I'm developing an OPC UA server based on open62541.
One of the nodes is publishing a json string every minute.
Using the OPC Quick Client I can set a subscription and see it getting updated every minute. Server, address, value, quality and timestamp all seem ok.
Also when using UaExpert I can see it getting updated every minute.
Problems start to arise when I try open Ignition Designer, add a tag for the OPC UA node and add a script on valueChanged. The script only gets called when I apply it in the script editor but it doesn't get called every minute, as I would expect.
When I check the wrapper.log, I see NullPointerException: Error processing tag value change every minute (same as the update rate). You can find the full stack trace below.
I assume that some configuration in open62541 is incompatible with Ignition but since I can't debug Ignition, I have no idea where to start looking.
What is the best way to troubleshoot this? Does this sound familiar to anybody?
INFO | jvm 1 | 2021/10/12 14:43:50 | E [t.e.core ] [12:43:50]: Error processing tag value change.
INFO | jvm 1 | 2021/10/12 14:43:50 | java.lang.NullPointerException: null
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.common.TypeUtilities.coerce(TypeUtilities.java:1365)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.common.TypeUtilities.coerceNullSafe(TypeUtilities.java:838)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.tags.runtime.nodes.ExecutableTag.coerceAndCheck(ExecutableTag.java:312)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.tags.runtime.nodes.ExecutableTag.valueChanged(ExecutableTag.java:379)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.tags.actors.factories.value.AbstractValueGeneratingActor.fireValueChange(AbstractValueGeneratingActor.java:73)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.tags.actors.factories.value.AbstractValueGeneratingActor.fireValueChange(AbstractValueGeneratingActor.java:45)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.tags.actors.factories.value.opc.OpcActorFactory$OpcActor.setValue(OpcActorFactory.java:818)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.opcua.client.connection.OpcUaSubscriptionSynchronizer$DataValueConsumer.accept(OpcUaSubscriptionSynchronizer.kt:625)
INFO | jvm 1 | 2021/10/12 14:43:50 | at com.inductiveautomation.ignition.gateway.opcua.client.connection.OpcUaSubscriptionSynchronizer$DataValueConsumer.accept(OpcUaSubscriptionSynchronizer.kt:597)
INFO | jvm 1 | 2021/10/12 14:43:50 | at org.eclipse.milo.opcua.sdk.client.subscriptions.OpcUaMonitoredItem.lambda$setValueConsumer$0(OpcUaMonitoredItem.java:152)
INFO | jvm 1 | 2021/10/12 14:43:50 | at org.eclipse.milo.opcua.sdk.client.subscriptions.OpcUaMonitoredItem.onValueArrived(OpcUaMonitoredItem.java:212)
INFO | jvm 1 | 2021/10/12 14:43:50 | at org.eclipse.milo.opcua.sdk.client.subscriptions.OpcUaSubscriptionManager.lambda$null$44(OpcUaSubscriptionManager.java:695)
INFO | jvm 1 | 2021/10/12 14:43:50 | at org.eclipse.milo.opcua.stack.core.util.ExecutionQueue$Task.run(ExecutionQueue.java:119)
INFO | jvm 1 | 2021/10/12 14:43:50 | at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
INFO | jvm 1 | 2021/10/12 14:43:50 | at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
INFO | jvm 1 | 2021/10/12 14:43:50 | at java.base/java.lang.Thread.run(Unknown Source)
INFO | jvm 1 | 2021/10/12 14:44:11 | E [d.T.TCPConnection[4840] ] [12:44:11]: Connection lost.
INFO | jvm 1 | 2021/10/12 14:44:11 | java.io.IOException: End of stream reached.
INFO | jvm 1 | 2021/10/12 14:44:11 | at com.inductiveautomation.iosession.socket.AsyncSocketIOSession.run(AsyncSocketIOSession.java:74)
INFO | jvm 1 | 2021/10/12 14:44:11 | at java.base/java.lang.Thread.run(Unknown Source)