Backport bulk helper index drift bugfix to 7.x (#1915)

lib/Helpers.js

@@ -705,11 +705,11 @@ class Helpers {
           }
           const retry = []
           const { items } = body
+          let indexSlice = 0
           for (let i = 0, len = items.length; i < len; i++) {
             const action = items[i]
             const operation = Object.keys(action)[0]
             const { status } = action[operation]
-            const indexSlice = operation !== 'delete' ? i * 2 : i
 
             if (status >= 400) {
               // 429 is the only staus code where we might want to retry
@@ -736,6 +736,7 @@ class Helpers {
             } else {
               stats.successful += 1
             }
+            operation === 'delete' ? indexSlice += 1 : indexSlice += 2
           }
           callback(null, retry)
         })

package.json

@@ -12,7 +12,7 @@
   },
   "homepage": "http://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/index.html",
   "version": "7.17.11",
-  "versionCanary": "7.17.11-canary.0",
+  "versionCanary": "7.17.11-canary.1",
   "keywords": [
     "elasticsearch",
     "elastic",

test/unit/helpers/bulk.test.js

@@ -1082,6 +1082,70 @@ test('bulk delete', t => {
     server.stop()
   })
 
+  t.test('Should call onDrop on the correct document when doing a mix of operations that includes deletes', async t => {
+    // checks to ensure onDrop doesn't provide the wrong document when some operations are deletes
+    // see https://github.com/elastic/elasticsearch-js/issues/1751
+    async function handler (req, res) {
+      res.setHeader('content-type', 'application/json')
+      res.end(JSON.stringify({
+        took: 0,
+        errors: true,
+        items: [
+          { delete: { status: 200 } },
+          { index: { status: 429 } },
+          { index: { status: 200 } }
+        ]
+      }))
+    }
+
+    const [{ port }, server] = await buildServer(handler)
+    const client = new Client({ node: `http://localhost:${port}` })
+    let counter = 0
+    const result = await client.helpers.bulk({
+      datasource: dataset.slice(),
+      concurrency: 1,
+      wait: 10,
+      retries: 0,
+      onDocument (doc) {
+        counter++
+        if (counter === 1) {
+          return {
+            delete: {
+              _index: 'test',
+              _id: String(counter)
+            }
+          }
+        } else {
+          return {
+            index: {
+              _index: 'test'
+            }
+          }
+        }
+      },
+      onDrop (doc) {
+        t.same(doc, {
+          status: 429,
+          error: null,
+          operation: { index: { _index: 'test' } },
+          document: { user: 'arya', age: 18 },
+          retried: false
+        })
+      }
+    })
+
+    t.type(result.time, 'number')
+    t.type(result.bytes, 'number')
+    t.match(result, {
+      total: 3,
+      successful: 2,
+      retry: 0,
+      failed: 1,
+      aborted: false
+    })
+    server.stop()
+  })
+
   t.end()
 })