From 8ff8dacab0cfca174a4cab51b501e73c95d08258 Mon Sep 17 00:00:00 2001
From: Christian Lewis <ctj.lewis@icloud.com>
Date: Sun, 25 Apr 2021 07:48:08 -0500
Subject: [PATCH] fix: add-to-group PostConfirmation Lambda should not throw

/**
 * For some reason, naively returning a value / Promise or throwing an error
 * will not work as it is specified in the Lambda docs:
 * @see https://docs.aws.amazon.com/lambda/latest/dg/nodejs-handler.html
 *
 * This causes an "Invalid JSON" error which can, so far, only be worked
 * around by resolving with deprecated non-async `callback`:
 * @see https://github.com/aws-amplify/amplify-cli/issues/2735
 * @see https://github.com/aws-amplify/amplify-cli/issues/4341
 * @see https://github.com/aws-amplify/amplify-cli/issues/7179
 */
---
 .../triggers/PostConfirmation/add-to-group.js | 23 +++++++++++--------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/packages/amplify-category-auth/provider-utils/awscloudformation/triggers/PostConfirmation/add-to-group.js b/packages/amplify-category-auth/provider-utils/awscloudformation/triggers/PostConfirmation/add-to-group.js
index c33dca12fc1..9c663c4a430 100644
--- a/packages/amplify-category-auth/provider-utils/awscloudformation/triggers/PostConfirmation/add-to-group.js
+++ b/packages/amplify-category-auth/provider-utils/awscloudformation/triggers/PostConfirmation/add-to-group.js
@@ -1,6 +1,6 @@
 /* eslint-disable-line */ const aws = require('aws-sdk');
 
-exports.handler = async (event, context) => {
+exports.handler = async (event, context, callback) => {
   const cognitoidentityserviceprovider = new aws.CognitoIdentityServiceProvider({ apiVersion: '2016-04-18' });
   const groupParams = {
     GroupName: process.env.GROUP,
@@ -19,16 +19,21 @@ exports.handler = async (event, context) => {
     await cognitoidentityserviceprovider.createGroup(groupParams).promise();
   }
 
+  /**
+   * For some reason, naively returning a value / Promise or throwing an error
+   * will not work as it is specified in the Lambda docs:
+   * @see https://docs.aws.amazon.com/lambda/latest/dg/nodejs-handler.html
+   *
+   * This causes an "Invalid JSON" error which can, so far, only be worked
+   * around by resolving with deprecated non-async `callback`:
+   * @see https://github.com/aws-amplify/amplify-cli/issues/2735
+   * @see https://github.com/aws-amplify/amplify-cli/issues/4341
+   * @see https://github.com/aws-amplify/amplify-cli/issues/7179
+   */
   try {
     await cognitoidentityserviceprovider.adminAddUserToGroup(addUserParams).promise();
-    return {
-      statusCode: 200,
-      body: JSON.stringify(event)
-    }
+    callback(null, event);
   } catch (error) {
-    return {
-      statusCode: 500,
-      body: JSON.stringify(error)
-    }
+    callback(new Error(error));
   }
 };