Endpoint API changes in NServiceBus Version 6

Endpoint name is mandatory

In NServiceBus versions 6 and above, endpoint name is mandatory.

// For NServiceBus version 6.x
var endpointConfiguration = new EndpointConfiguration("MyEndpointName");

// For NServiceBus version 5.x
var busConfiguration = new BusConfiguration();
busConfiguration.EndpointName("MyEndpointName");

The endpoint name is used as a logical identifier when sending or receiving messages. It is also used for determining the name of the input queue the endpoint will be bound to. See Derived endpoint name for the algorithm used in NServiceBus versions 5 and below to select endpoint name if backwards compatibility is a concern.

Interface changes

The IWantToRunWhenBusStartsAndStops interface is now obsolete.

If the extensibility provided by IWantToRunWhenBusStartsAndStops is still required, it can be achieved via other means in the NServiceBus endpoint lifecycle.

Self-hosting

When self-hosting, call any startup code after Endpoint.Start and cleanup code after Endpoint.Stop.

// For NServiceBus version 6.x
var endpointConfiguration = new EndpointConfiguration("EndpointName");

// Custom code before start
var endpointInstance = await Endpoint.Start(endpointConfiguration);
// Custom code after start

// Block the process

// Custom code before stop
await endpointInstance.Stop();
// Custom code after stop

// For NServiceBus version 5.x
var busConfiguration = new BusConfiguration();

// Custom code before start
var startableBus = Bus.Create(busConfiguration);
using (var bus = startableBus.Start())
{
    // Custom code after start

    // Block the process

    // Custom code before stop
}
// Custom code after stop

While the Dispose Pattern can no longer be used (since IEndpointInstance does not implement IDisposable) this is not a common use case since in most hosting scenarios, the startup code is not in the same method as the shutdown code. For example

• Windows Service Hosting where startup is usually done in ServiceBase.OnStart and shutdown is usually done in ServiceBase.OnStop.
• Web Site or Web Service Hosting where startup is usually done in HttpApplication.Application_Start and shutdown is usually done in HttpApplication.Dispose.

Using NServiceBus.Host

See the upgrade guide for more details on using the new interface provided by the host.

Endpoint name helper

An algorithm is used in NServiceBus version 5 to determine the name of the endpoint if none is provided. If the same behavior is needed in versions 6 and above, this helper class can be used.

public static class EndpointNameHelper
{
    public static string GetDefaultEndpointName()
    {
        var entryType = GetEntryType();

        if (entryType != null)
        {
            var endpointName = entryType.Namespace ?? entryType.Assembly.GetName().Name;
            if (endpointName != null)
            {
                return endpointName;
            }
        }

        throw new Exception("No endpoint name could be derived");
    }

    static Type GetEntryType()
    {
        var stackTraceToExamine = new StackTrace();
        var entryAssembly = Assembly.GetEntryAssembly();
        if (entryAssembly?.EntryPoint != null)
        {
            return entryAssembly.EntryPoint.ReflectedType;
        }

        StackFrame targetFrame = null;

        var stackFrames = new StackTrace().GetFrames();
        if (stackFrames != null)
        {
            targetFrame =
                stackFrames.FirstOrDefault(
                    f => typeof(HttpApplication).IsAssignableFrom(f.GetMethod().DeclaringType));
        }

        if (targetFrame != null)
        {
            return targetFrame.GetMethod().ReflectedType;
        }

        stackFrames = stackTraceToExamine.GetFrames();
        if (stackFrames != null)
        {
            targetFrame =
                stackFrames.FirstOrDefault(
                    f =>
                    {
                        var declaringType = f.GetMethod().DeclaringType;
                        return declaringType != typeof(EndpointConfiguration);
                    });
        }

        if (targetFrame == null)
        {
            targetFrame = stackFrames.FirstOrDefault(
                f => f.GetMethod().DeclaringType.Assembly != typeof(EndpointConfiguration).Assembly);
        }

        if (targetFrame != null)
        {
            return targetFrame.GetMethod().ReflectedType;
        }
        throw new Exception("Could not derive EndpointName");
    }

}