User context

In a similar way to how Correlation IDs work, a user context may also flow through message handlers - i.e. if the special Headers.UserName header has been added to a handled message, the header will automatically be transferred to all outgoing messages when they're sent.

An endpoint may have Thread.CurrentPrincipal automatically set to a GenericPrincipal containing a GenericIdentity with the user name by going

Configure.With(...)
    .(...)
    .Behavior(b => b.SetCurrentPrincipalWhenUserNameHeaderIsPresent())
    .CreateBus().Start();