OPC UA Node error

Module Development
1

Hi,

We have a Module that has been running on our projects for few years but we have noticed that since we updated ignition to 8.1 we receive this error.

Caused by: java.lang.ClassNotFoundException: org.eclipse.milo.opcua.sdk.server.api.nodes.Node

Has something changed to kick up this error?

2

Yes. It may be as simple as recompiling your module with v8.1 dependencies. See this discussion:

3 Likes
4

With the SDK change, is that this part of the code?

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <ignition-sdk-version>8.1.0</ignition-sdk-version>
</properties>
5

Presumably. I don’t use maven, so my build environment is totally different.

6

I’ve updated the SDK to 8.1.0 but i’m still getting the same error.

java.lang.NoClassDefFoundError: org/eclipse/milo/opcua/sdk/server/api/nodes/Node

at com.hanleyenergy.drivers.modbus.configuration.ModbusTcpDriverType.createDriver(ModbusTcpDriverType.java:61)

at com.inductiveautomation.ignition.gateway.opcua.server.DriverAdapter.startup(DriverAdapter.kt:128)

at com.inductiveautomation.ignition.gateway.opcua.server.DeviceManager$DeviceAddressSpace.startup(DeviceManager.kt:331)

at com.inductiveautomation.ignition.gateway.opcua.server.DeviceManager.createAndStartupDevice(DeviceManager.kt:194)

at com.inductiveautomation.ignition.gateway.opcua.server.DeviceManager.access$createAndStartupDevice(DeviceManager.kt:43)

at com.inductiveautomation.ignition.gateway.opcua.server.DeviceManager$DeviceSettingsRecordListener$recordUpdated$1.invokeSuspend(DeviceManager.kt:286)
7

Did you recompile your module? Something isn’t right here because you still have code that references a package that no longer exists.

8

I recompiled and resigned it after i made the changes

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <ignition-sdk-version>8.1.0</ignition-sdk-version>
</properties>

This is the correct piece to change ?

9

It’s a great candidate, but I couldn’t tell you anything definitively without seeing your entire project.

You may also simply have old dependencies being added inside your module that gets built as a result of not cleaning first (mvn clean).

10

This lead me to the real issue.
The AccessLevel class has been changed with the recent milo update.
They changed the ‘getMask’ function