feat: add bucket selector aggregation (#184)

Author: adrianboratyn

.eslintrc

@@ -22,7 +22,8 @@
           "precision_threshold",
           "missing_order",
           "missing_bucket",
-          "bucket_script"
+          "bucket_script",
+          "bucket_selector"
         ]
       }
     ]

src/lib/aggregations/get-bucket-selector.ts

@@ -0,0 +1,15 @@
+export type BucketSelectorAggregation = {
+    bucket_selector: BucketSelectorAggregationBody
+}
+
+export type BucketSelectorAggregationBody = {
+    buckets_path: Record<string, string>
+    script: string
+}
+
+export const getBucketSelectorAggregation = (script: string, bucketsPath: Record<string, string>): BucketSelectorAggregation => ({
+    bucket_selector: {
+        buckets_path: bucketsPath,
+        script
+    }
+})

src/lib/aggregations/index.ts

@@ -17,3 +17,4 @@ export * from './get-stats-bucket'
 export * from './get-nested'
 export * from './get-filter'
 export * from './get-bucket-script'
+export * from './get-bucket-selector'

src/lib/aggregations/test/get-bucket-script.spec.ts

@@ -63,6 +63,8 @@ describe('getBucketScriptAggregation', () => {
                     value: expect.any(Number)
                 })
             )
+
+            expect(bucket.script.value).toEqual(bucket.sum.value / bucket.count.value)
         })
     })
 

src/lib/aggregations/test/get-bucket-selector.spec.ts

@@ -0,0 +1,107 @@
+import { ResponseError } from 'lib/common'
+import { HomeDocument } from 'test/module'
+import { TEST_ELASTICSEARCH_NODE } from 'test/constants'
+import { setupNestApplication } from 'test/toolkit'
+import { ElasticsearchModule } from 'module/elasticsearch.module'
+import { ElasticsearchService } from 'module/elasticsearch.service'
+import { getTermsAggregation } from '../get-terms'
+import { getSumAggregation } from '../get-sum'
+import { getBucketSelectorAggregation } from '../get-bucket-selector'
+
+describe('getBucketSelectorAggregation', () => {
+    const { app } = setupNestApplication({
+        imports: [
+            ElasticsearchModule.register({
+                node: TEST_ELASTICSEARCH_NODE
+            })
+        ]
+    })
+
+    it('accepts object with string values for each field', () => {
+        const query = getBucketSelectorAggregation('params.myVar1 > 5', {
+            myVar1: 'theSum'
+        })
+
+        expect(query).toEqual({
+            bucket_selector: {
+                buckets_path: {
+                    myVar1: 'theSum'
+                },
+                script: 'params.myVar1 > 5'
+            }
+        })
+    })
+
+    it('should query elasticsearch for bucket selector aggregation', async () => {
+        const service = app.get(ElasticsearchService)
+
+        const selectorFilterValue = 5
+
+        const result = await service.search(HomeDocument, {
+            size: 0,
+            aggregations: {
+                date: {
+                    ...getTermsAggregation('contractDate'),
+                    aggregations: {
+                        sum: getSumAggregation('builtInYear'),
+                        selector: getBucketSelectorAggregation(`params.myVar1 > ${selectorFilterValue}`, {
+                            myVar1: 'sum'
+                        })
+                    }
+                }
+            }
+        })
+
+        expect(result.aggregations.date.buckets.length).toBeGreaterThan(0)
+
+        result.aggregations.date.buckets.forEach(bucket => {
+            expect(bucket.sum).toEqual(
+                expect.objectContaining({
+                    value: expect.any(Number)
+                })
+            )
+
+            expect(bucket.sum.value).toBeGreaterThan(selectorFilterValue)
+        })
+    })
+
+    it('should return an error if bucket selector aggregation is not inside another aggregation', async () => {
+        const service = app.get(ElasticsearchService)
+
+        await service
+            .search(HomeDocument, {
+                size: 0,
+                aggregations: {
+                    sum: getSumAggregation('builtInYear'),
+                    selector: getBucketSelectorAggregation('params.myVar1 > 5', {
+                        myVar1: 'sum'
+                    })
+                }
+            })
+            .catch(error => {
+                expect(error).toBeInstanceOf(ResponseError)
+                expect(error.message).toContain('action_request_validation_exception')
+                expect(error.message).toContain('bucket_selector aggregation [selector] must be declared inside of another aggregation')
+            })
+    })
+
+    it(`should return an error if bucket selector tries to use non existing aggregation path`, async () => {
+        const service = app.get(ElasticsearchService)
+
+        await service
+            .search(HomeDocument, {
+                size: 0,
+                aggregations: {
+                    sum: getSumAggregation('builtInYear'),
+                    selector: getBucketSelectorAggregation('params.myVar1 > 5', {
+                        myVar1: 'sumAggregation'
+                    })
+                }
+            })
+            .catch(error => {
+                expect(error).toBeInstanceOf(ResponseError)
+                expect(error.message).toContain('action_request_validation_exception')
+                expect(error.message).toContain('No aggregation found for path [sumAggregation]')
+            })
+    })
+})

src/lib/aggregations/test/get-filter.spec.ts

@@ -7,7 +7,7 @@ import { ElasticsearchModule } from 'module/elasticsearch.module'
 import { getFilterAggregation } from '../get-filter'
 import { getSumAggregation } from '../get-sum'
 
-describe('getTermsAggregation', () => {
+describe('getFilterAggregation', () => {
     const { app } = setupNestApplication({
         imports: [
             ElasticsearchModule.register({

src/lib/aggregations/test/get-terms.spec.ts

@@ -1,11 +1,11 @@
 import { MissingOrder, Order } from 'lib/enums'
+import { ResponseError } from 'lib/common'
 import { TEST_ELASTICSEARCH_NODE } from 'test/constants'
 import { setupNestApplication } from 'test/toolkit'
 import { HomeDocument } from 'test/module'
 import { ElasticsearchService } from 'module/elasticsearch.service'
 import { ElasticsearchModule } from 'module/elasticsearch.module'
 import { getTermsAggregation } from '../get-terms'
-import { ResponseError } from 'lib/common'
 import { getNestedAggregation } from '../get-nested'
 
 describe('getTermsAggregation', () => {

src/lib/aggregations/types.ts

@@ -17,6 +17,7 @@ import { StatsBucketAggregation } from './get-stats-bucket'
 import { NestedAggregation } from './get-nested'
 import { FilterAggregation } from './get-filter'
 import { BucketScriptAggregation } from './get-bucket-script'
+import { BucketSelectorAggregation } from './get-bucket-selector'
 
 export type AggregationList<TDocument extends Document> =
     | AvgAggregation<TDocument>
@@ -38,6 +39,7 @@ export type AggregationList<TDocument extends Document> =
     | NestedAggregation<TDocument>
     | FilterAggregation<TDocument>
     | BucketScriptAggregation
+    | BucketSelectorAggregation
 
 export type AggregationsContainer<TDocument extends Document> = Record<string, Aggregations<TDocument>>