[PLC4X-342] OPC UA silently fails to handle subscription response

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 0.9.1
• Component/s: Driver-OPC-UA

Language

Java

• Assignee: Ben Hutcheson
• Reporter: Łukasz Dywicki
• Created: 15/May/22 12:37
• Updated: 09/Nov/22 10:22

Description

While test of OPC UA simulator coming from freeopcua I found out that our client doesn't work with it. Maybe it is an issue of how they encode payload, maybe it is inconsistency in the spec, not sure - the end result is that actual response processing error gets swallowed and driver hangs.

Guilty code is in OpcuaSubscriptionHandle:

for (MonitoredItemCreateResult result : responseMessage.getResults().toArray(new MonitoredItemCreateResult[0])) {
    if (OpcuaStatusCode.enumForValue(result.getStatusCode().getStatusCode()) != OpcuaStatusCode.Good) {
        LOGGER.error("Invalid Field {}, subscription created without this field", fieldNames.get((int) result.getMonitoredItemId()));
    } else {
        LOGGER.debug("Field {} was added to the subscription", fieldNames.get((int) result.getMonitoredItemId() - 1)); // !monitored item id might be inconsistent!
    }
}

Copy of traffic causing issue in attachment.