NServiceBus.Transport.AzureServiceBus 5.0.0 – Major release available

Announcements
1

Hi everyone,

We’ve just released NServiceBus.Transport.AzureServiceBus 5.0.0.

This version introduces a new topic-per-event topology that dedicates one Azure Service Bus topic to each concrete event type. This approach can dramatically reduce filtering overhead and improve both performance and scalability by distributing messages across multiple topics, each dedicated to a single event type.

For a more phased migration from the default single-topic approach in previous versions, this release also introduces a migration topology. This topology lets endpoints continue using the existing single-topic event routing approach while selectively shifting certain events to the new topic-per-event model.

This release is a major upgrade from version 4. If you’re moving from v4 (or any earlier version), careful planning is required to avoid disruptions. Please refer to the NServiceBus.Transport.AzureServiceBus version 4 to 5 upgrade guide for detailed migration steps and the topology documentation, including:

  • How to gradually migrate existing endpoints and events with the migration topology.
  • Quotas, subscription limits, and advanced considerations such as interface-based inheritance and message versioning.

We strongly recommend reading the upgrade guide in full before beginning the process.

Please share any challenges you faced or rough edges you discovered during the migration on this discussion group entry or GitHub issue. We’re actively monitoring both. If discussing specifics about your project is necessary, feel free to raise a support request. We can provide the help you need to migrate from any earlier version to the latest release.

When to upgrade

This upgrade significantly improves transport functionality. We recommend preparing early, planning the upgrade carefully, and considering the order of endpoints and events—but don’t wait until the last moment.

Where to get it

You can install NServiceBus.Transport.AzureServiceBus 5.0.0 from NuGet.

With thanks,
The team in Particular

Please read our release policy for more details.

2

With the support policy for components that says

  • Major versions are supported for a period of one year after the release of the next major version.
  • Minor versions of a supported major version are supported for a period of three months after the release of the next minor version.

Would it be possible to update the support table for the transport to clearly indicate within what timeframe the migration has to be completed? Or would the migration topology be available beyond version 5 of the ASB transport.

3

Hi

Thanks for asking. We have not yet made a final decision on when to remove the migration topology. We are going to keep it around as long, as there will be need from customers.

When considering releasing the next major we will re-assess the situation. Our goal is to make the process as smooth as possible. We hope majority of customers migrate most of their endpoints within 1 year time frame.

As part of this assessment we will consider alternative ways to maintain compatibility e.g. introducing tools and/or bridging techniques that would allow the old endpoints to talk to the new ones.