From bac828decad0d0d0fed295513c99240b59c98a3b Mon Sep 17 00:00:00 2001
From: desoliture <ikozka@thingsboard.io>
Date: Wed, 1 Dec 2021 16:16:33 +0200
Subject: [PATCH] fix null response when get timeout on rpc with zero retries

---
 .../server/actors/device/DeviceActorMessageProcessor.java     | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/application/src/main/java/org/thingsboard/server/actors/device/DeviceActorMessageProcessor.java b/application/src/main/java/org/thingsboard/server/actors/device/DeviceActorMessageProcessor.java
index 41d99a682b..f677d76ee7 100644
--- a/application/src/main/java/org/thingsboard/server/actors/device/DeviceActorMessageProcessor.java
+++ b/application/src/main/java/org/thingsboard/server/actors/device/DeviceActorMessageProcessor.java
@@ -596,6 +596,7 @@ class DeviceActorMessageProcessor extends AbstractContextAwareMsgProcessor {
         ToDeviceRpcRequestMetadata md = toDeviceRpcPendingMap.get(responseMsg.getRequestId());
 
         if (md != null) {
+            JsonNode response = null;
             if (status.equals(RpcStatus.DELIVERED)) {
                 if (md.getMsg().getMsg().isOneway()) {
                     toDeviceRpcPendingMap.remove(responseMsg.getRequestId());
@@ -611,13 +612,14 @@ class DeviceActorMessageProcessor extends AbstractContextAwareMsgProcessor {
                 if (maxRpcRetries <= md.getRetries()) {
                     toDeviceRpcPendingMap.remove(responseMsg.getRequestId());
                     status = RpcStatus.FAILED;
+                    response = JacksonUtil.newObjectNode().put("error", "There was a Timeout and all retry attempts have been exhausted. Retry attempts set: " + maxRpcRetries);
                 } else {
                     md.setRetries(md.getRetries() + 1);
                 }
             }
 
             if (md.getMsg().getMsg().isPersisted()) {
-                systemContext.getTbRpcService().save(tenantId, new RpcId(rpcId), status, null);
+                systemContext.getTbRpcService().save(tenantId, new RpcId(rpcId), status, response);
             }
             if (status != RpcStatus.SENT) {
                 sendNextPendingRequest(context);