Re: [ws-tx] Issue 007 - WS-C: Make Register/RegisterResponse retriable

[Kevin Conner <Kevin.Conner@jboss.com>]

Mark Little wrote:
> crash failures: wsa:MessageID won't work unless we mandate that 
> implementations persist their message structures, which isn't a good 
> idea IMO. Adding a unique participant identification to the registration 
> message, as Peter suggests in a different issue, would solve this, but 
> there are other solutions too. The advantage of Peter's option is that 
> it may be needed to resolve another issue.

In either scenario we need to persist something.

> In general, all of our messages are going to have to cope with transient 
> failures. So I'd prefer to use wsa:MessageID across the board for that.

+1 of course the definition of a transient failure changes with the MEP 
in use.

> For crash failures, at least in this case, I'd like to suggest we take a 
> look at what we did in WS-CAF with the WS-Coordination Framework 
> specification. There's a recoverParticipant operation that essentially 
> lets you replace one registered EPR with another EPR and returns the 
> protocol-specific EPR that you'd get from register. I think if we're 
> going to tolerate crash failures, and by that I mean try to prevent them 
> from aborting/cancelling inflight transactions unnecessarily, we need 
> such a mechanism in general. Of course that could be the scope of a 
> different issue, but I'd rather not solve the crash failure case here in 
> an ad hoc manner if we agree that it's something we need to solve more 
> generally.

At least with having a second register message we could differentiate 
between the regegistration of a crashed participant or a clash in 
identifier generation.

	Kev