[Backport 8.8] Allow document to be overwritten in onDocument iteratee of bulk helper (#1732)Co-authored-by: Josh Mock <joshua.mock@elastic.co> (#1952)

Co-authored-by: Robert Da Silva <mail@robdasilva.com>

src/helpers.ts

@@ -74,11 +74,11 @@ export interface BulkStats {
   aborted: boolean
 }
 
-interface IndexAction {
+interface IndexActionOperation {
   index: T.BulkIndexOperation
 }
 
-interface CreateAction {
+interface CreateActionOperation {
   create: T.BulkCreateOperation
 }
 
@@ -90,7 +90,9 @@ interface DeleteAction {
   delete: T.BulkDeleteOperation
 }
 
-type UpdateAction = [UpdateActionOperation, Record<string, any>]
+type CreateAction = CreateActionOperation | [CreateActionOperation, unknown]
+type IndexAction = IndexActionOperation | [IndexActionOperation, unknown]
+type UpdateAction = [UpdateActionOperation, T.BulkUpdateAction]
 type Action = IndexAction | CreateAction | UpdateAction | DeleteAction
 
 export interface OnDropDocument<TDocument = unknown> {
@@ -618,22 +620,21 @@ export default class Helpers {
       for await (const chunk of datasource) {
         if (shouldAbort) break
         timeoutRef.refresh()
-        const action = onDocument(chunk)
+        const result = onDocument(chunk)
-        const operation = Array.isArray(action)
+        const [action, payload] = Array.isArray(result) ? result : [result, chunk]
-          ? Object.keys(action[0])[0]
+        const operation = Object.keys(action)[0]
-          : Object.keys(action)[0]
         if (operation === 'index' || operation === 'create') {
           actionBody = serializer.serialize(action)
-          payloadBody = typeof chunk === 'string' ? chunk : serializer.serialize(chunk)
+          payloadBody = typeof payload === 'string'
+            ? payload
+            : serializer.serialize(payload)
           chunkBytes += Buffer.byteLength(actionBody) + Buffer.byteLength(payloadBody)
           bulkBody.push(actionBody, payloadBody)
         } else if (operation === 'update') {
-          // @ts-expect-error in case of update action is an array
+          actionBody = serializer.serialize(action)
-          actionBody = serializer.serialize(action[0])
           payloadBody = typeof chunk === 'string'
             ? `{"doc":${chunk}}`
-            // @ts-expect-error in case of update action is an array
+            : serializer.serialize({ doc: chunk, ...payload })
-            : serializer.serialize({ doc: chunk, ...action[1] })
           chunkBytes += Buffer.byteLength(actionBody) + Buffer.byteLength(payloadBody)
           bulkBody.push(actionBody, payloadBody)
         } else if (operation === 'delete') {

test/unit/helpers/bulk.test.ts

@@ -17,11 +17,11 @@
  * under the License.
  */
 
-import * as http from 'http'
+import FakeTimers from '@sinonjs/fake-timers'
 import { createReadStream } from 'fs'
+import * as http from 'http'
 import { join } from 'path'
 import split from 'split2'
-import FakeTimers from '@sinonjs/fake-timers'
 import { test } from 'tap'
 import { Client, errors } from '../../../'
 import { buildServer, connection } from '../../utils'
@@ -785,6 +785,59 @@ test('bulk index', t => {
     t.end()
   })
 
+  t.test('Should use payload returned by `onDocument`', async t => {
+    let count = 0
+    const updatedAt = '1970-01-01T12:00:00.000Z'
+    const MockConnection = connection.buildMockConnection({
+      onRequest (params) {
+        t.equal(params.path, '/_bulk')
+        t.match(params.headers, {
+          'content-type': 'application/vnd.elasticsearch+x-ndjson; compatible-with=8',
+          'x-elastic-client-meta': `es=${clientVersion},js=${nodeVersion},t=${transportVersion},hc=${nodeVersion},h=bp`
+        })
+        // @ts-expect-error
+        const [action, payload] = params.body.split('\n')
+        t.same(JSON.parse(action), { index: { _index: 'test' } })
+        t.same(JSON.parse(payload), { ...dataset[count++], updatedAt })
+        return { body: { errors: false, items: [{}] } }
+      }
+    })
+
+    const client = new Client({
+      node: 'http://localhost:9200',
+      Connection: MockConnection
+    })
+    const result = await client.helpers.bulk<Document>({
+      datasource: dataset.slice(),
+      flushBytes: 1,
+      concurrency: 1,
+      onDocument (doc) {
+        t.type(doc.user, 'string') // testing that doc is type of Document
+        return [
+          { 
+            index: { 
+              _index: 'test' 
+            } 
+          }, 
+          { ...doc, updatedAt }
+        ]
+      },
+      onDrop (doc) {
+        t.fail('This should never be called')
+      }
+    })
+
+    t.type(result.time, 'number')
+    t.type(result.bytes, 'number')
+    t.match(result, {
+      total: 3,
+      successful: 3,
+      retry: 0,
+      failed: 0,
+      aborted: false
+    })
+  })
+
   t.end()
 })
 
@@ -835,6 +888,58 @@ test('bulk create', t => {
       aborted: false
     })
   })
+
+  t.test('Should use payload returned by `onDocument`', async t => {
+    let count = 0
+    const updatedAt = '1970-01-01T12:00:00.000Z'
+    const MockConnection = connection.buildMockConnection({
+      onRequest (params) {
+        t.equal(params.path, '/_bulk')
+        t.match(params.headers, { 'content-type': 'application/vnd.elasticsearch+x-ndjson; compatible-with=8' })
+        // @ts-expect-error
+        const [action, payload] = params.body.split('\n')
+        t.same(JSON.parse(action), { create: { _index: 'test', _id: count } })
+        t.same(JSON.parse(payload), { ...dataset[count++], updatedAt })
+        return { body: { errors: false, items: [{}] } }
+      }
+    })
+
+    const client = new Client({
+      node: 'http://localhost:9200',
+      Connection: MockConnection
+    })
+    let id = 0
+    const result = await client.helpers.bulk({
+      datasource: dataset.slice(),
+      flushBytes: 1,
+      concurrency: 1,
+      onDocument (doc) {
+        return [
+          {
+            create: {
+              _index: 'test',
+              _id: String(id++)
+            }
+          }, 
+          { ...doc, updatedAt }
+        ]
+      },
+      onDrop (doc) {
+        t.fail('This should never be called')
+      }
+    })
+
+    t.type(result.time, 'number')
+    t.type(result.bytes, 'number')
+    t.match(result, {
+      total: 3,
+      successful: 3,
+      retry: 0,
+      failed: 0,
+      aborted: false
+    })
+  })
+
   t.end()
 })