ArgusPlusGoogleCharts.js

// class for any valid Argus metric expression
function ArgusData(urlBase, validMetricExploreExpression){
    this.base = urlBase + "/argusws/metrics?expression=",
    this.expression = validMetricExploreExpression,
    this.url = this.base + this.expression,
    this.queryArgus.bind(this), // IIFE to initalize this.dataTable
    this.pivotView = function(precision, groupColNum, filterValue, valueColNum){
          // helper
          function round(value, decimals) {
            return Number(Math.round(value+'e'+decimals)+'e-'+decimals);
          }

        // create a list of cols to pivot on (if filtered, just use that filter)
        var distinctValues = filterValue ? [filterValue] : this.dataTable.getDistinctValues(groupColNum);
        var viewColumns = [0]; // primary key for each row is col 0
        var groupColumns = [];
        // build column arrays for the view and grouping
        // col 6 has the keys (Argus tags), col 7 has the values
        for (var i = 0; i < distinctValues.length; i++) {
          viewColumns.push({
            type: 'number',
            label: distinctValues[i],
            calc: (function(x) {
              return function(dt, row) {
                return (dt.getValue(row, groupColNum) == x) ?
                  round(dt.getValue(row, valueColNum),precision) : null;
              }
            })(distinctValues[i])
          });
          groupColumns.push({
            column: i + 1,
            type: 'number',
            label: distinctValues[i],
            aggregation: google.visualization.data.sum
          });
        } // for

        var view = new google.visualization.DataView(this.dataTable);
        view.setColumns(viewColumns);

        return google.visualization.data.group(view, [0], groupColumns);
    }
}

// helper to round values without rounding errors
function round(value, decimals) {
  return Number(Math.round(value+'e'+decimals)+'e-'+decimals);
}

// helper to get selected column label from pivotView to support drill downs
function getLabel(dataView, sel){

  if (sel.length == 0){
    return '*';
  } else {
    return dataView.getColumnLabel(sel[0].column);
  }
}; // getLabel

// helper to pivot Google DataTable given key and value columns
// necessary to create series data for LineChart, AreaChart, etc.
function createPivotView(dataTable, precision, groupColNum, filterValue, valueColNum){
  // create a list of cols to pivot on (if filtered, just use that filter)
  var distinctValues = filterValue ? [filterValue] : dataTable.getDistinctValues(groupColNum);
  var viewColumns = [0]; // primary key for each row is col 0
  var groupColumns = [];
  // build column arrays for the view and grouping
  // col 6 has the keys (Argus tags), col 7 has the values
  for (var i = 0; i < distinctValues.length; i++) {
    viewColumns.push({
      type: 'number',
      label: distinctValues[i],
      calc: (function(x) {
        return function(dt, row) {
          return (dt.getValue(row, groupColNum) == x) ?
            round(dt.getValue(row, valueColNum),precision) : null;
        }
      })(distinctValues[i])
    });
    groupColumns.push({
      column: i + 1,
      type: 'number',
      label: distinctValues[i],
      aggregation: google.visualization.data.sum
    });
  } // for

  var view = new google.visualization.DataView(dataTable);
  view.setColumns(viewColumns);

  return google.visualization.data.group(view, [0], groupColumns);

} // createPivotView

// load the rest of the dependencies 
function loadRest(){
  google.charts.load('current'); // no packages, requires use of ChartWrapper

  ArgusData.prototype.queryArgus = function(e){
      var deferred = Q.defer();
      $.ajax({
        url: e.url,
        async: true,
        crossDomain: true,
        dataType: 'json',
        xhrFields: {
          withCredentials: true
        },
        success: function (data) {
          console.log("Data retrieved.")
          // always create new dataTable
          e.dataTable = new google.visualization.DataTable();
          // set the header row
          e.dataTable.addColumn('date', 'timestamp');
          e.dataTable.addColumn('string', 'namespace');
          e.dataTable.addColumn('string', 'scope');
          e.dataTable.addColumn('string', 'metric');
          e.dataTable.addColumn('string', 'displayName');
          e.dataTable.addColumn('string', 'units');
          // handle variable number of tags
          $.each(Object.keys(data[0].tags), function(key,value){
            e.dataTable.addColumn('string', value);
          });
          e.dataTable.addColumn('number', 'value');

          //console.log(Object.keys(data[0].tags));

          // outer loop to create the rows
          for (var i = 0; i < data.length; i++) {
            var dataPoints = Object.entries(data[i].datapoints);
            // inner loop to create a row for every datapoint (timestamp/value)
            dataPoints.forEach(function(element) {
              var row = [];
              row.push(new Date(Number(element[0])));
              row.push(data[i].namespace || "global");
              row.push(data[i].scope);
              row.push(data[i].metric);
              row.push(data[i].displayName || data[i].metric);
              row.push(data[i].units || "unknown");
              // handle variable number of tags
              $.each(Object.values(data[i].tags), function(key,value){
                row.push(value);
              });
              row.push(Number(element[1]));
              e.dataTable.addRow(row);
            });
          }
          deferred.resolve();
        }
      })
    return deferred.promise;
  }
}