In self-hosted OWIN Web API, how to run code at shutdown?

I think there is a better way to get the CancellationToken:

var properties = new AppProperties(app.Properties);
CancellationToken token = properties.OnAppDisposing;

AppProperties is under namespace Microsoft.Owin.BuilderProperties, which comes from this nuget package: http://www.nuget.org/packages/Microsoft.Owin/

The description of property OnAppDisposing says:

Gets or sets the cancellation token for “host.OnAppDisposing”.

Please refer to: http://msdn.microsoft.com/en-us/library/microsoft.owin.builderproperties.appproperties%28v=vs.113%29.aspx