yaml tests passing using a personl instance of ES, working on specifying the host/port

scripts/generate/logs/samples/weighted_list.js

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+/**
+ * @class WeightedList
+ * @constructor
+ */
+
+module.exports = WeightedList;
+
+var _ = require('../../../../src/lib/utils');
+
+function WeightedList(list) {
+  WeightedList.callSuper(this, arguments);
+  _.forEach(list, _.bindKey(this, 'push'));
+}
+_.inherits(WeightedList, Array);
+
+/**
+ * Add a value to the weighted list.
+ * @method add
+ * @param {Any} value
+ * @param {Number} [weight] Optional.  Defaults to 1.
+ * @return {Number} The index of the item that was added.
+ */
+WeightedList.prototype.push = function (weight, value) {
+  if (!weight && weight !== 0) {
+    weight = 1;
+  }
+
+  Array.prototype.push.call(this, {
+    value: value,
+    weight: weight
+  });
+
+  delete this._sum;
+  delete this._totals;
+
+  return this.length - 1;
+};
+
+WeightedList.prototype.get = function () {
+  return this[this._randomIndex()].value;
+};
+
+/**
+ * Returns an index by weighted random distribution.
+ * @method _randomIndex
+ * @protected
+ * @return {Number}
+ */
+WeightedList.prototype._randomIndex = function () {
+  var maximumIndex,
+    me = this,
+    middleIndex,
+    minimumIndex = 0,
+    random,
+    sum = me._sum,
+    total,
+    totals = me._totals;
+
+  if (!sum || !totals) {
+    me._update();
+
+    sum = me._sum;
+    totals = me._totals;
+
+    if (!sum || !totals || !totals.length) {
+      return null;
+    }
+  }
+
+  maximumIndex = totals.length - 1;
+  random = Math.random() * sum;
+
+  while (maximumIndex >= minimumIndex) {
+    middleIndex = (maximumIndex + minimumIndex) / 2;
+
+    if (middleIndex < 0) {
+      middleIndex = 0;
+    } else {
+      middleIndex = Math.floor(middleIndex);
+    }
+
+    total = totals[middleIndex];
+
+    if (random === total) {
+      middleIndex += 1;
+      break;
+    } else if (random < total) {
+      if (middleIndex && random > totals[middleIndex - 1]) {
+        break;
+      }
+
+      maximumIndex = middleIndex - 1;
+    } else if (random > total) {
+      minimumIndex = middleIndex + 1;
+    }
+  }
+
+  return middleIndex;
+};
+
+/**
+ * Updates chached data for achieving weighted random distribution.
+ * @method _update
+ * @chainable
+ * @protected
+ */
+WeightedList.prototype._update = function () {
+  var me = this,
+    sum = 0,
+    totals = [];
+
+  _.each(me, function (item) {
+    sum += item.weight;
+    totals.push(sum);
+  });
+
+  me._sum = sum;
+  me._totals = totals;
+
+  return me;
+};