WSD Requirements: add a requirement about safe and idempotent characteristics

The Web Services Description Requirements Working Draft dated 28
October 2002[1] is presented by the WSDWG as a last call for comments
until 31 December 2002.

I have reviewed the document, and would like to add a requirement for
the description language to specify if a service is safe or
idempotent. However, having not seen any other review within the
Working Group, I wanted to send this to www-ws-arch and maybe have the
WSAWG agree on sending this comment.

The characteristic of an operation to be safe is important on the Web,
e.g. for cacheability reasons. It is discussed in section 9.1.1 of the
HTTP/1.1 specification[3].

I think that it is important for services to be flagged as having
side-effects or not. One way to do so would be to simply have an
attribute that indicates whether an operation is safe or not.

Another way, which is more advanced and precise, would be to model the
interaction with a service using something similar to the Web Method
Specification Feature[2] as defined in SOAP 1.2.

I would therefore like to submit the following requirements to the
WSDWG:

	The description language MUST be able to indicate the
	characteristics of an operation as a Web interaction. The
	description of a service MUST indicate whether an operation is
	safe. A service SHOULD be exposed as a Web method, in a
	similar way as the Web Method Specification Feature[2].

Any comments?

I would like to try and get consensus on this by 17 December. I may
have to send this as a personnal comment if we cannot get to it by
then.

Regards,

Hugo

  1. http://www.w3.org/TR/2002/WD-ws-desc-reqs-20021028
  2. http://www.w3.org/TR/2002/WD-soap12-part2-20020626#WebMethodFeature
  3. http://www.ietf.org/rfc/rfc2616.txt
-- 
Hugo Haas - W3C
mailto:hugo@w3.org - http://www.w3.org/People/Hugo/

Received on Tuesday, 26 November 2002 12:58:00 UTC