend: { enabled: true },
    xAxis: {
      categories: []
    },
    yAxis: [{
      title: { text: null },
      labels: { format: "{value:.2f}V" },
      tickAmount: 4, startOnTick: false, endOnTick: false,
      floor: 3.3, ceiling: 4.2,
      minorTickInterval: 'auto',
    }],
    series: [{
      name: 'Current', data: [],
      className: 'cell-voltage',
      animation: { duration: 0 },
    },{
      name: 'Minimum', data: [],
      className: 'cell-voltage-min',
      animation: { duration: 0 },
    }],
    /* Update method: */
    onUpdate: function(update) {
      // Note: the 'update' parameter contains the actual update set.
      // You can use this to reduce chart updates to the actual changes.
      // For this demo, we just use the global metrics object:
      var
        m_vlt = metrics["v.b.c.voltage"] || [],
        m_min = metrics["v.b.c.voltage.min"] || [];
      // Create categories (cell numbers) & rounded values:
      var cat = [], val0 = [], val1 = [];
      for (var i = 0; i < m_vlt.length; i++) {
        cat.push(i+1);
        val0.push(Number((m_vlt[i]||0).toFixed(3)));
        val1.push(Number((m_min[i]||0).toFixed(3)));
      }
      // Update chart:
      this.xAxis[0].setCategories(cat);
      this.series[0].setData(val0);
      this.series[1].setData(val1);
    },
  });

  /* Test metrics generator: */
  $('.action-gendata').on('click', function() {
    var td = {};
    td["m.net.provider"] = ["hologram","Vodafone","Telekom"][Math.floor(Math.random()*3)];
    td["v.e.throttle"] = Math.random() * 100;
    td["v.b.12v.voltage.ref"] = 10 + Math.random() * 4;
    var m_vlt = [], m_min = [];
    for (var i = 1; i <= 16; i++) {
      m_vlt.push(3.6 + Math.random() * 0.5);
      m_min.push(3.4 + Math.random() * 0.2);
    }
    td["v.b.c.voltage"] = m_vlt;
    td["v.b.c.voltage.min"] = m_min;
    $('.receiver').trigger('msg:metrics', $.extend(metrics, td));
  });

  /* Display page source: */
  $('.action-showsrc').on('click', function() {
    $('<div/>').dialog({
      title: 'Source Code',
      body: '<pre style="font-size:85%; height:calc(100vh - 230px);">'
        + encode_html(pagesrc) + '</pre>',
      size: 'lg',
    });
  });

})();
</script>