[embeddable] centralize should fetch embeddable observable logic (#15…

…1799)

Fixes #151223 and
#151128

PR does the following
1) creates `shouldFetch$` method that centralizes logic for checking
when an embeddable should fetch.
2) updates Lens and Maps embeddable to use `shouldFetch$`
3) Adds unit tests for Maps embeddable to capture behavior of unique
edge cases

---------

Co-authored-by: kibanamachine <[email protected]>

src/plugins/dashboard/public/dashboard_container/embeddable/integrations/diff_state/dashboard_diffing_functions.ts

@@ -15,6 +15,7 @@ import {
   isFilterPinned,
   onlyDisabledFiltersChanged,
 } from '@kbn/es-query';
+import { shouldRefreshFilterCompareOptions } from '@kbn/embeddable-plugin/public';
 
 import { DashboardContainer } from '../../dashboard_container';
 import { DashboardContainerByValueInput } from '../../../../../common';
@@ -117,12 +118,6 @@ export const unsavedChangesDiffingFunctions: DashboardDiffFunctions = {
   viewMode: () => false, // When compared view mode is always considered unequal so that it gets backed up.
 };
 
-const shouldRefreshFilterCompareOptions = {
-  ...COMPARE_ALL_OPTIONS,
-  // do not compare $state to avoid refreshing when filter is pinned/unpinned (which does not impact results)
-  state: false,
-};
-
 export const shouldRefreshDiffingFunctions: DashboardDiffFunctions = {
   ...unsavedChangesDiffingFunctions,
   filters: ({ currentValue, lastValue }) =>

src/plugins/embeddable/public/index.ts

@@ -87,6 +87,8 @@ export {
   EmbeddableRenderer,
   useEmbeddableFactory,
   isFilterableEmbeddable,
+  shouldFetch$,
+  shouldRefreshFilterCompareOptions,
 } from './lib';
 
 export { AttributeService, ATTRIBUTE_SERVICE_KEY } from './lib/attribute_service';

src/plugins/embeddable/public/lib/filterable_embeddable/index.ts

@@ -8,3 +8,4 @@
 
 export type { FilterableEmbeddable } from './types';
 export { isFilterableEmbeddable } from './types';
+export { shouldFetch$, shouldRefreshFilterCompareOptions } from './should_fetch';

src/plugins/embeddable/public/lib/filterable_embeddable/should_fetch.tsx

@@ -0,0 +1,44 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+import fastIsEqual from 'fast-deep-equal';
+import { Observable } from 'rxjs';
+import { map, distinctUntilChanged, skip, startWith } from 'rxjs/operators';
+import { COMPARE_ALL_OPTIONS, onlyDisabledFiltersChanged } from '@kbn/es-query';
+import type { FilterableEmbeddableInput } from './types';
+
+export const shouldRefreshFilterCompareOptions = {
+  ...COMPARE_ALL_OPTIONS,
+  // do not compare $state to avoid refreshing when filter is pinned/unpinned (which does not impact results)
+  state: false,
+};
+
+export function shouldFetch$<
+  TFilterableEmbeddableInput extends FilterableEmbeddableInput = FilterableEmbeddableInput
+>(
+  updated$: Observable<unknown>,
+  getInput: () => TFilterableEmbeddableInput
+): Observable<TFilterableEmbeddableInput> {
+  return updated$.pipe(map(() => getInput())).pipe(
+    // wrapping distinctUntilChanged with startWith and skip to prime distinctUntilChanged with an initial input value.
+    startWith(getInput()),
+    distinctUntilChanged((a: TFilterableEmbeddableInput, b: TFilterableEmbeddableInput) => {
+      if (
+        !fastIsEqual(
+          [a.searchSessionId, a.query, a.timeRange, a.timeslice],
+          [b.searchSessionId, b.query, b.timeRange, b.timeslice]
+        )
+      ) {
+        return false;
+      }
+
+      return onlyDisabledFiltersChanged(a.filters, b.filters, shouldRefreshFilterCompareOptions);
+    }),
+    skip(1)
+  );
+}

src/plugins/embeddable/public/lib/filterable_embeddable/types.ts

@@ -6,7 +6,15 @@
  * Side Public License, v 1.
  */
 
-import { type AggregateQuery, type Filter, type Query } from '@kbn/es-query';
+import type { AggregateQuery, Filter, Query, TimeRange } from '@kbn/es-query';
+import { EmbeddableInput } from '../embeddables';
+
+export type FilterableEmbeddableInput = EmbeddableInput & {
+  filters?: Filter[];
+  query?: Query;
+  timeRange?: TimeRange;
+  timeslice?: [number, number];
+};
 
 /**
  * All embeddables that implement this interface should support being filtered

x-pack/plugins/lens/public/embeddable/embeddable.tsx

@@ -55,6 +55,7 @@ import {
   cellValueTrigger,
   CELL_VALUE_TRIGGER,
   type CellValueContext,
+  shouldFetch$,
 } from '@kbn/embeddable-plugin/public';
 import type { Action, UiActionsStart } from '@kbn/ui-actions-plugin/public';
 import type { DataViewsContract, DataView } from '@kbn/data-views-plugin/public';
@@ -501,20 +502,11 @@ export class Embeddable
 
     // Update search context and reload on changes related to search
     this.inputReloadSubscriptions.push(
-      this.getUpdated$()
-        .pipe(map(() => this.getInput()))
-        .pipe(
-          distinctUntilChanged((a, b) =>
-            fastIsEqual(
-              [a.filters, a.query, a.timeRange, a.searchSessionId],
-              [b.filters, b.query, b.timeRange, b.searchSessionId]
-            )
-          ),
-          skip(1)
-        )
-        .subscribe(async (input) => {
+      shouldFetch$<LensEmbeddableInput>(this.getUpdated$(), () => this.getInput()).subscribe(
+        (input) => {
           this.onContainerStateChanged(input);
-        })
+        }
+      )
     );
   }