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  * global_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.global_user = this.dygraph_.user_attrs_ || {};
  34
  35   // Get a list of series names.
  36
  37   var labels = this.find("labels");
  38   if (!labels) {
  39     return; // -- can't do more for now, will parse after getting the labels.
  40   };
  41
  42   this.reparseSeries();
  43 }
  44
  45 DygraphOptions.prototype.reparseSeries = function() {
  46   this.labels = this.find("labels").slice(1);
  47
  48   this.axes = [ {} ]; // Always one axis at least.
  49   this.series = {};
  50
  51   var axisId = 0; // 0-offset; there's always one.
  52   // Go through once, add all the series, and for those with {} axis options, add a new axis.
  53   for (var idx = 0; idx < this.labels.length; idx++) {
  54     var seriesName = this.labels[idx];
  55
  56     var optionsForSeries = this.global_user[seriesName] || {};
  57     var yAxis = 0;
  58
  59     var axis = optionsForSeries["axis"];
  60     if (typeof(axis) == 'object') {
  61       yAxis = ++axisId;
  62       this.axes[yAxis] = axis;
  63     }
  64     this.series[seriesName] = { idx: idx, yAxis: yAxis, options : optionsForSeries };
  65   }
  66
  67   // Go through one more time and assign series to an axis defined by another
  68   // series, e.g. { 'Y1: { axis: {} }, 'Y2': { axis: 'Y1' } }
  69   for (var idx = 0; idx < this.labels.length; idx++) {
  70     var seriesName = this.labels[idx];
  71     var optionsForSeries = this.series[seriesName]["options"];
  72     var axis = optionsForSeries["axis"];
  73
  74     if (typeof(axis) == 'string') {
  75       if (!this.series.hasOwnProperty(axis)) {
  76         this.dygraph_.error("Series " + seriesName + " wants to share a y-axis with " +
  77                    "series " + axis + ", which does not define its own axis.");
  78         return null;
  79       }
  80       this.series[seriesName].yAxis = this.series[axis].yAxis;
  81     }
  82   }
  83
  84   // This doesn't support reading from the 'x' axis, only 'y' and 'y2.
  85   // Read from the global "axes" option.
  86   if (this.global_user.hasOwnProperty("axes")) {
  87     var axis_opts = this.global_user.axes;
  88
  89     if (axis_opts.hasOwnProperty("y")) {
  90       Dygraph.update(this.axes[0], axis_opts.y);
  91     }
  92
  93     if (axis_opts.hasOwnProperty("y2")) {
  94       this.axes[1] = this.axes[1] || {};
  95       Dygraph.update(this.axes[1], axis_opts.y2);
  96     }
  97   }
  98 };
  99
 100 DygraphOptions.prototype.find = function(name) {
 101   if (this.global_user.hasOwnProperty(name)) {
 102     return this.global_user[name];
 103   }
 104   if (this.global.hasOwnProperty(name)) {
 105     return this.global[name];
 106   }
 107   return null;
 108 }
 109
 110 DygraphOptions.prototype.findForAxis = function(name, axis) {
 111
 112   var axisIdx = (axis == "y2" || axis == "y2" || axis == 1) ? 1 : 0;
 113
 114   var axisOptions = this.axes[axisIdx];
 115   if (axisOptions.hasOwnProperty(name)) {
 116     return axisOptions[name];
 117   }
 118   return this.find(name);
 119 }
 120
 121 DygraphOptions.prototype.findForSeries = function(name, series) {
 122   // Honors indexes as series.
 123   var seriesName = (typeof(series) == "number") ? this.labels[series] : series;
 124
 125   if (!this.series.hasOwnProperty(seriesName)) {
 126     throw "Unknown series: " + series;
 127   }
 128
 129   var seriesObj = this.series[seriesName];
 130   var seriesOptions = seriesObj["options"];
 131   if (seriesOptions.hasOwnProperty(name)) {
 132     return seriesOptions[name];
 133   }
 134   return this.findForAxis(name, seriesObj["yAxis"]);
 135 }
 136