RE: [ws-caf] Mt Everest and WS-CF

["Furniss, Peter" <Peter.Furniss@choreology.com>]

Greg,

<snip the earlier part of the alastair .. thread>

> A further comment on the IBM/MS product specs: there are in 
> fact three 
> contextualization mechanisms: one in WS-Coordination, one in 
> WS-ReliableMessaging, and one in WS-Addressing. Putting aside 
> WS-Addressing for a moment since it introduces a new model to the web 
> services environment that I don't want to argue about here, let me 
> observe that there is no fundamental distinction between the 
> lifecycle 
> control interface in WS-Coordination and WS-ReliableMessaging. Why 
> shouldn't these be based on a common model? Wouldn't that in fact be 
> simpler and less error prone? From there, it seems a small step to 
> imagine the reliability and coordination/transaction contexts 
> having a 
> common root. I submit that this is in fact a flaw, not a strength, of 
> the specification set; they they are unnecessarily complex due to the 
> failure to deal with common constructs, idioms and patterns as, well, 
> things-in-common.
> 

Well the WS-Coordination and WS-RM both have equivalent of "begin".
WS-RM doesn't always use it, 
and when it is used, it is asked of the eventual receiver. The
termination sequences are different, since WS-RM is just stopping, and
WS-Coordination will have delegated to a transaction protocol. 

As contextualization, it is true that a message carrying the relevant
headers is "in the context" of those headers, and subject to their
implications. But the same is true of more or less any header - that's
what they're for. WS-Addressing is particularly interesting because it
is essentially "opaque context" - the reference properties don't need to
contain any kind of identifier in the ws-context sense at all (it might
tell the receiver which database to look in, but since only the receiver
knows what they meant, that's fine - it's just a piece of syntactic
partitioning of the address). The other two would have an identifier but
that's the only thing they share, I think.

Peter