derivative metric aggregation

src/ui/public/agg_types/controls/sub_agg.html

@@ -0,0 +1,28 @@
+<div ng-controller="aggParam.controller">
+  <div class="form-group">
+    <label>Metric</label>
+    <select
+      name="buckets_path"
+      ng-model="agg.params.buckets_path"
+      required
+      class="form-control">
+      <option
+        ng-repeat="respAgg in responseValueAggs track by respAgg.id"
+        value="{{respAgg.id}}"
+        ng-if="respAgg.type.name !== 'derivative'"
+        ng-disabled="rejectAgg(respAgg)"
+        ng-selected="agg.params.buckets_path === respAgg.id">
+        metric: {{safeMakeLabel(respAgg)}}
+      </option>
+      <option value="custom" ng-selected="agg.params.buckets_path === 'custom'">
+        Custom Metric
+      </option>
+    </select>
+  </div>
+  <ng-form name="customMetricForm" ng-if="agg.params.buckets_path === 'custom'" class="vis-editor-agg-order-agg">
+    <vis-editor-agg-params
+      agg="agg.params.customMetric"
+      group-name="'metrics'">
+    </vis-editor-agg-params>
+  </ng-form>
+</div>

src/ui/public/agg_types/index.js

@@ -11,6 +11,7 @@ import AggTypesMetricsStdDeviationProvider from 'ui/agg_types/metrics/std_deviat
 import AggTypesMetricsCardinalityProvider from 'ui/agg_types/metrics/cardinality';
 import AggTypesMetricsPercentilesProvider from 'ui/agg_types/metrics/percentiles';
 import AggTypesMetricsPercentileRanksProvider from 'ui/agg_types/metrics/percentile_ranks';
+import AggTypesMetricsDerivativeProvider from 'ui/agg_types/metrics/derivative';
 import AggTypesBucketsDateHistogramProvider from 'ui/agg_types/buckets/date_histogram';
 import AggTypesBucketsHistogramProvider from 'ui/agg_types/buckets/histogram';
 import AggTypesBucketsRangeProvider from 'ui/agg_types/buckets/range';
@@ -34,7 +35,8 @@ export default function AggTypeService(Private) {
       Private(AggTypesMetricsCardinalityProvider),
       Private(AggTypesMetricsPercentilesProvider),
       Private(AggTypesMetricsPercentileRanksProvider),
-      Private(AggTypesMetricsTopHitProvider)
+      Private(AggTypesMetricsTopHitProvider),
+      Private(AggTypesMetricsDerivativeProvider),
     ],
     buckets: [
       Private(AggTypesBucketsDateHistogramProvider),

src/ui/public/agg_types/metrics/derivative.js

@@ -0,0 +1,142 @@
+import AggTypesMetricsMetricAggTypeProvider from 'ui/agg_types/metrics/metric_agg_type';
+import orderAggTemplate from 'ui/agg_types/controls/sub_agg.html';
+import _ from 'lodash';
+import $ from 'jquery';
+import VisAggConfigProvider from 'ui/vis/agg_config';
+import VisSchemasProvider from 'ui/vis/schemas';
+
+export default function AggTypeMetricDerivativeProvider(Private) {
+  const DerivativeAggType = Private(AggTypesMetricsMetricAggTypeProvider);
+  const AggConfig = Private(VisAggConfigProvider);
+  const Schemas = Private(VisSchemasProvider);
+
+  const aggFilter = ['!top_hits', '!percentiles', '!median', '!std_dev'];
+  const orderAggSchema = (new Schemas([
+    {
+      group: 'none',
+      name: 'orderAgg',
+      title: 'Order Agg',
+      aggFilter: aggFilter
+    }
+  ])).all[0];
+
+  return new DerivativeAggType({
+    name: 'derivative',
+    title: 'Derivative',
+    makeLabel: function (aggConfig) {
+      if (aggConfig.params.customMetric) {
+        let label = aggConfig.params.customMetric.makeLabel();
+        if (label.includes('Derivative of ')) {
+          label = '2. derivative of ' + label.substring('Derivative of '.length);
+        }
+        else if (label.includes('derivative of ')) {
+          label = (parseInt(label.substring(0, 1)) + 1) + label.substring(1);
+        }
+        else {
+          label = 'Derivative of ' + label;
+        }
+        return label;
+      }
+      const metric = aggConfig.vis.aggs.find(agg => agg.id === aggConfig.params.buckets_path);
+      return 'Derivative of ' + metric.makeLabel();
+    },
+    params: [
+      {
+        name: 'customMetric',
+        type: AggConfig,
+        default: null,
+        serialize: function (customMetric) {
+          return customMetric.toJSON();
+        },
+        deserialize: function (state, agg) {
+          return this.makeAgg(agg, state);
+        },
+        makeAgg: function (termsAgg, state) {
+          state = state || {};
+          state.schema = orderAggSchema;
+          const orderAgg = new AggConfig(termsAgg.vis, state);
+          orderAgg.id = termsAgg.id + '-orderAgg';
+          return orderAgg;
+        },
+        write: _.noop
+      },
+      {
+        name: 'buckets_path',
+        editor: orderAggTemplate,
+        controller: function ($scope, $element) {
+
+          $scope.safeMakeLabel = function (agg) {
+            try {
+              return agg.makeLabel();
+            } catch (e) {
+              return '- agg not valid -';
+            }
+          };
+
+          $scope.$watch('responseValueAggs', updateOrderAgg);
+          $scope.$watch('agg.params.buckets_path', updateOrderAgg);
+
+          $scope.$on('$destroy', function () {
+            if ($scope.aggForm && $scope.aggForm.agg) {
+              $scope.aggForm.agg.$setValidity('bucket', true);
+            }
+          });
+
+          // Returns true if the agg is not compatible with the terms bucket
+          $scope.rejectAgg = function (agg) {
+            // aggFilter elements all starts with a '!'
+            // so the index of agg.type.name in a filter is 1 if it is included
+            return Boolean(aggFilter.find((filter) => filter.indexOf(agg.type.name) === 1));
+          };
+
+          function checkBuckets() {
+            const buckets = $scope.vis.aggs.filter(agg => agg.schema.group === 'buckets');
+            const bucketIsHistogram = ['date_histogram', 'histogram'].includes(buckets[0].type.name);
+            const canUseDerivative = buckets.length === 1 && bucketIsHistogram;
+            if ($scope.aggForm.agg) $scope.aggForm.agg.$setValidity('bucket', canUseDerivative);
+            if (canUseDerivative) {
+              if (buckets[0].type.name === 'histogram') {
+                buckets[0].params.min_doc_count = 1;
+              }
+              else {
+                buckets[0].params.min_doc_count = 0;
+              }
+            }
+          }
+
+          function updateOrderAgg() {
+            const agg = $scope.agg;
+            const params = agg.params;
+            const bucketsPath = params.buckets_path;
+            const paramDef = agg.type.params.byName.customMetric;
+
+            checkBuckets();
+
+            // we aren't creating a custom aggConfig
+            if (bucketsPath !== 'custom') {
+              params.customMetric = null;
+              return;
+            }
+
+            params.customMetric = params.customMetric || paramDef.makeAgg(agg);
+          }
+        },
+        write: function (agg, output) {
+          const vis = agg.vis;
+          const orderAgg = agg.params.customMetric || vis.aggs.getResponseAggById(agg.params.buckets_path);
+
+          if (agg.params.customMetric && agg.params.customMetric.type.name !== 'count') {
+            output.parentAggs = (output.parentAggs || []).concat(orderAgg);
+          }
+
+          output.params = {};
+          if (orderAgg.type.name === 'count') {
+            output.params.buckets_path = '_count';
+          } else {
+            output.params.buckets_path = orderAgg.id;
+          }
+        }
+      }
+    ]
+  });
+}