Store the last failed zone stage sync validation as runtime ApiListener attribute

lib/remote/apilistener-filesync.cpp

@@ -385,7 +385,12 @@ void ApiListener::TryActivateZonesStageCallback(const ProcessResult& pr,
 	} else {
 		Log(LogCritical, "ApiListener")
 			<< "Config validation failed for staged cluster config sync. Aborting. Logs: '"
-			<< GetApiZonesStageDir() + "/startup.log'";
+			<< logFile << "'";
+
+		ApiListener::Ptr listener = ApiListener::GetInstance();
+
+		if (listener)
+			listener->UpdateLastFailedZonesStageValidation(pr.Output);
 	}
 }
 
@@ -416,3 +421,13 @@ void ApiListener::AsyncTryActivateZonesStage(const String& stageConfigDir, const
 	process->SetTimeout(300);
 	process->Run(std::bind(&TryActivateZonesStageCallback, _1, stageConfigDir, currentConfigDir, relativePaths, reload));
 }
+
+void ApiListener::UpdateLastFailedZonesStageValidation(const String& log)
+{
+	Dictionary::Ptr lastFailedZonesStageValidation = new Dictionary({
+		{ "log", log },
+		{ "ts", Utility::GetTime() }
+	});
+
+	SetLastFailedZonesStageValidation(lastFailedZonesStageValidation);
+}

lib/remote/apilistener.hpp

@@ -187,6 +187,8 @@ private:
 	static void AsyncTryActivateZonesStage(const String& stageConfigDir, const String& currentConfigDir,
 		const std::vector<String>& relativePaths, bool reload);
 
+	void UpdateLastFailedZonesStageValidation(const String& log);
+
 	/* configsync */
 	void UpdateConfigObject(const ConfigObject::Ptr& object, const MessageOrigin::Ptr& origin,
 		const JsonRpcConnection::Ptr& client = nullptr);

lib/remote/apilistener.ti

@@ -54,6 +54,8 @@ class ApiListener : ConfigObject
 	[state, no_user_modify] Timestamp log_message_timestamp;
 
 	[no_user_modify] String identity;
+
+	[state, no_user_modify] Dictionary::Ptr last_failed_zones_stage_validation;
 };
 
 }