[Question] How do you handle NotFound, Conflict, and Forbidden when editing resources?

[ChristopherHaws]

I'm curious how you would handle some common, real world scenarios using command handlers:

• The resource cannot be found (i.e. If the course could not be found here)
• The resource has a concurrency token and they don't match when trying to update (which should turn into a 409 Conflict HTTP status code)
• The user trying to edit a specific resource does not have permission to do so using resource based auth. It seems like the Controller/PageModel should be in charge of handling auth, but then you would have to lookup the resource in the Controller/PageModel to run auth on it and look it up again in the command handler.

[jbogard]

Typically I still handle all of this at the controller level. If there is something at the handler level that can return that response, I use that instead, and decorate the response with the additional information.