SQL Server Transport Upgrade Version 9 to 10

Message-driven publish/subscribe deprecation

Customers who are currently using message-driven publish/subscribe compatibility should migrate to native publish/subscribe instead. Compatibility functionality is marked as obsolete with a warning for this version and will be treated as an error starting in the next major release.

Migration Steps

Assuming a transport configuration setup similar to:

async Task Initialize()
{
    var endpointConfiguration = new EndpointConfiguration("MyEndpoint");

    // Rest of your transport configuration here
    var transport = new SqlServerTransport("connectionString");
    // ...

    // Enable message-driven publish/subscribe compatibility
    transport.EnableMessageDrivenPubSubCompatibilityMode();

    var routing = endpointConfiguration.UseTransport(transport);
    routing.RegisterPublisher(
        assembly: typeof(MyEvent).Assembly,
        publisherEndpoint: "Publisher");
}

The following steps need to be taken for all event types that require migration:

• Disable auto-subscribe for each event type
• Unsubscribe from each event type using the endpoint instance unsubscribe API
• Remove usage of both RegisterPublisher and EnableMessageDrivenPubSubCompatibilityMode.

An example of how this may be done is as follows:

async Task Initialize(bool migrateAwayFromMessageDrivenPubSub = false)
{
    if (migrateAwayFromMessageDrivenPubSub)
    {
        await MigrateAwayFromMessageDrivenPubSub();
    }

    var endpointConfiguration = new EndpointConfiguration("MyEndpoint");

    // Rest of your transport configuration here
    var transport = new SqlServerTransport("connectionString");
    // ...

    var routingConfig = config.UseTransport(transport);
}

async Task MigrateAwayFromMessageDrivenPubSub()
{
    var endpointConfiguration = new EndpointConfiguration("MyEndpoint");

    // Disable auto-subscribe only for events that need to be migrated
    var autoSubscribe = config.AutoSubscribe();
    autoSubscribe.DisableFor<MyEvent>();

    // Rest of your transport configuration here
    var transport = new SqlServerTransport("connectionString");
    // ...

    // Enable message-driven publish/subscribe compatibility
    transport.EnableMessageDrivenPubSubCompatibilityMode();

    var routing = endpointConfiguration.UseTransport(transport);
    routing.RegisterPublisher(
        assembly: typeof(MyEvent).Assembly,
        publisherEndpoint: "Publisher");

    var endpointInstance = await Endpoint.Start(endpointConfiguration);

    // Unsubscribe only for events that need to be migrated
    await endpointInstance.Unsubscribe<MyEvent>();

    await endpointInstance.Stop();
}

Queue peek batch size deprecation

The queue peek batch size configuration (SqlServerTransport.QueuePeeker.MaxRecordsToPeek, and the peekBatchSize parameter of the legacy QueuePeekerOptions(delay, peekBatchSize) overload) has no effect and is deprecated. It has had no effect since Version 6.2: the number of messages received per peek is bounded by the configured message processing concurrency, and the receive loop stops as soon as the queue is drained.

Configuring it produces a compile-time warning and logs a runtime warning starting in the next Version 9 minor release. In Version 10, using it produces a compilation error. Remove it from the transport configuration.