Missing imports after upgrading from 0.6.3 to 1.0.1

[alexandrenetbr]

I migrated my project from version 0.6.7 to 1.0.1, and I noticed that several import paths are no longer available. Specifically, I couldn't find the following packages or classes:

import org.eclipse.milo.opcua.sdk.client.api.subscriptions...
import org.eclipse.milo.opcua.sdk.client.api.UaSession
import org.eclipse.milo.opcua.sdk.client.api.config...
import org.eclipse.milo.opcua.stack.client.DiscoveryClient

Could you please clarify:

Have these packages been removed or relocated in version 1.0.1?
What are the new equivalents or recommended alternatives for these classes?
Is there a migration guide or changelog that details these structural changes?

Thanks in advance for your help!

[kevinherron]

I'm sorry but there is no migration guide or anything like that. There were significant changes to the client subscription API for 1.0. The best place to look right now is at the current examples:

• https://github.com/eclipse-milo/milo/blob/1.0/milo-examples/client-examples/src/main/java/org/eclipse/milo/examples/client/SubscriptionDataExample.java
• https://github.com/eclipse-milo/milo/blob/1.0/milo-examples/client-examples/src/main/java/org/eclipse/milo/examples/client/SubscriptionEventExample.java

In 0.6.x there was kind of two separate Subscription APIs - OpcUaSubscriptionManager, OpcUaSubscription, OpcUaMonitoredItem were a little lower level, and the "Managed" API, ManagedSubscription, etc... were a little higher level. Neither were particularly good or easy to use. This PR introducing the new Subscription API talks about it a little bit.

It will not be as simple as updating imports.

[alexandrenetbr]

Hi Kevin, I've encountered issues with the following code that used to work in previous versions:

 client.getSubscriptionManager().addSubscriptionListener(new UaSubscriptionManager.SubscriptionListener() {

            @Override
            public void onPublishFailure(UaException exception) {
                log.error(String.format("onPublishFailure exception: %s",
                        exception.toString()));
            }

            @Override
            public void onNotificationDataLost(UaSubscription subscription) {
                log.error(String.format("onNotificationDataLost event for %s",
                        subscription.toString()));
            }

            @Override
            public void onSubscriptionTransferFailed(UaSubscription subscription,
                    StatusCode statusCode) {
                log.error(String.format("onSubscriptionTransferFailed event for %s, status = %s",
                        subscription.toString(),
                        statusCode.toString()));
                Stack.sharedExecutor().execute(() -> {
                    List<Tag> tags = deviceOperation.getTagsForSubscriptionId(subscription.getSubscriptionId());
                    if (tags != null && !tags.isEmpty()) {
                        deviceOperation.createSubscription(tags);
                    }
                });
            }
        });

In version 1.0.1, getSubscriptionManager no longer exists. What is the recommended way to migrate this listener logic?

Thanks in advance for your help!

[kevinherron]

Look at the OpcUaSubscription.SubscriptionListener interface: https://github.com/eclipse-milo/milo/blob/1.0/opc-ua-sdk/sdk-client/src/main/java/org/eclipse/milo/opcua/sdk/client/subscriptions/OpcUaSubscription.java#L1587

Add a listener to each Subscription you create.

[alexandrenetbr]

Hi! I'm now using version 1.0.1 of the Milo SDK, and I noticed that the example code does not seem to match the current API for the OpcUaSubscription class.

Specifically:

The constructor new OpcUaSubscription(client) used in the example does not exist in version 1.0.1. The actual constructor requires multiple parameters:

public OpcUaSubscription(
OpcUaClient client,
UInteger subscriptionId,
double revisedPublishingInterval,
UInteger revisedLifetimeCount,
UInteger revisedMaxKeepAliveCount,
UInteger maxNotificationsPerPublish,
boolean publishingEnabled,
UByte priority)

Additionally, the method call subscription.create() also does not exist in the current implementation of OpcUaSubscription.

It looks like the example might be outdated. Could you please clarify which version the example targets, or if there's a newer recommended way to handle subscriptions and monitored items with the current public API?

Thanks for the great work on Milo!

[kevinherron]

It does exist. I think you may be looking at 0.6.x code still.

milo/opc-ua-sdk/sdk-client/src/main/java/org/eclipse/milo/opcua/sdk/client/subscriptions/OpcUaSubscription.java

Lines 96 to 100 in 530229b

	public OpcUaSubscription(OpcUaClient client) {
	this.client = client;
	deliveryQueue = new TaskQueue(client.getTransport().getConfig().getExecutor());
	}

[kevinherron]

Do note that the Maven dependency coordinates have changed.

A dependency on the client SDK would look like:

    <dependency>
      <groupId>org.eclipse.milo</groupId>
      <artifactId>milo-sdk-client</artifactId>
      <version>1.0.1</version>
    </dependency>

[alexandrenetbr]

Thanks for the clarification — it turned out to be a caching issue on IntelliJ's side. After clearing all caches, the correct methods and constructors showed up.

I’ll now continue migrating my code to be fully compatible with version 1.0.1.