extract time functions

Author: jjasonclark

lib/providers/metrics-provider.js

@@ -7,9 +7,9 @@
 var EventEmitter = require("events").EventEmitter;
 var _ = require("lodash");
 var constants = require("../constants");
+var time = require("../time");
 
 // get the defined aggregation levels
-var TIME_SCALES = constants.TIME_SCALES;
 var AGGREGATE_TIME_LEVELS = constants.AGGREGATE_TIME_LEVELS;
 
 // what a valid time offset looks like
@@ -79,177 +79,6 @@ var MetricsProvider =
 // MetricsProvider inherits from EventEmitter
 MetricsProvider.prototype = Object.create(EventEmitter.prototype);
 
-/**
- * Given a time index and unit of time measure, compute a condensed, human-readable label.
- *
- * @param {Number} timeIndex
- * The logical index of time.
- *
- * @param {Number} aggregateTimeUnits
- * The unit of time measure.
- *
- * @returns {String}
- * A scaled, string-representation of time at the index is returned.
- */
-var getTimeIndexLabel =
-  function getTimeIndexLabel(timeIndex, aggregateTimeUnits) {
-    var DIGITS_PER_UNIT = 2;
-
-    var timeValue = timeIndex * aggregateTimeUnits;
-    var timeElements = [];
-
-    if (timeValue === 0) {
-      return ":00";
-    }
-
-    _.every(TIME_SCALES, function (timeScale, index, timeScales) {
-      var timeElement = {
-        units: timeScale.units,
-        value: 0
-      };
-
-      // stop reducing when it cannot be divided
-      if (timeValue < timeScale.divisor) {
-        return false;
-      }
-
-      // don't capture a time element for milliseconds
-      if (timeScale.units !== "ms") {
-        // reduce by the divisor
-        timeElement.value = timeValue / timeScale.divisor;
-
-        // if there are more elements after, take the modulo to get the remainder
-        if (index < timeScales.length - 1) {
-          timeElement.value = Math.floor(timeElement.value % timeScales[index + 1].divisor);
-        } else {
-          timeElement.value = Math.floor(timeElement.value);
-        }
-
-        timeElements.push(timeElement);
-      }
-
-      // reduce
-      timeValue /= timeScale.divisor;
-
-      return true;
-    });
-
-    return _.reduce(timeElements, function (prev, curr, index) {
-      switch (curr.units) {
-      case "s":
-        return ":" + _.padStart(curr.value, DIGITS_PER_UNIT, "0");
-      case "m":
-      case "h":
-        if (index < timeElements.length - 1) {
-          return (curr.units === "m" ? ":" : " ")
-            + _.padStart(curr.value, DIGITS_PER_UNIT, "0")
-            + prev;
-        } else {
-          return curr.value + prev;
-        }
-      default:
-        return curr.value + curr.units + prev;
-      }
-    }, "");
-  };
-
-/**
- * Given a time label value (ex: 2y 5d 1:22:33), produce the actual
- * time value in ms.
- *
- * @param {String} label
- * The time label to convert.
- *
- * @throws {Error}
- * An error is thrown if the time label cannot be converted to ms.
- *
- * @returns {Number}
- * The time value in ms is returned.
- */
-var convertTimeLabelToMilliseconds = function (label) {
-  /* eslint-disable no-magic-numbers */
-
-  // a container for all time elements
-  var timeElements = {
-    y: 0,
-    d: 0,
-    t: [],
-    h: 0,
-    m: 0,
-    s: 0
-  };
-
-  // the initial divisor
-  var divisor = TIME_SCALES[0].divisor;
-
-  // break up the input
-  var split = TIME_LABEL_PATTERN.exec(label);
-
-  // take the broken apart pieces and consume them
-  _.each(_.slice(split, 1), function (value, index) {
-    var pieces;
-
-    // skip undefined values
-    if (value === undefined) {
-      return;
-    }
-
-    // get the numeric and unit components, if any
-    pieces = /^:?(\d*)([yd])?/.exec(value);
-
-    switch (index) {
-    case 0:
-    case 1:
-      // year and day are just keys
-      timeElements[pieces[2]] = +pieces[1];
-      break;
-    case 2:
-    case 3:
-    case 4:
-      // time is only slightly trickier; missing elements get pushed down
-      timeElements.t.push(+pieces[1]);
-      break;
-    }
-  });
-
-  while (timeElements.t.length < 3) {
-    // complete the time picture with leading zeros
-    timeElements.t.unshift(0);
-  }
-
-  // convert time parts to keys
-  timeElements.h = timeElements.t[0];
-  timeElements.m = timeElements.t[1];
-  timeElements.s = timeElements.t[2];
-
-  // now we can discard the time array
-  delete timeElements.t;
-
-  // now, reduce the time elements by the scaling factors
-  return _.reduce(TIME_SCALES, function (prev, timeScale, index) {
-    // the divisor grows with each time scale factor
-    divisor *= timeScale.divisor;
-
-    // if the time element is represented, multiply by current divisor
-    if (timeElements[timeScale.units]) {
-      // if there are more time scales to go, make sure the current value
-      // does not exceed its limits (ex: 90s should be 1:30 instead)
-      if (index < TIME_SCALES.length - 1) {
-        if (timeElements[timeScale.units] >= TIME_SCALES[index + 1].divisor) {
-          throw new Error("Enter a valid time value");
-        }
-      }
-
-      // continue to accumulate the time
-      prev += timeElements[timeScale.units] * divisor;
-    }
-
-    return prev;
-  }, 0);
-
-  /* eslint-enable no-magic-numbers */
-};
-
 /**
  * Given a moment in time, the start time, and time units, produce the
  * correct time index.
@@ -305,18 +134,15 @@ MetricsProvider.prototype.setZoomLevel = function setZoomLevel(zoom) {
  * An object containing the time range is returned
  */
 MetricsProvider.prototype.getAvailableTimeRange = function getAvailableTimeRange() {
+  var maxAverages = this._aggregation[this.lowestAggregateTimeUnits].data.length - 1;
   return {
     minTime: {
-      label: getTimeIndexLabel(0, this.lowestAggregateTimeUnits),
+      label: time.getLabel(0),
       value: 0
     },
     maxTime: {
-      label: getTimeIndexLabel(
-        this._aggregation[this.lowestAggregateTimeUnits].data.length - 1,
-        this.lowestAggregateTimeUnits
-      ),
-      value: (this._aggregation[this.lowestAggregateTimeUnits].data.length - 1)
-        * this.lowestAggregateTimeUnits
+      label: time.getLabel(maxAverages * this.lowestAggregateTimeUnits),
+      value: maxAverages * this.lowestAggregateTimeUnits
     }
   };
 };
@@ -759,7 +585,7 @@ MetricsProvider.prototype.getXAxis =
       timeIndex >= -scrollOffset;
       timeIndex--
     ) {
-      xAxis.push(getTimeIndexLabel(timeIndex, +this.zoomLevelKey));
+      xAxis.push(time.getLabel(timeIndex * +this.zoomLevelKey));
     }
 
     return xAxis;
@@ -793,7 +619,7 @@ MetricsProvider.prototype.validateTimeLabel =
     }
 
     // must be able to convert (this can throw too)
-    timeValue = convertTimeLabelToMilliseconds(label);
+    timeValue = time.convertTimeLabelToMilliseconds(label);
 
     // must be a number in range
     if (isNaN(timeValue) || !_.inRange(timeValue, 0, timeRange.maxTime.value + 1)) {