UserContextHeaders

User context headers

The purpose of this sample is to demonstrate how Rebus' hooks and message headers can be used to pass a user context around in a transparent fashion.

Things to take note of in this project:

• A special AmbientUserContext can be used to assign an ambient user context to the thread.
• An extension method, AutomaticallyTransferUserContext, is used to make the configuration reusable and pretty.
• The actual "magic" happens by hooking into two events: MessageSent (for attaching an ambient user context to the outgoing messages), and MessageContextEstablished (for detecting the user context header in the message being handled, making it available in the message context)
• A pretty extension method on IMessageContext called GetUserContext can be used to extract the current user context.
• Castle Windsor is configured to be able to inject the current user context.

Apart from the while(true) { ... } thing going on in Program, all of this code is very realistic, and I've had good results doing this kind of thing.