[helpers] add support for transport options to all helpers (#1400)

Co-authored-by: spalger <spalger@users.noreply.github.com>

test/unit/helpers/bulk.test.js

@@ -1049,6 +1049,66 @@ test('bulk delete', t => {
   t.end()
 })
 
+test('transport options', t => {
+  t.test('Should pass transport options in request', async t => {
+    let count = 0
+    const MockConnection = connection.buildMockConnection({
+      onRequest (params) {
+        count++
+
+        if (params.path === '/_bulk') {
+          t.match(params.headers, {
+            'content-type': 'application/x-ndjson',
+            foo: 'bar'
+          })
+          return { body: { errors: false, items: [{}] } }
+        }
+
+        t.strictEqual(params.path, '/_all/_refresh')
+        t.match(params.headers, {
+          foo: 'bar'
+        })
+        return { body: {} }
+      }
+    })
+
+    const client = new Client({
+      node: 'http://localhost:9200',
+      Connection: MockConnection
+    })
+
+    const result = await client.helpers.bulk({
+      datasource: dataset.slice(),
+      flushBytes: 1,
+      concurrency: 1,
+      onDocument (doc) {
+        return { index: { _index: 'test' } }
+      },
+      onDrop (doc) {
+        t.fail('This should never be called')
+      },
+      refreshOnCompletion: true
+    }, {
+      headers: {
+        foo: 'bar'
+      }
+    })
+
+    t.strictEqual(count, 4) // three bulk requests, one refresh
+    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()
+})
+
 test('errors', t => {
   t.test('datasource type', async t => {
     const client = new Client({

test/unit/helpers/msearch.test.js

@@ -756,3 +756,42 @@ test('Stop should resolve the helper (error)', t => {
 
   m.then(() => t.fail('Should not fail'), err => t.is(err.message, 'kaboom'))
 })
+
+test('Should use req options', async t => {
+  t.plan(1)
+
+  const MockConnection = connection.buildMockConnection({
+    onRequest (params) {
+      t.match(params.headers, {
+        foo: 'bar'
+      })
+
+      return {
+        body: {
+          responses: [{
+            status: 200,
+            hits: { hits: [] }
+          }]
+        }
+      }
+    }
+  })
+
+  const client = new Client({
+    node: 'http://localhost:9200',
+    Connection: MockConnection
+  })
+
+  const m = client.helpers.msearch({ operations: 1 }, {
+    headers: {
+      foo: 'bar'
+    }
+  })
+
+  await m.search(
+    { index: 'test' },
+    { query: { match: { foo: 'bar' } } }
+  )
+
+  t.teardown(() => m.stop())
+})