From 76553cf1c91fe8eae136493d5371101dcf9736aa Mon Sep 17 00:00:00 2001
From: AllanFly120 <zheallan@amazon.com>
Date: Mon, 2 Mar 2020 08:56:29 -0800
Subject: [PATCH] fix: return readable stream with async iterators properly
 (#956)

---
 .../eventstream-serde-node/src/EventStreamMarshaller.ts   | 8 ++++++--
 packages/eventstream-serde-node/src/utils.ts              | 6 +-----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/packages/eventstream-serde-node/src/EventStreamMarshaller.ts b/packages/eventstream-serde-node/src/EventStreamMarshaller.ts
index 747f843217fb..58de1b0b2d19 100644
--- a/packages/eventstream-serde-node/src/EventStreamMarshaller.ts
+++ b/packages/eventstream-serde-node/src/EventStreamMarshaller.ts
@@ -6,7 +6,7 @@ import {
   EventStreamMarshaller as IEventStreamMarshaller
 } from "@aws-sdk/types";
 import { Readable, pipeline } from "stream";
-import { ReadabletoIterable } from "./utils";
+import { readabletoIterable } from "./utils";
 import { EventMessageChunkerStream } from "./EventMessageChunkerStream";
 import { MessageUnmarshallerStream } from "./MessageUnmarshallerStream";
 import { EventDeserializerStream } from "./EventDeserializerStream";
@@ -44,7 +44,11 @@ export class EventStreamMarshaller {
     );
     //should use stream[Symbol.asyncIterable] when the api is stable
     //reference: https://nodejs.org/docs/latest-v11.x/api/stream.html#stream_readable_symbol_asynciterator
-    return ReadabletoIterable(eventDeserializerStream);
+    if (typeof eventDeserializerStream[Symbol.asyncIterator] === "function") {
+      // use the experimental feature if available.
+      return eventDeserializerStream;
+    }
+    return readabletoIterable(eventDeserializerStream);
   }
 
   serialize<T>(
diff --git a/packages/eventstream-serde-node/src/utils.ts b/packages/eventstream-serde-node/src/utils.ts
index b57be2125126..e092348eaeba 100644
--- a/packages/eventstream-serde-node/src/utils.ts
+++ b/packages/eventstream-serde-node/src/utils.ts
@@ -18,13 +18,9 @@ export function getSignatureBinary(signature: string): Uint8Array {
  * Reference: https://nodejs.org/docs/latest-v11.x/api/stream.html#stream_readable_symbol_asynciterator
  */
 
-export async function* ReadabletoIterable<T>(
+export async function* readabletoIterable<T>(
   readStream: Readable
 ): AsyncIterable<T> {
-  if (typeof readStream[Symbol.asyncIterator] === "function") {
-    // use the experimental feature if available.
-    throw readStream;
-  }
   let streamEnded = false;
   let generationEnded = false;
   const records = new Array<T>();