[Partial Results] Update esaggs expressions function to return partial results

docs/development/plugins/expressions/public/kibana-plugin-plugins-expressions-public.iexpressionloaderparams.md

@@ -22,11 +22,12 @@ export interface IExpressionLoaderParams
 |  [hasCompatibleActions](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.hascompatibleactions.md) | <code>ExpressionRenderHandlerParams['hasCompatibleActions']</code> |  |
 |  [inspectorAdapters](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.inspectoradapters.md) | <code>Adapters</code> |  |
 |  [onRenderError](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.onrendererror.md) | <code>RenderErrorHandlerFnType</code> |  |
-|  [partial](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.partial.md) | <code>boolean</code> |  |
+|  [partial](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.partial.md) | <code>boolean</code> | The flag to toggle on emitting partial results. By default, the partial results are disabled. |
 |  [renderMode](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.rendermode.md) | <code>RenderMode</code> |  |
 |  [searchContext](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.searchcontext.md) | <code>SerializableState</code> |  |
 |  [searchSessionId](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.searchsessionid.md) | <code>string</code> |  |
 |  [syncColors](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.synccolors.md) | <code>boolean</code> |  |
+|  [throttle](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.throttle.md) | <code>number</code> | Throttling of partial results in milliseconds. By default, throttling is disabled. |
 |  [uiState](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.uistate.md) | <code>unknown</code> |  |
 |  [variables](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.variables.md) | <code>Record&lt;string, any&gt;</code> |  |
 

docs/development/plugins/expressions/public/kibana-plugin-plugins-expressions-public.iexpressionloaderparams.partial.md

@@ -4,6 +4,8 @@
 
 ## IExpressionLoaderParams.partial property
 
+The flag to toggle on emitting partial results. By default, the partial results are disabled.
+
 <b>Signature:</b>
 
 ```typescript

docs/development/plugins/expressions/public/kibana-plugin-plugins-expressions-public.iexpressionloaderparams.throttle.md

@@ -0,0 +1,13 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [kibana-plugin-plugins-expressions-public](./kibana-plugin-plugins-expressions-public.md) &gt; [IExpressionLoaderParams](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.md) &gt; [throttle](./kibana-plugin-plugins-expressions-public.iexpressionloaderparams.throttle.md)
+
+## IExpressionLoaderParams.throttle property
+
+Throttling of partial results in milliseconds. By default, throttling is disabled.
+
+<b>Signature:</b>
+
+```typescript
+throttle?: number;
+```

src/plugins/data/common/search/expressions/esaggs/esaggs_fn.ts

@@ -7,6 +7,7 @@
  */
 
 import { i18n } from '@kbn/i18n';
+import { Observable } from 'rxjs';
 
 import { Datatable, ExpressionFunctionDefinition } from 'src/plugins/expressions/common';
 
@@ -22,7 +23,7 @@ import { handleRequest } from './request_handler';
 const name = 'esaggs';
 
 type Input = KibanaContext | null;
-type Output = Promise<Datatable>;
+type Output = Observable<Datatable>;
 
 interface Arguments {
   index: IndexPatternExpressionType;

src/plugins/data/common/search/expressions/esaggs/request_handler.test.ts

@@ -6,6 +6,7 @@
  * Side Public License, v 1.
  */
 
+import { from } from 'rxjs';
 import type { MockedKeys } from '@kbn/utility-types/jest';
 import type { Filter } from '../../../es_query';
 import type { IndexPattern } from '../../../index_patterns';
@@ -21,6 +22,7 @@ jest.mock('../../tabify', () => ({
 
 import { tabifyAggResponse } from '../../tabify';
 import { of } from 'rxjs';
+import { toArray } from 'rxjs/operators';
 
 describe('esaggs expression function - public', () => {
   let mockParams: MockedKeys<RequestHandlerParams>;
@@ -57,15 +59,15 @@ describe('esaggs expression function - public', () => {
   });
 
   test('should create a new search source instance', async () => {
-    await handleRequest(mockParams);
+    await handleRequest(mockParams).toPromise();
     expect(mockParams.searchSourceService.create).toHaveBeenCalledTimes(1);
   });
 
   describe('sets the expected fields on search source', () => {
     let searchSource: MockedKeys<ISearchSource>;
 
     beforeEach(async () => {
-      await handleRequest(mockParams);
+      await handleRequest(mockParams).toPromise();
       searchSource = await mockParams.searchSourceService.create();
     });
 
@@ -100,7 +102,7 @@ describe('esaggs expression function - public', () => {
       await handleRequest({
         ...mockParams,
         filters: mockFilters,
-      });
+      }).toPromise();
       searchSource = await mockParams.searchSourceService.create();
       expect((searchSource.setField as jest.Mock).mock.calls[3]).toEqual(['filter', mockFilters]);
     });
@@ -118,14 +120,14 @@ describe('esaggs expression function - public', () => {
       await handleRequest({
         ...mockParams,
         query: mockQuery,
-      });
+      }).toPromise();
       searchSource = await mockParams.searchSourceService.create();
       expect((searchSource.setField as jest.Mock).mock.calls[4]).toEqual(['query', mockQuery]);
     });
   });
 
   test('calls searchSource.fetch', async () => {
-    await handleRequest(mockParams);
+    await handleRequest(mockParams).toPromise();
     const searchSource = await mockParams.searchSourceService.create();
 
     expect(searchSource.fetch$).toHaveBeenCalledWith({
@@ -140,7 +142,7 @@ describe('esaggs expression function - public', () => {
   });
 
   test('tabifies response data', async () => {
-    await handleRequest(mockParams);
+    await handleRequest(mockParams).toPromise();
     expect(tabifyAggResponse).toHaveBeenCalledWith(
       mockParams.aggs,
       {},
@@ -155,7 +157,7 @@ describe('esaggs expression function - public', () => {
     await handleRequest({
       ...mockParams,
       timeRange: { from: '2020-12-01', to: '2020-12-31' },
-    });
+    }).toPromise();
     expect((tabifyAggResponse as jest.Mock).mock.calls[0][2].timeRange).toMatchInlineSnapshot(`
       Object {
         "from": "2020-12-01T05:00:00.000Z",
@@ -167,4 +169,29 @@ describe('esaggs expression function - public', () => {
       }
     `);
   });
+
+  test('returns partial results', async () => {
+    const searchSource = await mockParams.searchSourceService.create();
+
+    (searchSource.fetch$ as jest.MockedFunction<typeof searchSource.fetch$>).mockReturnValue(
+      from([
+        {
+          rawResponse: {},
+        },
+        {
+          rawResponse: {},
+        },
+      ]) as ReturnType<typeof searchSource.fetch$>
+    );
+
+    const result = await handleRequest({
+      ...mockParams,
+      query: { query: 'foo', language: 'bar' },
+    })
+      .pipe(toArray())
+      .toPromise();
+
+    expect(result).toHaveLength(2);
+    expect(tabifyAggResponse).toHaveBeenCalledTimes(2);
+  });
 });

src/plugins/data/common/search/expressions/esaggs/request_handler.ts

@@ -7,6 +7,8 @@
  */
 
 import { i18n } from '@kbn/i18n';
+import { defer } from 'rxjs';
+import { map, switchMap } from 'rxjs/operators';
 import { Adapters } from 'src/plugins/inspector/common';
 
 import { calculateBounds, Filter, IndexPattern, Query, TimeRange } from '../../../../common';
@@ -32,7 +34,7 @@ export interface RequestHandlerParams {
   getNow?: () => Date;
 }
 
-export const handleRequest = async ({
+export const handleRequest = ({
   abortSignal,
   aggs,
   filters,
@@ -46,87 +48,95 @@ export const handleRequest = async ({
   timeRange,
   getNow,
 }: RequestHandlerParams) => {
-  const forceNow = getNow?.();
-  const searchSource = await searchSourceService.create();
-
-  searchSource.setField('index', indexPattern);
-  searchSource.setField('size', 0);
-
-  // Create a new search source that inherits the original search source
-  // but has the appropriate timeRange applied via a filter.
-  // This is a temporary solution until we properly pass down all required
-  // information for the request to the request handler (https://github.com/elastic/kibana/issues/16641).
-  // Using callParentStartHandlers: true we make sure, that the parent searchSource
-  // onSearchRequestStart will be called properly even though we use an inherited
-  // search source.
-  const timeFilterSearchSource = searchSource.createChild({ callParentStartHandlers: true });
-  const requestSearchSource = timeFilterSearchSource.createChild({ callParentStartHandlers: true });
-
-  // If timeFields have been specified, use the specified ones, otherwise use primary time field of index
-  // pattern if it's available.
-  const defaultTimeField = indexPattern?.getTimeField?.();
-  const defaultTimeFields = defaultTimeField ? [defaultTimeField.name] : [];
-  const allTimeFields = timeFields && timeFields.length > 0 ? timeFields : defaultTimeFields;
-
-  aggs.setTimeRange(timeRange as TimeRange);
-  aggs.setForceNow(forceNow);
-  aggs.setTimeFields(allTimeFields);
-
-  // For now we need to mirror the history of the passed search source, since
-  // the request inspector wouldn't work otherwise.
-  Object.defineProperty(requestSearchSource, 'history', {
-    get() {
-      return searchSource.history;
-    },
-    set(history) {
-      return (searchSource.history = history);
-    },
-  });
-
-  requestSearchSource.setField('aggs', aggs);
-
-  requestSearchSource.onRequestStart((paramSearchSource, options) => {
-    return aggs.onSearchRequestStart(paramSearchSource, options);
-  });
-
-  // If a timeRange has been specified and we had at least one timeField available, create range
-  // filters for that those time fields
-  if (timeRange && allTimeFields.length > 0) {
-    timeFilterSearchSource.setField('filter', () => {
-      return aggs.getSearchSourceTimeFilter(forceNow);
+  return defer(async () => {
+    const forceNow = getNow?.();
+    const searchSource = await searchSourceService.create();
+
+    searchSource.setField('index', indexPattern);
+    searchSource.setField('size', 0);
+
+    // Create a new search source that inherits the original search source
+    // but has the appropriate timeRange applied via a filter.
+    // This is a temporary solution until we properly pass down all required
+    // information for the request to the request handler (https://github.com/elastic/kibana/issues/16641).
+    // Using callParentStartHandlers: true we make sure, that the parent searchSource
+    // onSearchRequestStart will be called properly even though we use an inherited
+    // search source.
+    const timeFilterSearchSource = searchSource.createChild({ callParentStartHandlers: true });
+    const requestSearchSource = timeFilterSearchSource.createChild({
+      callParentStartHandlers: true,
     });
-  }
-
-  requestSearchSource.setField('filter', filters);
-  requestSearchSource.setField('query', query);
-
-  const { rawResponse: response } = await requestSearchSource
-    .fetch$({
-      abortSignal,
-      sessionId: searchSessionId,
-      inspector: {
-        adapter: inspectorAdapters.requests,
-        title: i18n.translate('data.functions.esaggs.inspector.dataRequest.title', {
-          defaultMessage: 'Data',
-        }),
-        description: i18n.translate('data.functions.esaggs.inspector.dataRequest.description', {
-          defaultMessage:
-            'This request queries Elasticsearch to fetch the data for the visualization.',
-        }),
+
+    // If timeFields have been specified, use the specified ones, otherwise use primary time field of index
+    // pattern if it's available.
+    const defaultTimeField = indexPattern?.getTimeField?.();
+    const defaultTimeFields = defaultTimeField ? [defaultTimeField.name] : [];
+    const allTimeFields = timeFields?.length ? timeFields : defaultTimeFields;
+
+    aggs.setTimeRange(timeRange as TimeRange);
+    aggs.setForceNow(forceNow);
+    aggs.setTimeFields(allTimeFields);
+
+    // For now we need to mirror the history of the passed search source, since
+    // the request inspector wouldn't work otherwise.
+    Object.defineProperty(requestSearchSource, 'history', {
+      get() {
+        return searchSource.history;
+      },
+      set(history) {
+        return (searchSource.history = history);
       },
-    })
-    .toPromise();
+    });
 
-  const parsedTimeRange = timeRange ? calculateBounds(timeRange, { forceNow }) : null;
-  const tabifyParams = {
-    metricsAtAllLevels: aggs.hierarchical,
-    partialRows,
-    timeRange: parsedTimeRange
-      ? { from: parsedTimeRange.min, to: parsedTimeRange.max, timeFields: allTimeFields }
-      : undefined,
-  };
+    requestSearchSource.setField('aggs', aggs);
 
-  const tabifiedResponse = tabifyAggResponse(aggs, response, tabifyParams);
+    requestSearchSource.onRequestStart((paramSearchSource, options) => {
+      return aggs.onSearchRequestStart(paramSearchSource, options);
+    });
 
-  return tabifiedResponse;
+    // If a timeRange has been specified and we had at least one timeField available, create range
+    // filters for that those time fields
+    if (timeRange && allTimeFields.length > 0) {
+      timeFilterSearchSource.setField('filter', () => {
+        return aggs.getSearchSourceTimeFilter(forceNow);
+      });
+    }
+
+    requestSearchSource.setField('filter', filters);
+    requestSearchSource.setField('query', query);
+
+    return { allTimeFields, forceNow, requestSearchSource };
+  }).pipe(
+    switchMap(({ allTimeFields, forceNow, requestSearchSource }) =>
+      requestSearchSource
+        .fetch$({
+          abortSignal,
+          sessionId: searchSessionId,
+          inspector: {
+            adapter: inspectorAdapters.requests,
+            title: i18n.translate('data.functions.esaggs.inspector.dataRequest.title', {
+              defaultMessage: 'Data',
+            }),
+            description: i18n.translate('data.functions.esaggs.inspector.dataRequest.description', {
+              defaultMessage:
+                'This request queries Elasticsearch to fetch the data for the visualization.',
+            }),
+          },
+        })
+        .pipe(
+          map(({ rawResponse: response }) => {
+            const parsedTimeRange = timeRange ? calculateBounds(timeRange, { forceNow }) : null;
+            const tabifyParams = {
+              metricsAtAllLevels: aggs.hierarchical,
+              partialRows,
+              timeRange: parsedTimeRange
+                ? { from: parsedTimeRange.min, to: parsedTimeRange.max, timeFields: allTimeFields }
+                : undefined,
+            };
+
+            return tabifyAggResponse(aggs, response, tabifyParams);
+          })
+        )
+    )
+  );
 };