From 960fee4050fd9ac6b4bd63e158e4c7f847864807 Mon Sep 17 00:00:00 2001
From: Nika Hassani <nikaws@amazon.com>
Date: Wed, 2 Aug 2023 14:56:35 -0700
Subject: [PATCH] fix(datastore): make event history list thread safe

---
 .../amplify/amplify_datastore/DataStoreHubEventStreamHandler.kt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/amplify_datastore/android/src/main/kotlin/com/amazonaws/amplify/amplify_datastore/DataStoreHubEventStreamHandler.kt b/packages/amplify_datastore/android/src/main/kotlin/com/amazonaws/amplify/amplify_datastore/DataStoreHubEventStreamHandler.kt
index 77417417c9..c04ef90a90 100644
--- a/packages/amplify_datastore/android/src/main/kotlin/com/amazonaws/amplify/amplify_datastore/DataStoreHubEventStreamHandler.kt
+++ b/packages/amplify_datastore/android/src/main/kotlin/com/amazonaws/amplify/amplify_datastore/DataStoreHubEventStreamHandler.kt
@@ -38,7 +38,7 @@ class DataStoreHubEventStreamHandler : EventChannel.StreamHandler {
     private var forwardHubResponse: (event: Map<String, Any>) -> Unit
 
     // DataStore hub event history. Used to track events which may be lost on hot restart, such as sync and ready events.
-    private var eventHistory: MutableList<HubEvent<*>> = mutableListOf()
+    private var eventHistory: MutableList<HubEvent<*>> = java.util.Collections.synchronizedList(mutableListOf())
 
     // Event types which should be replayed on hot restart.
     private val replayEvents: Set<String> = setOf(