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_ - array of axis index to { series : [ series names ] , options : { axis-specific options. }
  15  * series_ - { seriesName -> { idx, yAxis, options }}
  16  * labels_ - used as mapping from index to series name.
  17  */
  18
  19 /**
  20  * This parses attributes into an object that can be easily queried.
  21  *
  22  * It doesn't necessarily mean that all options are available, specifically
  23  * if labels are not yet available, since those drive details of the per-series
  24  * and per-axis options.
  25  *
  26  * @param {Dyraph} dygraph The chart to which these options belong.
  27  * @constructor
  28  */
  29 var DygraphOptions = function(dygraph) {
  30   this.dygraph_ = dygraph;
  31   this.axes_ = [];
  32   this.series_ = {};
  33
  34   // Once these two objects are initialized, you can call get();
  35   this.global_ = this.dygraph_.attrs_;
  36   this.user_ = this.dygraph_.user_attrs_ || {};
  37
  38   this.highlightSeries_ = this.get("highlightSeriesOpts") || {};
  39   // Get a list of series names.
  40
  41   var labels = this.get("labels");
  42   if (!labels) {
  43     return; // -- can't do more for now, will parse after getting the labels.
  44   }
  45
  46   this.reparseSeries();
  47 };
  48
  49 /*
  50  * Not optimal, but does the trick when you're only using two axes.
  51  * If we move to more axes, this can just become a function.
  52  */
  53 DygraphOptions.AXIS_STRING_MAPPINGS_ = {
  54   'y' : 0,
  55   'Y' : 0,
  56   'y1' : 0,
  57   'Y1' : 0,
  58   'y2' : 1,
  59   'Y2' : 1
  60 }
  61
  62 DygraphOptions.axisToIndex_ = function(axis) {
  63   if (typeof(axis) == "string") {
  64     if (DygraphOptions.AXIS_STRING_MAPPINGS_.hasOwnProperty(axis)) {
  65       return DygraphOptions.AXIS_STRING_MAPPINGS_[axis];
  66     }
  67     throw "Unknown axis : " + text;
  68   }
  69   if (typeof(axis) == "number") {
  70     if (axis == 0 || axis == 1) {
  71       return axis;
  72     }
  73     throw "Dygraphs only supports two y-axes, indexed from 0-1."
  74   }
  75   if (axis) {
  76     throw "Unknown axis : " + axis;
  77   }
  78   // No axis specification means axis 0.
  79   return 0;
  80 };
  81
  82 /**
  83  * Reparses options that are all related to series. This typically occurs when
  84  * options are either updated, or source data has been made avaialble.
  85  *
  86  * TODO(konigsberg): The method name is kind of weak; fix.
  87  */
  88 DygraphOptions.prototype.reparseSeries = function() {
  89   this.labels = this.get("labels").slice(1);
  90
  91   this.axes_ = [ { series : [], options : {}} ]; // Always one axis at least.
  92   this.series_ = {};
  93
  94   // Traditionally, per-series options were specified right up there with the options. For instance
  95   // {
  96   //   labels: [ "X", "foo", "bar" ],
  97   //   pointSize: 3,
  98   //   foo : {}, // options for foo
  99   //   bar : {} // options for bar
 100   // }
 101   //
 102   // Moving forward, series really should be specified in the series element, separating them.
 103   // like so:
 104   //
 105   // {
 106   //   labels: [ "X", "foo", "bar" ],
 107   //   pointSize: 3,
 108   //   series : {
 109   //     foo : {}, // options for foo
 110   //     bar : {} // options for bar
 111   //   }
 112   // }
 113   //
 114   // So, if series is found, it's expected to contain per-series data, otherwise we fall
 115   // back.
 116   var oldStyleSeries = !this.user_["series"];
 117
 118   if (oldStyleSeries) {
 119     var axisId = 0; // 0-offset; there's always one.
 120     // Go through once, add all the series, and for those with {} axis options, add a new axis.
 121     for (var idx = 0; idx < this.labels.length; idx++) {
 122       var seriesName = this.labels[idx];
 123
 124       var optionsForSeries = this.user_[seriesName] || {};
 125
 126       var yAxis = 0;
 127       var axis = optionsForSeries["axis"];
 128       if (typeof(axis) == 'object') {
 129         yAxis = ++axisId;
 130         this.axes_[yAxis] = { series : [ seriesName ], options : axis };
 131       }
 132
 133       // Associate series without axis options with axis 0.
 134       if (!axis) { // undefined
 135         this.axes_[0].series.push(seriesName);
 136       }
 137
 138       this.series_[seriesName] = { idx: idx, yAxis: yAxis, options : optionsForSeries };
 139     }
 140
 141     // Go through one more time and assign series to an axis defined by another
 142     // series, e.g. { 'Y1: { axis: {} }, 'Y2': { axis: 'Y1' } }
 143     for (var idx = 0; idx < this.labels.length; idx++) {
 144       var seriesName = this.labels[idx];
 145       var optionsForSeries = this.series_[seriesName]["options"];
 146       var axis = optionsForSeries["axis"];
 147
 148       if (typeof(axis) == 'string') {
 149         if (!this.series_.hasOwnProperty(axis)) {
 150           this.dygraph_.error("Series " + seriesName + " wants to share a y-axis with " +
 151                      "series " + axis + ", which does not define its own axis.");
 152           return null;
 153         }
 154         var yAxis = this.series_[axis].yAxis;
 155         this.series_[seriesName].yAxis = yAxis;
 156         this.axes_[yAxis].series.push(seriesName);
 157       }
 158     }
 159   } else {
 160     for (var idx = 0; idx < this.labels.length; idx++) {
 161       var seriesName = this.labels[idx];
 162       var optionsForSeries = this.user_.series[seriesName] || {};
 163       var yAxis = DygraphOptions.axisToIndex_(optionsForSeries["axis"]);
 164
 165       this.series_[seriesName] = {
 166         idx: idx,
 167         yAxis: yAxis,
 168         options : optionsForSeries };
 169
 170       if (!this.axes_[yAxis]) {
 171         this.axes_[yAxis] =  { series : [ seriesName ], options : {} };
 172       } else {
 173         this.axes_[yAxis].series.push(seriesName);
 174       }
 175     }
 176   }
 177
 178   // This doesn't support reading from the 'x' axis, only 'y' and 'y2.
 179   var axis_opts = this.user_["axes"] || {};
 180   Dygraph.update(this.axes_[0].options, axis_opts["y"] || {});
 181   if (this.axes_.length > 1) {
 182     Dygraph.update(this.axes_[1].options, axis_opts["y2"] || {});
 183   }
 184 };
 185
 186 /**
 187  * Get a global value.
 188  *
 189  * @param {String} name the name of the option.
 190  */
 191 DygraphOptions.prototype.get = function(name) {
 192   if (this.user_.hasOwnProperty(name)) {
 193     return this.user_[name];
 194   }
 195   if (this.global_.hasOwnProperty(name)) {
 196     return this.global_[name];
 197   }
 198   return null;
 199 };
 200
 201 /**
 202  * Get a value for a specific axis. If there is no specific value for the axis,
 203  * the global value is returned.
 204  *
 205  * @param {String} name the name of the option.
 206  * @param {String|number} axis the axis to search. Can be the string representation
 207  * ("y", "y2") or the axis number (0, 1).
 208  */
 209 DygraphOptions.prototype.getForAxis = function(name, axis) {
 210   var axisIdx = 0;
 211   if (typeof(axis) == 'number') {
 212     axisIdx = axis;
 213   } else {
 214     // TODO(konigsberg): Accept only valid axis strings?
 215     axisIdx = (axis == "y2") ? 1 : 0;
 216   }
 217
 218   var axisOptions = this.axes_[axisIdx].options;
 219   if (axisOptions.hasOwnProperty(name)) {
 220     return axisOptions[name];
 221   }
 222   return this.get(name);
 223 };
 224
 225 /**
 226  * Get a value for a specific series. If there is no specific value for the series,
 227  * the value for the axis is returned (and afterwards, the global value.)
 228  *
 229  * @param {String} name the name of the option.
 230  * @param {String|number} series the series to search. Can be the string representation
 231  * or 0-offset series number.
 232  */
 233 DygraphOptions.prototype.getForSeries = function(name, series) {
 234   // Honors indexes as series.
 235   var seriesName = (typeof(series) == "number") ? this.labels[series] : series;
 236
 237   if (seriesName === this.dygraph_.highlightSet_) {
 238     if (this.highlightSeries_.hasOwnProperty(name)) {
 239       return this.highlightSeries_[name];
 240     }
 241   }
 242
 243   if (!this.series_.hasOwnProperty(seriesName)) {
 244     throw "Unknown series: " + series;
 245   }
 246
 247   var seriesObj = this.series_[seriesName];
 248   var seriesOptions = seriesObj["options"];
 249   if (seriesOptions.hasOwnProperty(name)) {
 250     return seriesOptions[name];
 251   }
 252
 253   return this.getForAxis(name, seriesObj["yAxis"]);
 254 };
 255
 256 /**
 257  * Returns the number of y-axes on the chart.
 258  * @return {Number} the number of axes.
 259  */
 260 DygraphOptions.prototype.numAxes = function() {
 261   return this.axes_.length;
 262 }
 263
 264 /**
 265  * Return the y-axis for a given series, specified by name.
 266  */
 267 DygraphOptions.prototype.axisForSeries = function(seriesName) {
 268   return this.series_[seriesName].yAxis;
 269 }
 270
 271 /**
 272  * Returns the options for the specified axis.
 273  */
 274 DygraphOptions.prototype.axisOptions = function(yAxis) {
 275   return this.axes_[yAxis].options;
 276 }
 277
 278 /**
 279  * Return the series associated with an axis.
 280  */
 281 DygraphOptions.prototype.seriesForAxis = function(yAxis) {
 282   return this.axes_[yAxis].series;
 283 }
 284
 285 /**
 286  * Return the list of all series, in their columnar order.
 287  */
 288 DygraphOptions.prototype.seriesNames = function() {
 289   return this.labels_;
 290 }
 291
 292 /* Are we using this? */
 293 /**
 294  * Return the index of the specified series.
 295  * @param {string} series the series name.
 296  */
 297 DygraphOptions.prototype.indexOfSeries = function(series) {
 298   return this.series_[series].idx;
 299 }