[Sessions] Add meta.size to bfetched responses

docs/development/plugins/data/public/kibana-plugin-plugins-data-public.ikibanasearchresponse.md

@@ -7,7 +7,7 @@
 <b>Signature:</b>
 
 ```typescript
-export interface IKibanaSearchResponse<RawResponse = any> 
+export interface IKibanaSearchResponse<RawResponse = any> extends BatchResultBase 
 ```
 
 ## Properties

examples/bfetch_explorer/public/plugin.tsx

@@ -8,6 +8,7 @@
 
 import { Plugin, CoreSetup, AppNavLinkStatus } from '../../../src/core/public';
 import { BfetchPublicSetup, BfetchPublicStart } from '../../../src/plugins/bfetch/public';
+import { BatchResultBase } from '../../../src/plugins/bfetch/common';
 import { mount } from './mount';
 import { DeveloperExamplesSetup } from '../../developer_examples/public';
 
@@ -24,12 +25,16 @@ export interface BfetchExplorerStartPlugins {
   bfetch: BfetchPublicStart;
 }
 
+interface ExampleResponse extends BatchResultBase {
+  num: number;
+}
+
 export class BfetchExplorerPlugin implements Plugin {
   public setup(
     core: CoreSetup<BfetchExplorerStartPlugins, void>,
     { bfetch, developerExamples }: BfetchExplorerSetupPlugins
   ) {
-    const double = bfetch.batchedFunction<{ num: number }, { num: number }>({
+    const double = bfetch.batchedFunction<{ num: number }, ExampleResponse>({
       url: '/bfetch_explorer/double',
     });
 

src/plugins/bfetch/common/batch.ts

@@ -10,11 +10,20 @@ export interface ErrorLike {
   message: string;
 }
 
+export interface BatchResultBase {
+  meta?: {
+    size: number;
+  };
+}
+
 export interface BatchRequestData<Item> {
   batch: Item[];
 }
 
-export interface BatchResponseItem<Result extends object, Error extends ErrorLike = ErrorLike> {
+export interface BatchResponseItem<
+  Result extends BatchResultBase,
+  Error extends ErrorLike = ErrorLike
+> {
   id: number;
   result?: Result;
   error?: Error;

src/plugins/bfetch/public/batching/create_streaming_batched_function.test.ts

@@ -310,8 +310,8 @@ describe('createStreamingBatchedFunction()', () => {
       expect(await isPending(promise1)).toBe(true);
       expect(await isPending(promise2)).toBe(false);
       expect(await isPending(promise3)).toBe(false);
-      expect(await promise2).toEqual({ foo: 'bar' });
-      expect(await promise3).toEqual({ foo: 'bar 2' });
+      expect(await promise2).toEqual({ foo: 'bar', meta: { size: 31 } });
+      expect(await promise3).toEqual({ foo: 'bar 2', meta: { size: 33 } });
     });
 
     test('resolves falsy results', async () => {
@@ -429,9 +429,9 @@ describe('createStreamingBatchedFunction()', () => {
       const [, error2] = await promise2;
       const [result3] = await promise3;
 
-      expect(result1).toEqual({ b: '1' });
+      expect(result1).toEqual({ b: '1', meta: { size: 27 } });
       expect(error2).toEqual({ b: '2' });
-      expect(result3).toEqual({ b: '3' });
+      expect(result3).toEqual({ b: '3', meta: { size: 27 } });
     });
 
     describe('when requests are aborted', () => {
@@ -497,7 +497,7 @@ describe('createStreamingBatchedFunction()', () => {
         await new Promise((r) => setTimeout(r, 1));
 
         const [result2] = await of(promise2);
-        expect(result2).toEqual({ b: '2' });
+        expect(result2).toEqual({ b: '2', meta: { size: 27 } });
       });
     });
 

src/plugins/bfetch/public/batching/create_streaming_batched_function.ts

@@ -13,6 +13,7 @@ import {
   createBatchedFunction,
   BatchResponseItem,
   ErrorLike,
+  BatchResultBase,
 } from '../../common';
 import { fetchStreaming, split } from '../streaming';
 import { normalizeError } from '../../common';
@@ -22,7 +23,7 @@ export interface BatchedFunctionProtocolError extends ErrorLike {
   code: string;
 }
 
-export interface StreamingBatchedFunctionParams<Payload, Result> {
+export interface StreamingBatchedFunctionParams<Payload, Result extends BatchResultBase> {
   /**
    * URL endpoint that will receive a batch of requests. This endpoint is expected
    * to receive batch as a serialized JSON array. It should stream responses back
@@ -56,7 +57,7 @@ export interface StreamingBatchedFunctionParams<Payload, Result> {
  * server using `params.fetchStreaming` in a POST request. Responses are streamed back
  * and each batch item is resolved once corresponding response is received.
  */
-export const createStreamingBatchedFunction = <Payload, Result extends object>(
+export const createStreamingBatchedFunction = <Payload, Result extends BatchResultBase>(
   params: StreamingBatchedFunctionParams<Payload, Result>
 ): BatchedFunc<Payload, Result> => {
   const {
@@ -134,6 +135,11 @@ export const createStreamingBatchedFunction = <Payload, Result extends object>(
               if (response.error) {
                 items[response.id].future.reject(response.error);
               } else if (response.result !== undefined) {
+                if (typeof response.result === 'object') {
+                  response.result.meta = {
+                    size: json.length,
+                  };
+                }
                 items[response.id].future.resolve(response.result);
               }
             } catch (e) {

src/plugins/bfetch/public/plugin.ts

@@ -8,7 +8,7 @@
 
 import { CoreStart, PluginInitializerContext, CoreSetup, Plugin } from 'src/core/public';
 import { fetchStreaming as fetchStreamingStatic, FetchStreamingParams } from './streaming';
-import { removeLeadingSlash } from '../common';
+import { removeLeadingSlash, BatchResultBase } from '../common';
 import {
   createStreamingBatchedFunction,
   StreamingBatchedFunctionParams,
@@ -23,7 +23,7 @@ export interface BfetchPublicStartDependencies {}
 
 export interface BfetchPublicContract {
   fetchStreaming: (params: FetchStreamingParams) => ReturnType<typeof fetchStreamingStatic>;
-  batchedFunction: <Payload, Result extends object>(
+  batchedFunction: <Payload, Result extends BatchResultBase>(
     params: StreamingBatchedFunctionParams<Payload, Result>
   ) => BatchedFunc<Payload, Result>;
 }

src/plugins/data/common/search/types.ts

@@ -9,6 +9,7 @@
 import { Observable } from 'rxjs';
 import { IEsSearchRequest, IEsSearchResponse } from './es_search';
 import { IndexPattern } from '..';
+import { BatchResultBase } from '../../../bfetch/common';
 
 export type ISearchGeneric = <
   SearchStrategyRequest extends IKibanaSearchRequest = IEsSearchRequest,
@@ -37,7 +38,7 @@ export interface ISearchClient {
   extend: ISearchExtendGeneric;
 }
 
-export interface IKibanaSearchResponse<RawResponse = any> {
+export interface IKibanaSearchResponse<RawResponse = any> extends BatchResultBase {
   /**
    * Some responses may contain a unique id to identify the request this response came from.
    */

src/plugins/data/public/public.api.md

@@ -1262,10 +1262,11 @@ export interface IKibanaSearchRequest<Params = any> {
     params?: Params;
 }
 
+// Warning: (ae-forgotten-export) The symbol "BatchResultBase" needs to be exported by the entry point index.d.ts
 // Warning: (ae-missing-release-tag) "IKibanaSearchResponse" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
 // @public (undocumented)
-export interface IKibanaSearchResponse<RawResponse = any> {
+export interface IKibanaSearchResponse<RawResponse = any> extends BatchResultBase {
     id?: string;
     isPartial?: boolean;
     isRunning?: boolean;

test/examples/bfetch_explorer/batched_function.ts

@@ -38,18 +38,27 @@ export default function ({ getService }: FtrProviderContext) {
         {
           num: 300,
           result: {
+            meta: {
+              size: 29,
+            },
             num: 600,
           },
         },
         {
           num: 1000,
           result: {
+            meta: {
+              size: 30,
+            },
             num: 2000,
           },
         },
         {
           num: 2000,
           result: {
+            meta: {
+              size: 30,
+            },
             num: 4000,
           },
         },