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  * yAxes_ - array of axis index to { series : [ series names ] , options : { axis-specific options. }
  15  * xAxis_ - { options : { axis-specific options. }
  16  * series_ - { seriesName -> { idx, yAxis, options }}
  17  * labels_ - used as mapping from index to series name.
  18  */
  19
  20 /**
  21  * This parses attributes into an object that can be easily queried.
  22  *
  23  * It doesn't necessarily mean that all options are available, specifically
  24  * if labels are not yet available, since those drive details of the per-series
  25  * and per-axis options.
  26  *
  27  * @param {Dyraph} dygraph The chart to which these options belong.
  28  * @constructor
  29  */
  30 var DygraphOptions = function(dygraph) {
  31   this.dygraph_ = dygraph;
  32   this.yAxes_ = [];
  33   this.xAxis_ = {};
  34   this.series_ = {};
  35
  36   // Once these two objects are initialized, you can call get();
  37   this.global_ = this.dygraph_.attrs_;
  38   this.user_ = this.dygraph_.user_attrs_ || {};
  39
  40   this.highlightSeries_ = this.get("highlightSeriesOpts") || {};
  41   // Get a list of series names.
  42
  43   var labels = this.get("labels");
  44   if (!labels) {
  45     return; // -- can't do more for now, will parse after getting the labels.
  46   }
  47
  48   this.reparseSeries();
  49 };
  50
  51 /*
  52  * Not optimal, but does the trick when you're only using two axes.
  53  * If we move to more axes, this can just become a function.
  54  */
  55 DygraphOptions.AXIS_STRING_MAPPINGS_ = {
  56   'y' : 0,
  57   'Y' : 0,
  58   'y1' : 0,
  59   'Y1' : 0,
  60   'y2' : 1,
  61   'Y2' : 1
  62 };
  63
  64 DygraphOptions.axisToIndex_ = function(axis) {
  65   if (typeof(axis) == "string") {
  66     if (DygraphOptions.AXIS_STRING_MAPPINGS_.hasOwnProperty(axis)) {
  67       return DygraphOptions.AXIS_STRING_MAPPINGS_[axis];
  68     }
  69     throw "Unknown axis : " + axis;
  70   }
  71   if (typeof(axis) == "number") {
  72     if (axis === 0 || axis === 1) {
  73       return axis;
  74     }
  75     throw "Dygraphs only supports two y-axes, indexed from 0-1.";
  76   }
  77   if (typeof(axis) == "object") {
  78     throw "Using objects for axis specification "
  79       + "is not supported inside the 'series' option.";
  80   }
  81   if (axis) {
  82     throw "Unknown axis : " + axis;
  83   }
  84   // No axis specification means axis 0.
  85   return 0;
  86 };
  87
  88 /**
  89  * Reparses options that are all related to series. This typically occurs when
  90  * options are either updated, or source data has been made avaialble.
  91  *
  92  * TODO(konigsberg): The method name is kind of weak; fix.
  93  */
  94 DygraphOptions.prototype.reparseSeries = function() {
  95   this.labels = this.get("labels").slice(1);
  96
  97   this.yAxes_ = [ { series : [], options : {}} ]; // Always one axis at least.
  98   this.xAxis_ = { options : {} };
  99   this.series_ = {};
 100
 101   // Traditionally, per-series options were specified right up there with the options. For instance
 102   // {
 103   //   labels: [ "X", "foo", "bar" ],
 104   //   pointSize: 3,
 105   //   foo : {}, // options for foo
 106   //   bar : {} // options for bar
 107   // }
 108   //
 109   // Moving forward, series really should be specified in the series element, separating them.
 110   // like so:
 111   //
 112   // {
 113   //   labels: [ "X", "foo", "bar" ],
 114   //   pointSize: 3,
 115   //   series : {
 116   //     foo : {}, // options for foo
 117   //     bar : {} // options for bar
 118   //   }
 119   // }
 120   //
 121   // So, if series is found, it's expected to contain per-series data, otherwise we fall
 122   // back.
 123   var oldStyleSeries = !this.user_["series"];
 124
 125   if (oldStyleSeries) {
 126     var axisId = 0; // 0-offset; there's always one.
 127     // Go through once, add all the series, and for those with {} axis options, add a new axis.
 128     for (var idx = 0; idx < this.labels.length; idx++) {
 129       var seriesName = this.labels[idx];
 130
 131       var optionsForSeries = this.user_[seriesName] || {};
 132
 133       var yAxis = 0;
 134       var axis = optionsForSeries["axis"];
 135       if (typeof(axis) == 'object') {
 136         yAxis = ++axisId;
 137         this.yAxes_[yAxis] = { series : [ seriesName ], options : axis };
 138       }
 139
 140       // Associate series without axis options with axis 0.
 141       if (!axis) { // undefined
 142         this.yAxes_[0].series.push(seriesName);
 143       }
 144
 145       this.series_[seriesName] = { idx: idx, yAxis: yAxis, options : optionsForSeries };
 146     }
 147
 148     // Go through one more time and assign series to an axis defined by another
 149     // series, e.g. { 'Y1: { axis: {} }, 'Y2': { axis: 'Y1' } }
 150     for (var idx = 0; idx < this.labels.length; idx++) {
 151       var seriesName = this.labels[idx];
 152       var optionsForSeries = this.series_[seriesName]["options"];
 153       var axis = optionsForSeries["axis"];
 154
 155       if (typeof(axis) == 'string') {
 156         if (!this.series_.hasOwnProperty(axis)) {
 157           this.dygraph_.error("Series " + seriesName + " wants to share a y-axis with " +
 158                      "series " + axis + ", which does not define its own axis.");
 159           return null;
 160         }
 161         var yAxis = this.series_[axis].yAxis;
 162         this.series_[seriesName].yAxis = yAxis;
 163         this.yAxes_[yAxis].series.push(seriesName);
 164       }
 165     }
 166   } else {
 167     for (var idx = 0; idx < this.labels.length; idx++) {
 168       var seriesName = this.labels[idx];
 169       var optionsForSeries = this.user_.series[seriesName] || {};
 170       var yAxis = DygraphOptions.axisToIndex_(optionsForSeries["axis"]);
 171
 172       this.series_[seriesName] = {
 173         idx: idx,
 174         yAxis: yAxis,
 175         options : optionsForSeries };
 176
 177       if (!this.yAxes_[yAxis]) {
 178         this.yAxes_[yAxis] =  { series : [ seriesName ], options : {} };
 179       } else {
 180         this.yAxes_[yAxis].series.push(seriesName);
 181       }
 182     }
 183   }
 184
 185   var axis_opts = this.user_["axes"] || {};
 186   Dygraph.update(this.yAxes_[0].options, axis_opts["y"] || {});
 187   if (this.yAxes_.length > 1) {
 188     Dygraph.update(this.yAxes_[1].options, axis_opts["y2"] || {});
 189   }
 190   Dygraph.update(this.xAxis_.options, axis_opts["x"] || {});
 191 };
 192
 193 /**
 194  * Get a global value.
 195  *
 196  * @param {String} name the name of the option.
 197  */
 198 DygraphOptions.prototype.get = function(name) {
 199   var result = this.getGlobalUser_(name);
 200   if (result != null) {
 201     return result;
 202   }
 203   return this.getGlobalDefault_(name);
 204 };
 205
 206 DygraphOptions.prototype.getGlobalUser_ = function(name) {
 207   if (this.user_.hasOwnProperty(name)) {
 208     return this.user_[name];
 209   }
 210   return null;
 211 };
 212
 213 DygraphOptions.prototype.getGlobalDefault_ = function(name) {
 214   if (this.global_.hasOwnProperty(name)) {
 215     return this.global_[name];
 216   }
 217   if (Dygraph.DEFAULT_ATTRS.hasOwnProperty(name)) {
 218     return Dygraph.DEFAULT_ATTRS[name];
 219   }
 220   return null;
 221 }
 222
 223 /**
 224  * Get a value for a specific axis. If there is no specific value for the axis,
 225  * the global value is returned.
 226  *
 227  * @param {String} name the name of the option.
 228  * @param {String|number} axis the axis to search. Can be the string representation
 229  * ("x", "y", "y2") or the y-axis number (0, 1). (x-axis can't be specified by number.')
 230  */
 231 DygraphOptions.prototype.getForAxis = function(name, axis) {
 232   var axisIdx;
 233   var axisString;
 234
 235   // Since axis can be a number or a string, straighten everything out here.
 236   if (typeof(axis) == 'number') {
 237     axisIdx = axis;
 238     axisString = axisIdx == 0 ? "y" : "y2";
 239   } else {
 240     if (axis == "y1") { axis = "y"; } // Standardize on 'y'. Is this bad? I think so.
 241     if (axis == "y") {
 242       axisIdx = 0;
 243     } else if (axis == "y2") {
 244       axisIdx = 1;
 245     } else if (axis == "x") {
 246       axisIdx = -1; // simply a placeholder for below.
 247     } else {
 248       throw "Unknown axis " + axis;
 249     }
 250     axisString = axis;
 251   }
 252
 253   var userAxis = (axisIdx == -1) ? this.xAxis_ : this.yAxes_[axisIdx];
 254
 255   // Search the user-specified axis option first.
 256   if (userAxis) { // This condition could be removed if we always set up this.yAxes_ for y2.
 257     var axisOptions = userAxis.options;
 258     if (axisOptions.hasOwnProperty(name)) {
 259       return axisOptions[name];
 260     }
 261   }
 262
 263   // User-specified global options second.
 264   var result = this.getGlobalUser_(name);
 265   if (result != null) {
 266     return result;
 267   }
 268
 269   // Default axis options third.
 270   var defaultAxisOptions = Dygraph.DEFAULT_ATTRS.axes[axisString];
 271   if (defaultAxisOptions.hasOwnProperty(name)) {
 272     return defaultAxisOptions[name];
 273   }
 274
 275   // Default global options last.
 276   return this.getGlobalDefault_(name);
 277 };
 278
 279 /**
 280  * Get a value for a specific series. If there is no specific value for the series,
 281  * the value for the axis is returned (and afterwards, the global value.)
 282  *
 283  * @param {String} name the name of the option.
 284  * @param {String|number} series the series to search. Can be the string representation
 285  * or 0-offset series number.
 286  */
 287 DygraphOptions.prototype.getForSeries = function(name, series) {
 288   // Honors indexes as series.
 289   var seriesName = (typeof(series) == "number") ? this.labels[series] : series;
 290
 291   if (seriesName === this.dygraph_.highlightSet_) {
 292     if (this.highlightSeries_.hasOwnProperty(name)) {
 293       return this.highlightSeries_[name];
 294     }
 295   }
 296
 297   if (!this.series_.hasOwnProperty(seriesName)) {
 298     throw "Unknown series: " + series;
 299   }
 300
 301   var seriesObj = this.series_[seriesName];
 302   var seriesOptions = seriesObj["options"];
 303   if (seriesOptions.hasOwnProperty(name)) {
 304     return seriesOptions[name];
 305   }
 306
 307   return this.getForAxis(name, seriesObj["yAxis"]);
 308 };
 309
 310 /**
 311  * Returns the number of y-axes on the chart.
 312  * @return {Number} the number of axes.
 313  */
 314 DygraphOptions.prototype.numAxes = function() {
 315   return this.yAxes_.length;
 316 };
 317
 318 /**
 319  * Return the y-axis for a given series, specified by name.
 320  */
 321 DygraphOptions.prototype.axisForSeries = function(seriesName) {
 322   return this.series_[seriesName].yAxis;
 323 };
 324
 325 /**
 326  * Returns the options for the specified axis.
 327  */
 328 // TODO(konigsberg): this is y-axis specific. Support the x axis.
 329 DygraphOptions.prototype.axisOptions = function(yAxis) {
 330   return this.yAxes_[yAxis].options;
 331 };
 332
 333 /**
 334  * Return the series associated with an axis.
 335  */
 336 DygraphOptions.prototype.seriesForAxis = function(yAxis) {
 337   return this.yAxes_[yAxis].series;
 338 };
 339
 340 /**
 341  * Return the list of all series, in their columnar order.
 342  */
 343 DygraphOptions.prototype.seriesNames = function() {
 344   return this.labels_;
 345 };
 346
 347 /* Are we using this? */
 348 /**
 349  * Return the index of the specified series.
 350  * @param {string} series the series name.
 351  */
 352 DygraphOptions.prototype.indexOfSeries = function(series) {
 353   return this.series_[series].idx;
 354 };