Re: Question on relation between roles and wsdl interfaces

Hello Steve
Thank you so very much for the quick response. It completely answers my 
question. In fact, after receiving your email, I went back and read the 
ws-cdl draft document again and realized that I apparently missed the 
explanation for operation attribute of an interaction.

Thank you very much
Best Regards

....Mine

Mine Altunay
PhD candidate
NC State University
ECE Dept.

On Sat, 2 Dec 2006, Steve Ross-Talbot wrote:

> Dear Mine,
>
> All interactions in WS-CDL define an operation name over a channel and 
> include a relationship name and the from and to roles for that interaction. 
> Optionally one may specify a set of exchanges (up to 3 normally, one for the 
> request, one for the response and one for a fault response). The operation 
> name may be used to tie back to a WSDL operation for the to role. If one 
> projects out all of the operations for a specific to role in a WS-CDL 
> description one would get an ordered set of of WSDL operations. The WS-CDL 
> defines the multi-party ordering and the end point projection provides the 
> specific role's ordering.
>
> In the definition of a role type in WS-CDL an optional interface can be 
> included. This may be a reference to a specific WSDL and this ties the role 
> to a specific service contract.
>
> Thus you always know which operation is invoked during an interaction because 
> the operation name and the to-role are defined.
>
> So I would say you are almost correct but that you missed the point about the 
> role being an abstract that has specific ordering constraints on the service 
> operations. Generally a role has a single behavior but that does not have to 
> be the case.
>
> If you want to find out further details carry on mailing this list but you 
> might want to cross post or look at the pi4soa implementation.
>
> Cheers
>
> Steve T
>
> On 1 Dec 2006, at 22:49, Mine Altunay wrote:
>
>> 
>> Dear list
>> My understanding of current ws-cdl standard was that each role can have 
>> multiple behaviors and each behavior corresponds to an operation listed 
>> within a service's wsdl. As a result, I view a role as an abtraction that 
>> is a collection of service operations. Each time a different behavior is 
>> assumed by a role, the corresponding web service operation would be 
>> invoked.
>> 
>> My confusion arises when I try to define interactions between different 
>> roles. An interaction consists of a relationship type and defines 
>> fromRoleTypes and toRoleTypes. However it does not specify which behaviors 
>> can be assumed during the specific interaction between two roles.
>> 
>> My problem exacerbates when I try to tie in a choreography document with a 
>> run time execution environment. Since I do not know which operation is 
>> invoked during an interaction, determining run-time  operation sequences 
>> between actual web service implementations is almost impossible.
>> 
>> Can anyone enlighten me on this? am I incorrect to tie in behaviors with 
>> actual web services operations
>> Thank you
>> ....Mine
>> 
>> 
>> 
>> Mine Altunay
>> NC State Univ, Computer Eng Dept
>> 
>> 
>> 
>> 
>> 
>
>

Mine Altunay
NC State Univ, Computer Eng Dept

Received on Saturday, 2 December 2006 20:39:34 UTC