+ Add nested and child aggregation in visualization

src/ui/public/agg_response/tabify/tabify.js

@@ -30,10 +30,36 @@ export function AggResponseTabifyProvider(Private, Notifier) {
    */
   function collectBucket(write, bucket, key) {
     const agg = write.aggStack.shift();
+    const subAggPrefix = 'agg_';
 
     switch (agg.schema.group) {
       case 'buckets':
-        const buckets = new Buckets(bucket[agg.id]);
+        let buckets = new Buckets(bucket[agg.id]);
+
+        // traverse the agg object
+        const bucketKeys = Object.keys(bucket);
+        const bucketLength = bucketKeys.length;
+        const subAggRegex = new RegExp('(' + subAggPrefix + ')*' + agg.id, 'g');
+        let subAggCnt = 0;
+        for (let i = 0; i < bucketLength; ++i) {
+          if (bucketKeys[i].match(subAggRegex)) {
+            const subAggPrefixRegex = new RegExp(subAggPrefix, 'g');
+            // get number of sub agg
+            subAggCnt = (bucketKeys[i].match(subAggPrefixRegex) || []).length;
+            break;
+          }
+        }
+        let aggBucket = bucket;
+        while (subAggCnt > 0) {
+          const prefix = subAggPrefix.repeat(subAggCnt) + agg.id;
+          aggBucket = aggBucket[prefix];
+          subAggCnt--;
+        }
+        // get the deepest agg result
+        if (aggBucket !== undefined) {
+          buckets = new Buckets(aggBucket[agg.id]);
+        }
+
         if (buckets.length) {
           const splitting = write.canSplit && agg.schema.name === 'split';
           if (splitting) {

src/ui/public/agg_types/buckets/_bucket_agg_type.js

@@ -1,11 +1,35 @@
 import _ from 'lodash';
 import { AggTypesAggTypeProvider } from 'ui/agg_types/agg_type';
+import nestedAndChildTemplate from 'ui/agg_types/controls/nested_and_child.html';
 
 export function AggTypesBucketsBucketAggTypeProvider(Private) {
   const AggType = Private(AggTypesAggTypeProvider);
 
   _.class(BucketAggType).inherits(AggType);
   function BucketAggType(config) {
+    // always append reversed nested, child, nested
+    config.params.push(
+      {
+        name: 'reversedNested',
+        default: false,
+        write: _.noop
+      },
+      {
+        name: 'child',
+        default: [ { input: '' } ],
+        write: _.noop
+      },
+      {
+        name: 'nested',
+        default: 0,
+        write: _.noop
+      },
+      {
+        name: 'aggNestedAndChild',
+        editor: nestedAndChildTemplate
+      }
+    );
+
     BucketAggType.Super.call(this, config);
 
     if (_.isFunction(config.getKey)) {

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

@@ -0,0 +1,67 @@
+<div class="vis-option-item">
+  <label>
+    <input type="checkbox"
+    name="reversedNested"
+    ng-model="agg.params.reversedNested">
+    Reversed nested
+  </label>
+</div>
+
+<div class="form-group">
+  <div ng-repeat="child in agg.params.child">
+    <div class="vis-editor-agg-header">
+      <label>
+          Child {{$index + 1}}
+          <span ng-if="child.label">- {{ child.label }}</span>
+      </label>
+
+      <div class="kuiButtonGroup kuiButtonGroup--united">
+        <button
+          type="button"
+          ng-click="agg.params.child.splice($index, 1)"
+          class="kuiButton kuiButton--danger kuiButton--small">
+          <i class="fa fa-times"></i>
+        </button>
+      </div>
+    </div>
+
+    <div class="form-group">
+      <input
+        ng-model="child.input"
+        type="text"
+        class="form-control"
+        name="child{{$index}}">
+    </div>
+
+  </div>
+</div>
+
+<input ng-model="agg.params.child.length" name="childLength" required type="number" class="ng-hide" />
+<div class="hintbox" ng-show="aggForm.childLength.$invalid">
+  <p>
+    <i class="fa fa-danger text-danger"></i>
+    <strong>Required:</strong> You must specify at least one child.
+  </p>
+</div>
+
+<button
+  click-focus="'child'+(agg.params.child.length-1)"
+  ng-click="agg.params.child.push({input:''})"
+  class="kuiButton kuiButton--primary kuiButton--fullWidth"
+>
+  Add Child
+</button>
+
+<div class="vis-editor-agg-form-row">
+  <div class="form-group">
+    <label>Nested</label>
+    <input
+      name="nested"
+      ng-model="agg.params.nested"
+      class="form-control"
+      type="number"
+      min="0"
+    >
+  </div>
+</div>
+

src/ui/public/vis/agg_configs.js

@@ -94,6 +94,8 @@ export function VisAggConfigsProvider(Private) {
     const dslTopLvl = {};
     let dslLvlCursor;
     let nestedMetrics;
+    const subAggPrefix = 'agg_';
+    let prevSubAggCnt; // count of additional aggregation
 
     if (this.vis.isHierarchical()) {
       // collect all metrics, and filter out the ones that we won't be copying
@@ -119,19 +121,86 @@ export function VisAggConfigsProvider(Private) {
         dslLvlCursor = dslTopLvl;
       } else {
         const prevConfig = list[i - 1];
-        const prevDsl = dslLvlCursor[prevConfig.id];
+        let prevConfigKey;
+        let prevDsl;
+        if (prevSubAggCnt > 0) {
+          prevDsl = dslLvlCursor;
+          for (let i = prevSubAggCnt; i > 0; --i) {
+            prevConfigKey = subAggPrefix.repeat(i) + prevConfig.id; // previous config key: prefix * n + id
+            prevDsl = prevDsl[prevConfigKey].aggs;
+          }
+          prevDsl = prevDsl[prevConfig.id];
+        }
+        else{
+          prevDsl = dslLvlCursor[prevConfig.id];
+        }
 
         // advance the cursor and nest under the previous agg, or
         // put it on the same level if the previous agg doesn't accept
         // sub aggs
         dslLvlCursor = prevDsl.aggs || dslLvlCursor;
       }
 
-      const dsl = dslLvlCursor[config.id] = config.toDsl();
+      const dsl = config.toDsl();
       let subAggs;
 
       parseParentAggs(dslLvlCursor, dsl);
 
+      let newConfigId = config.id;
+      let newDsl = dsl; // define new dsl for additional aggregation
+      let aggObj = {}; // define aggObj to store orginal dsl
+      prevSubAggCnt = 0;
+      if (config.params.nested) {
+        const nestedArr = config.params.field.name.split('.');
+        const nestedLvl = (nestedArr.length - 1 < config.params.nested) ? nestedArr.length - 1 : config.params.nested;
+        for (let i = 0; i < nestedLvl; ++i) {
+          aggObj = {};
+          aggObj[newConfigId] = newDsl;
+          newDsl = {
+            nested: {
+              path: nestedArr[i]
+            },
+            aggs: aggObj
+          };
+          newConfigId = subAggPrefix + newConfigId;
+          prevSubAggCnt++;
+        }
+      }
+
+      if (config.params.child) {
+        const childArr = config.params.child;
+        const childCnt = childArr.length;
+        for (let i = 0; i < childCnt; ++i) {
+          const childInput = childArr[childCnt - i - 1].input;
+          if (!childInput) {
+            break;
+          }
+          aggObj = {};
+          aggObj[newConfigId] = newDsl;
+          newDsl = {
+            children: {
+              type: childInput
+            },
+            aggs: aggObj
+          };
+          newConfigId = subAggPrefix + newConfigId;
+          prevSubAggCnt++;
+        }
+      }
+
+      if (config.params.reversedNested) {
+        aggObj = {};
+        aggObj[newConfigId] = newDsl;
+        newDsl = {
+          reverse_nested: {},
+          aggs: aggObj
+        };
+        newConfigId = subAggPrefix + newConfigId;
+        prevSubAggCnt++;
+      }
+
+      dslLvlCursor[newConfigId] = newDsl;
+
       if (config.schema.group === 'buckets' && i < list.length - 1) {
         // buckets that are not the last item in the list accept sub-aggs
         subAggs = dsl.aggs || (dsl.aggs = {});