Re: [ws-caf] policy ai

[Mark Little <mark.little@arjuna.com>]

Greg Pavlik wrote:

> Concerete proposals:
>
> 1) Following the convention of the WS-RX TC, I suggest we talk in 
> terms of assertions as XML fragments that define declarative 
> statements about what is required for the consumer to conform to its 
> role in the protocol. WS-RX is currently modeled to comply with the 
> latest version of WS-Policy: this draft does not allow declarative 
> statements around assertions that do not alter the wire level message, 
> ie, "observed" behavior of a service or so-called "informational 
> policies". While I think this severely retards what we can reasonably 
> achieve with Web services, I believe this is also a practical problem 
> for us: policies around the isolation levels of a service (as have 
> been proposed) clearly impact the decision to use a service rather 
> than the specifics of the wire message itself. It is not clear how 
> WS-Policy in its current form would regard a "No Support/Support" 
> assertion.
>
> For the acid transaction protocol(s), I don't believe we will have to 
> worry about intra-domain composition, but obviously we need to decide 
> this as a group based on what we think is necessary.
>
> This proposal does not discuss the binding of policies to specific 
> aspects of WSDL, eg, the operation, porttype, port and service level. 
> I see no reason to restrict this.

In general I'd like to stay clear of tying policies to WSDL. That looks 
too much like defining transactionality through inheritence (OTS 
1.0/1.1) and all of the disadvantages that that entails. Do we need to 
worry about where the policy assertions occur, or is that the domain of 
something else?

Mark.

-- 
Mark Little
Chief Architect
Arjuna Technologies Ltd
www.arjuna.com