dygraph-options.js

   1 /**
   2  * @fileoverview DygraphOptions is responsible for parsing and returning information about options.
   3  *
   4  * Still tightly coupled to Dygraphs, we could remove some of that, you know.
   5  */
   6
   7 "use strict";
   8
   9 /*
  10  * Interesting member variables:
  11  * dygraph_ - the graph.
  12  * global - global attributes (common among all graphs, AIUI)
  13  * user - attributes set by the user
  14  * axes
  15  * series - { seriesName -> { idx, yAxis, options }
  16  * labels - used as mapping from index to series name.
  17  */
  18
  19 /**
  20  * @constructor
  21  *
  22  * This parses attributes into an object that can be easily queried.
  23  *
  24  * @param {Dyraph} dygraph The chart to which these options belong.
  25  */
  26 var DygraphOptions = function(dygraph) {
  27   this.dygraph_ = dygraph;
  28   this.axes_ = [];
  29   this.series_ = {};
  30
  31   // Once these two objects are initialized, you can call find();
  32   this.global_ = this.dygraph_.attrs_;
  33   this.user_ = this.dygraph_.user_attrs_ || {};
  34
  35   this.highlightSeries_ = this.find("highlightSeriesOpts") || {};
  36   // Get a list of series names.
  37
  38   var labels = this.find("labels");
  39   if (!labels) {
  40     return; // -- can't do more for now, will parse after getting the labels.
  41   };
  42
  43   this.reparseSeries();
  44 }
  45
  46 DygraphOptions.prototype.reparseSeries = function() {
  47   this.labels = this.find("labels").slice(1);
  48
  49   this.axes_ = [ {} ]; // Always one axis at least.
  50   this.series_ = {};
  51
  52   // Traditionally, per-series options were specified right up there with the options. For instance
  53   // {
  54   //   labels: [ "X", "foo", "bar" ],
  55   //   pointSize: 3,
  56   //   foo : {}, // options for foo
  57   //   bar : {} // options for bar
  58   // }
  59   //
  60   // Moving forward, series really should be specified in the series element, separating them.
  61   // like so:
  62   //
  63   // {
  64   //   labels: [ "X", "foo", "bar" ],
  65   //   pointSize: 3,
  66   //   series : {
  67   //     foo : {}, // options for foo
  68   //     bar : {} // options for bar
  69   //   }
  70   // }
  71   //
  72   // So, if series is found, it's expected to contain per-series data, otherwise we fall
  73   // back.
  74   var allseries = this.user_.hasOwnProperty("series") ? this.user_.series : this.user_;
  75
  76   var axisId = 0; // 0-offset; there's always one.
  77   // Go through once, add all the series, and for those with {} axis options, add a new axis.
  78   for (var idx = 0; idx < this.labels.length; idx++) {
  79     var seriesName = this.labels[idx];
  80
  81     var optionsForSeries = allseries[seriesName] || {};
  82     var yAxis = 0;
  83
  84     var axis = optionsForSeries["axis"];
  85     if (typeof(axis) == 'object') {
  86       yAxis = ++axisId;
  87       this.axes_[yAxis] = axis;
  88     }
  89     this.series_[seriesName] = { idx: idx, yAxis: yAxis, options : optionsForSeries };
  90   }
  91
  92   // Go through one more time and assign series to an axis defined by another
  93   // series, e.g. { 'Y1: { axis: {} }, 'Y2': { axis: 'Y1' } }
  94   for (var idx = 0; idx < this.labels.length; idx++) {
  95     var seriesName = this.labels[idx];
  96     var optionsForSeries = this.series_[seriesName]["options"];
  97     var axis = optionsForSeries["axis"];
  98
  99     if (typeof(axis) == 'string') {
 100       if (!this.series_.hasOwnProperty(axis)) {
 101         this.dygraph_.error("Series " + seriesName + " wants to share a y-axis with " +
 102                    "series " + axis + ", which does not define its own axis.");
 103         return null;
 104       }
 105       this.series_[seriesName].yAxis = this.series_[axis].yAxis;
 106     }
 107   }
 108
 109   // This doesn't support reading from the 'x' axis, only 'y' and 'y2.
 110   // Read from the global "axes" option.
 111   if (this.user_.hasOwnProperty("axes")) {
 112     var axis_opts = this.user_.axes;
 113
 114     if (axis_opts.hasOwnProperty("y")) {
 115       Dygraph.update(this.axes_[0], axis_opts.y);
 116     }
 117
 118     if (axis_opts.hasOwnProperty("y2")) {
 119       this.axes_[1] = this.axes_[1] || {};
 120       Dygraph.update(this.axes_[1], axis_opts.y2);
 121     }
 122   }
 123 };
 124
 125 DygraphOptions.prototype.find = function(name) {
 126   if (this.user_.hasOwnProperty(name)) {
 127     return this.user_[name];
 128   }
 129   if (this.global_.hasOwnProperty(name)) {
 130     return this.global_[name];
 131   }
 132   return null;
 133 }
 134
 135 DygraphOptions.prototype.findForAxis = function(name, axis) {
 136   var axisIdx = (axis == "y2" || axis == "y2" || axis == 1) ? 1 : 0;
 137
 138   var axisOptions = this.axes_[axisIdx];
 139   if (axisOptions.hasOwnProperty(name)) {
 140     return axisOptions[name];
 141   }
 142   return this.find(name);
 143 }
 144
 145 DygraphOptions.prototype.findForSeries = function(name, series) {
 146   // Honors indexes as series.
 147   var seriesName = (typeof(series) == "number") ? this.labels[series] : series;
 148
 149   if (seriesName === this.dygraph_.highlightSet_) {
 150     if (this.highlightSeries_.hasOwnProperty(name)) {
 151       return this.highlightSeries_[name];
 152     }
 153   }
 154
 155   if (!this.series_.hasOwnProperty(seriesName)) {
 156     throw "Unknown series: " + series;
 157   }
 158
 159   var seriesObj = this.series_[seriesName];
 160   var seriesOptions = seriesObj["options"];
 161   if (seriesOptions.hasOwnProperty(name)) {
 162     return seriesOptions[name];
 163   }
 164
 165   return this.findForAxis(name, seriesObj["yAxis"]);
 166 }
 167