Comments on: Request/Response Service Layer: Processing Requests

By: Davy Brion

Davy Brion — Wed, 11 Nov 2009 22:11:53 +0000

@Udi

ah, that definitely looks interesting

By: Udi Dahan

Udi Dahan — Wed, 11 Nov 2009 19:09:06 +0000

We've now integrated a WCF facade into NServiceBus as described here. In short, you write a one-liner class and NServiceBus exposes the relevant message over WCF.

By: Davy Brion

Davy Brion — Tue, 10 Nov 2009 14:35:01 +0000

@Craig

it would definitely be a useful addition to the series if you keep supplying the upcoming posts with other alternative decisions/approaches that you guys used

By: Craig Wilson

Craig Wilson — Tue, 10 Nov 2009 14:15:38 +0000

Davy,
Thanks for the article. We adopted this strategy a little over a year ago and it has been great. One difference is that we don’t guarantee a response for every request. Instead, if an exception occurs with an earlier request, we simply abort immediately and the client gets a fault exception. We have a few known types of faults that the dispatcher handles gracefully and other ones that are considered Exceptional.

By: Davy Brion

Davy Brion — Tue, 10 Nov 2009 13:24:02 +0000

yeah, the logging is ugly and could be moved to another place… but as long as i don’t see an immediate practical benefit to doing so, i don’t see the point in changing it

doing it asynchronously isn’t really necessary because it really doesn’t take up any time

By: Awkward Coder

Awkward Coder — Tue, 10 Nov 2009 11:41:17 +0000

Seems a bit of SRP method violation in ‘Process’ – it’s executing the handler as well as evaluating the performance, wouldn’t it be better to do the performance analysis asynchronously from an audit log(database table).

And if you push the stopwatch into some kind of disposable Audit class you can remove the try\finally…

Also if you push the response successful evaluation into the Response object then you can remove a few more lines of code

I do like it

By: Davy Brion

Davy Brion — Tue, 10 Nov 2009 06:59:02 +0000

@Udi

you asked me the same thing when i first posted about this over a year ago and my answer at the time was:

“I’ve only seen introductions to it, and while i like it, it’s not always an easy sell to customers… WCF (unfortunately) is”

Since then, we have recently started using NServiceBus to communicate between 2 different applications but we don’t use it for communication between the client-side and the server-side within the same application/system. For one, it’s not possible to send messages through NServiceBus from a Silverlight client and that is something that we simply have to be able to do since most of our front-ends are in Silverlight these days.

By: Aaron Fischer

Aaron Fischer — Mon, 09 Nov 2009 20:36:08 +0000

@Udi I would think this is very similar to an MVC framework rather then a bus?

By: Udi Dahan

Udi Dahan — Mon, 09 Nov 2009 20:25:57 +0000

Have you had a chance to look at NServiceBus? It's an open source framework that does a lot of things you're describing.